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Composites news
ICOMPOSITES
lnews Looking into p i p i n g . . . Evaluation of the merits of using reinforcing fillers in thermoplastic pipes - such as pvc, polyethylene, polypropylene and abs - is the main aim of a proposed study to be undertaken by the Battelle Research Centre at Geneva. Financed by a group of industrial sponsors, the techno-economic survey is expected to give an indication as to the future cost performance and competitiveness of reinforced thermoplastics against other pipe materials. In spite of strong competition from such pipe materials as steel, cast iron, concrete, asbestos-cement and clay, thermoplastic pipes have met with considerable success over the past 10-12 years and, it is predicted, will continue to be used in increasing amounts as the market for piping grows. However, thermoplastic pipes currently depend on a raw material (oil) which is highly costsensitive and it is because of this that the Battelle survey has been proposed.
This road tanker is used to carry some 9 820 litres of beer finings. The tank, which has 3 separate compartments, is made with Celmar - British Celanese" polypropylene/glass fabric laminate. The material was chosen for its resistance to sulphur dioxide and for its ability to withstand hot water sterilization and de tergen t cleaning. British Celanese Ltd, Plastics Group Sales, PO Box 5, Spondon, Derby DE2 7BP, England.
The main aims of the study will be to provide information on: the most suitable fillers for a given thermoplastic pipe, and pretreatment needed for optimum effect; •
optimum filler content on a cost/performance basis; expected results of combining different filler materials (fibres with particulate fillers, for instance); the kind of thermoplastic pipes, and possibly classification (in terms of diameter/pressure constraints), most amenable to improvements.
It is hoped that the study will also serve as a guide for the selection of future research and development efforts, indicating the possible cost
66
advantages for different filler/thermoplastic pipe/application combinations.
Battelle Geneva Research Centre, 7 route de Drize, 1227 Carouge, Geneva, Switzerland
• . . all went well Some 5 km of grp pipes manufactured at the Poole factory of Redland Ltd and valued at £1.4 M - have been inspected by surveyors from Lloyd's Register Industrial Services before being shipped to Abu Dhabi in the Middle East. The pipes form a small but important part of a £300 M construction project which will provide Abu Dhabi with a complete sewerage network by 1981. Three sizes of pipe were manufactured in various diameters (1.9, 2.0 and 2.2 m), to facilitate shipping. Pipe lengths were mainly 10 m, although
some special lengths and bend sections were also made. Lloyd's Register surveyors reported to the consulting engineers on the workshop conditions and quality control procedures, and witnessed tests made by Redland Ltd on pipe test specimens. The lay-up of the glass fibre rovings and resin was also witnessed, as were hydraulic tests of all pipes. Final dimensional checks were made before the pipes were shipped to Abu Dhabi island.
Lloyd's Register of Shipping, 71 Fenchurch Street, London EC3M 4BS, England
Combined efforts Two companies in the North of England, with extensive experience in the separate disciplines of providing coated fabric architectural
COMPOSITES . APRIL 1978
COMPOSITES
news structures and the coated fabrics themselves, have recently formed a joint company to exploit their combined experience. The new company - called Fothergill & Harvey Structures L t d - will be jointly owned by Munton and Bryon Holdings Ltd (specialists in the construction and erection of fabric-covered structures) and Fothergill & Harvey Ltd (producers of glass fabric and ptfe-coated materials). Both roofs and complete buildings can be made from ptfe-coated glass fabric, which is itself made with woven glass yarn and ptfe containing glass microspheres (for reflecting sunlight). The woven fabrics (made with glass yarn having a smaller diameter than conventional glass filaments) are specially designed to impart extra flexibility - necessary in roof structure assembly. The ptfe-coated fabric meets current fire regulations and resists ageing, weathering and corrosive atmospheres and withstands ultra-violet radiation.
market. Called the Christine Pear, after the British coach who helped in the design and development work, the boat is constructed from a onepiece glass-reinforced laminate using RP 280 woven rovings from Fibreglass Ltd. The kit, which is produced by Reredos of Redditch, comes complete with internal structure in marine and aircraft plywood, aluminium saxboard, Perspex washboard and a fully equipped, double-action seat. It is hoped that the kit will enable an unskilled person to construct a competitive racing scull at a price about 50% less than a traditionally built boat.
Fibreglass Ltd, St Helens, Merseyside, WA 10 3TR, England
Covered-up to last
Make it yourself
Two year's exposure to the hot sunshine of Sicily and the combined efforts of salt-spray and sand erosion have provided a severe environment for grp panels surfaced with Du Pont's 'Tedlar' polyvinylflouride film. The panels - covering some 15 000 m 2 were installed on a greenhouse structure (Fig. 2) in 1975, replacing the pvc film previously used.
Simple tools and 16 hours work are all that are needed to construct a newlydesigned junior competition scull (Fig. 1) from a kit now on the British
In searching for a substitute for the pvc, which needed changing every 12 months, the owner of the greenhouse eventually chose grp surfaced with
Fothergill and Harvey Structures L td, Winsford, Cheshire, England
Fig. 1
Reducedcost and easeof construction are the main featuresof this grp single scull
COMPOSITES . APR I L 1978
Fig. 2 Some 15000m 2ofgrppanels, coated with polyester film, are used for this greenhouse in Sicily Tedlar. Although grp panels have many advantages (light weight, better insulation, impact resistance, etc) they presented two main disadvantages for the proposed use - yellowing of the polyester resin used, and erosion by wind and sand. These disadvantages were overcome by bonding a 25/~m layer of Tedtar onto the surface: the Tedlar thus provided the required resistance to erosion and prevented the degradation of the light transmission properties of the panels.
Du Pont (UK) Ltd, 18 Bream's Buildings, Fetter Lane, London EC4A IHT, England Fixed ratio m a c h i n e f o r resin i n j e c t i o n Accurate metering, mixing and dispensing of precatalysed and pre-accelerated resin mixtures is possible with the Twinflow F R F from Liquid Control Limited. The machine, which is a variant of the established Twinflow machine, is expected to be of interest to moulders in the grp industry where a maximum shot size of 300 cm 3 is adequate. Designed as a portable unit, the FRF has integral resin storage tanks and metering pumps; an optional feature is an integral electric mixing head which can be used as a replacement for the standard, static head. Two pumps are used to give a mixed fluid delivery of between
67
COMPOSITES
news 15 and 300 cm 3. Resin/catalyst ratios of between 1 : 1 and 20 : 1 can be dispensed, although the actual resin/ catalyst ratio may be higher depending upon the degree of doping of the preaccelerated resin mixture. When used with a 1 : 1 ratio, discharge rates of 3 litres/min can be achieved.
capacity have been made necessary by the continuing demand for the range of thermocomp materials throughout the USA and the rest of the world.
Liquid Control L td, 25 Harcourt Street, Kettering, Northants, England
Holding fast
Colours up to standards Rigid, flexible and reduced fire hazard type polyester gelcoats pigmented to selected British Standard colours are now available from BP Chemicals. In addition to the standard colours, special colour requirements can be met. The introduction of the new range of coloured gelcoats is offered in conjunction with the established, and extensive, Cellobond range of polyester resins. Colour cards showing pigment shades for the gelcoats are available from: BP Chemicals
Ltd, Stratton Street, London WlX 6LS, England; and from regional sales offices.
Keeping i t clean Up to 95% of the dust generated during cutting can be removed during operation of the Model 10K2775 Venturi vacuum saw, newly announced by ATA Engineering Processes (Fig. 3). The saw is air driven and the exhaust is used to suck the dust into an attached vacuum bag. A 101 mm diameter blade is fitted, capable of cutting grp laminates up to 12 mm thick and other materials up to 19 mm thick (according to material type). Although fitted with its own vacuum bag, the 10K2775 can be connected either remotely to the bag or to existing vacuum dust removal systems.
A TA Engineering Processes, A TA House, Ebbons Road, Hernel Hernpstead, Hertfordshire HP3 9QX, England
68
Fig. 3 Up to 95% dust extraction is possible with the Venturi vacuum saw
Making more Approval to proceed with the first phase of an expansion of the 'Delrin' acetal resin plant at Dordrecht in The Netherlands has been given by the works management of Du Pont de Nemours ((Nederlands) B.V. The engineering and design phase of the project is expected to take about 12 months, after which authorization of the construction phase will be considered. The planned expansion will increase capacity at the Dordrecht plant by nearly 40%.
Two extra-long Bighead Fasteners 63.5 mm and 76.2 mm - have been added to the six lengths (12.7, 19, 25.4, 31.8, 38 and 51 mm) already available off-the-shelf in the 6.35 mm diameter stud range of Bighead bonding and load-distributing products. These additions will, apart from other possible industrial uses, enable grp cladding and other panel materials to be firmly and easily secured to a wider range of, for example, timber studding (see Fig. 4). Furthermore, by using an extra nut as a distance adjuster on the shank of the Bighead Fastener, the grp panel can be made to stand off the studding so that, for example, thermal or acoustic glass fibre insulation materials can be placed in the gap so formed without materially affecting the strength of the anchorage in grp.
Bighead Bonding Fasteners Ltd, Unit 15, Elliott Road, West House Industrial Estate, Bournemouth, England
• . . and more Addition of processing equipment enabling production capacity of Thermocomp reinforced and/or lubricated thermoplastic compounds to be increased by 50% was announced at the end of last year by LNP Corporation. The expansion, which will take place at LNP's Santa Ana, California plant, follows an earlier 25% increase in production at the company's East coast plant in Thorndale, Pennsylvania. The enlargements in manufacturing
Fig. 4 Extra-long fastenerswill enable grp panelsto be connected to thicker timber studding
COMPOSITES. APRI L 1978
ICOMPOSITES
inews RP for projectors Prompted by the need for cost reduction, Bauer of West Germany have replaced die-cast metal with glass-reinforced Lexan (General Electric Plastics' polycarbonate resin), for the housings of domestic filmprojectors. The new housings are produced in only three mouldings (Fig. 5): the two main halves are in Lexan 3412 (20% glass-reinforced), and the side panel in Lexan 500 (10% glass-reinforced). Using only three mouldings has itself brought about cost-savings; assembly costs have also been reduced because metal inserts for fixing the interior parts are either fed automatically into the mould, or ultrasonically welded into the part after moulding. The two halves are secured using selftapping screws and the side panel is attached by snapfits.
General Electric Plastics BV, PB 117, Plasticslaan I, Bergen op Zoom, The Netherlands
The mixture works Difficulties encountered in handling and transporting steel fibre-reinforced shotcrete mixtures have been overcome in a system recently announced by the Tokyo-based Shimizu Construction Company. Extensive field tests using commercially available materials, admixtures and machines, were carried out by Shimizu, resulting in a hybrid system of two types of shotcrete machines, two types of cement, three types of steel fibre and four rates of mixing the fibres and cement. Factors such as concrete strength requirements, travelling distance (from mixing to construction sites) moisture and geological conditions at the work site, types of available mixing machine and properties of the sand, aggregate and cement are all analysed to enable a suitable combination to be chosen. Although steel fibre-reinforced shotcrete has been previously used in Japan, it has been limited to small-
COMPOSITES . APRI L 1978
Fig. 5 Usinginjection mouldedglass-reinforcedpolycarbonateresultsin cheaperprojector housings scale patching of existing concrete structures. However, in its most recent field test, Shimizu applied various formulae of the mix as a lining material for a 39.6 m tunnel. Thicknesses of between 300 and 510 mm were applied at a rate of some 600 mm/min: 2% by volume of steel fibres were used in a 1 : 1.28 : 2.8 cement: aggregate: sand mixture. It was found that the loss rate from dislodging and dropping of the fibre-reinforced shotcrete was some 10%, comparing well with the normal 50% loss with unreinforced shotcrete. Following the field trials, Shimuzi indicate that experience plays a significant role in successful applications of the material. Inevitable differences in cement, sand and aggregate all need to be evaluated to ensure optimum conditions for transportation and application.
French composite materials group French industry is becoming increasingly interested in composite materials of all sorts for replacing more traditional materials for already existing applications or for meeting
the requirements of the developing technologies. Most research on composites in France is done by industrial research teams working in isolation or in post graduate research centres of some of the 'grandes ~coles' (the elitest academic centres which are peculiar to France). In addition there is a great deal of interest by the smaller companies, without research teams, but an understandable reluctance to commit themselves to the material without more information. To help end the isolation of the French researchers and to facilitate the expansion of the use of composites in France it has been decided to form a working group which will hold conferences annually. It is hoped that not only will French research workers have the opportunity to meet each other and to exchange ideas but that those who want to use the material will also be able to get to know to whom they should turn. Further details of the Composite Materials Group can be obtained from Dr A.R. Bunsell, Ecole Nationale
Sup~rieures des Mines, Centre des Mat~riaux, BP No 87, 91003 EVR Y C~dex: details of the first conference are given in the 'Conferences, courses and exhibitions' section of Composites news.
69
COMPOSITES
news Publications
The following is a list of brief descriptions of books and literature that have recently been received. Full details can be obtained from the addressesas shown. Books for buying
Fatigue of filamentary composite materials and Flaw growth and fracture are two Special Technical Publications recently available from ASTM. Fatigue of filamentary composite materials is said to be particularly relevant to the problems of determining fatigue resoponse, characterizing fatigue data, predictions of fatigue response, the importance of special situations, and materials response in terms of design. Although some early work is reported, much of the book's contents is given to discussing new investigations and ideas - for example, new test methods. There is also a collection of data on the fatigue response of graphite/epoxy, boron/aluminium, boron/epoxy, S-glass/graphite/epoxy hybrids, and carbon fibre-reinforced polymethylmethacrylate composites, in a variety of laminate stacking sequences of importance to engineering applications. Flaw growth and fracture provides a review of the state-of-the-art efforts for both mechanical and analytical research in fracture mechanics. Current research described includes elastic/plastic behaviour, toughness characterisation of low-strength, high-toughness materials, environmental and residual-stress effects on crack initiation and propagation, and crack propagation under variableamplitude loading. Other topics discussed include fracture and fatigue behaviour for cracks in regions of
70
strain concentrations, and correlation between fracture mechanics data and data obtained from rapid, inexpensive tests. Fatigue of filamentary composite materials - STP 636 costs $;26.~0 (plus 3% shipping charges for USA, Canada and Mexico; 5% elsewhere); Flaw growth and fracture - STP 631 costs Pp49.75 (shipping charges as above); both books are available from ASTM, 1916 Race Street,
Philadelphia, PA 19103, USA. British rubber and plastics moulders is the title of a recent survey published by Jordan Dataquest, price £28. Essentially the survey presents a summary of the trading results of some 202 UK companies, based on the most up-to-date information available. Data quoted are turnover, exports, pre-tax profit, number of employees, salaries, current assets and liabilities, loan committments and net fixed assets. Figures for two consecutive years are given, so that some idea of continuing performance can be gained (although in no case are any figures quoted for performance after December 1976; and in some cases the last entry is for as early as December 1974). In addition to financial facts and figures, the report also gives a very brief outline of each company's products and services. It would seem, therefore, to be a good starting point for anyone intending to buy into the rubber and plastics industry; but of extremely limited technical interest.
British Standards Institution has recently published BS 2782, Part 10, Methods 1001-1005. BS 2782 deals with methods of testing plastics, and Part 10 specifically with testing of grp. The methods cover the following areas: Method 1001 (price £1.60) - Barcol hardness measurement; Method 1002 (price £1.60) - determination of loss on ignition; Method 1003 (price £2.20) - determination of tensile properties; Method 1004 (price £1.60) standard atmospheres for conditioning and testing; Method 1005 (price £1.60) - determination of flexural properties, three point method. Enquiries and orders should be sent to the Sales Department, BSI, 101
Pentonville Road, London N19ND, England. The Government reports announcements annual index - 1977 is scheduled for publication by NTIS in April of this year. The index is a single source reference to some 80 000 US Government-funded research projects and other source information embracing the entire field of science and technology. Bibliographic information on reports containing the results of research and development activity representing US Government investment of some ~20 000 M is presented. Agencies whose work is mentioned include NASA, EPA, ERDA, the National Bureau of Standards, the Atomic Energy Commission, National Science Foundation and the Department of Transportation. Reports are listed by subject, personal author, corporate author and accession/ report number.
Copies of the report, and details of other services offered, are available from Jordan Dataquest L td, Jordan
The Annual Index 1977 is produced as a six-volume set of about 7 000 pages and is available in the UK, price £305 (inclusive of air freight delivery from the US and surface delivery in the UK) from NTIS UK
House, 47 Brunswick Place, London N I 6EE, England.
Service Centre, PO Box 3, Alton, Hants GU34 2PG, England.
COMPOSITES. APR I L 1978
newsl
COMPOSITES
Books for free Ciba-Geigy's Bonded Structures Division has produced a new datasheet on the range of adhesives and structural materials manufactured by the Division. The range includes Redux adhesives, prepreg materials (glass, aramid and carbon fibres), honeycomb material for sandwich constructions, and fabricated honeycomb sandwich materials. Designed as a wall chart, the date-sheet can also be used in a standard A4 loose-leaf binder. Copies are available from the
Plastics Division, Ciba-Geigy Plastics and Additives Company, Duxford, Cambridge CB2 40A, UK
Standardised data sheets describing the main products and services available from the National Technical Information Service (NTIS) are now available from the UK Service Centre. NTIS products and services cover the whole field of science and technology, with the current list of over 100 000 reports, books and other documents being supplemented each month by up to 7 000 new titles. The new data sheets provide an insight to the scope of the NTIS operation - and the likely cost of making use of it.
NTIS UK Service Centre, PO Box 3, Alton, Hants GU34 2PG, England. TBA Industrial Products, Reinforced
Testing and test methods of fibre cement composites is the title of an international symposium to be held at the University of Sheffield on 5-7 April. In addition to the conference, there will be an associated exhibition of materials and equipment. The conference programme is to be divided into six main sessions, covering the following topics: rheology; quality control and fibre distribution, and non-destructive testing; strength tests; shrinkage and creep; durability and bonding; porosity and permeability. Thirty papers are to be formally presented with a further fifteen available for discussion. Dr F.A. Johnson, Industrial
Liaison Officer, Department of
COMPOSITES. APRI L 1978
the sheet also shows four examples of its successful use as a cladding material in four very different environments where hygiene is an important factor - a foodpreparation shop; a milk packaging plant; a poultry processing plant; and a solid state electronics 'clean air' laboratory. TBA
Industrial Products L td, Reinforced Plastics Division, PO Box 40, Rochdale, Lancs OL 12 7EQ, UK
Civil and Structural Engineering, University of Sheffield, Mappin Street, Sheffield S 1 3JD, England.
into sessions, covering the following topics: inorganic high modulus fibres; organic high modulus fibres; composite materials; composite materials in technology. There will also be a separate session for general discussion.
The Second Plastics Industries Exhibition is to be held at Belle Vue,
The Executive Secretary, Royal Society, 6 Carlton House Terrace, London, England.
Conferences, courses, exhibitions The following is a preview of some forthcoming events,arranged in chronological order. Further details can be obtained from the addressesgiven at the end of each item. A comprehensivelist of future meetings relating to composite materials can be found in the Calendarsection.
Plastics Division have produced a new, single data sheet on the use of Duraform (asbestos reinforced thermoplastic sheet material) in 'hygiene environments'. Giving brief, qualitative details of the performance of the material,
Enquiries should be directed to
Manchester on 17-21 April. This follows the successful debut of the exhibition in 1976. The scope of the exhibition is wide, covering all aspects of the plastics industry; and although originally planned as a UK-oriented event, considerable interest has been expressed by overseas companies and customers.
Mr Peter Rowe, Exhibitions for Industry Ltd, 157 Station Road East, Oxted, Surrey, England.
The Royal Society is to hold a Discussion Meeting on 18-19 May on the subject of New fibres and their composites. The meeting, which will take place at the Royal Society building in London, is to be divided
The Polymer Properties Group of the PRI is planning an international conference on Toughening of Plastics, to be held in London on 4-6 July. The aim of the meeting will be to review current knowledge relating to the industry -- including the chemistry of toughening; manufacture of toughened polymers; structure/ property relationships; rheology; melt processing and fabrication; and the economic outlook for toughened plastics. Full details and a conference programme can be obtained from:
Mrs Carol-Anne A/corn, The Plastics and Rubber Institute, 11 Hobart Place, London SWIW OHL, England.
71
newsl
ICOMPOSITES Keele University is to be the venue for the 3rd Conference on materials for use in medicine and biology, and for a symposium on bioceramics (on 13-15 and 16 September respectively). The meetings are being organized by the Biomaterials Group of the Biological Engineering Society, in association with the British Ceramics Society and the European Society for Biomaterials. The conference on mechanical properties of biomaterials will provide the opportunity for a review of the present knowledge about the mechanical aspects of human tissues and implant materials relevant to orthopaedics, cardiovascular surgery, neurosurgery, plastic and reconstructive surgery, and dentistry. The bioceramics symposium will also aim to review current knowledge, in the use of ceramic materials for medical purposes. The materials aspect of these problems, as it concerns properties, fabrication, metal/ceramic, adhesive/ ceramic and tissue/ceramic interfaces, and design, will receive particular attention. It is hoped that contributions will come both from research workers and industrial companies developing and manufacturing bioceramic materials and prostheses. Both meetings are expected to be of interest to a wide range of scientific disciplines, including mechanical and electronic engineering; physics; materials science (polymer science and technology, ceramics and metallurgy); and surgery. Details of the Biomaterials conference can be obtained from Dr G.W. Hastings,
72
Bio-Medical Engineering Unit, c/o Medical Institute, Hartshill, Stoke-onTrent, Staffordshire ST4 7NY, England; and of the Bioceramics symposium from Dr G.J. Gittens, Department of Ceramic Technology, North Staffordshire, College Road, Stoke-on-Trent, England.
Product development opportunities in paper/board and plastics combinations is the subject of an international conference being organised by Pira in conjunction with the British Paper and Board Industry Federation and the Plastics and Rubber Institute. The meeting will take place in London on 28-29 November. The purpose of the conference is to provide an opportunity for speakers from the paper, board, plastics and converting industries to present papers on various aspects of paper/board and plastics combinations. The emphasis of the meeting will be on new product concepts, techniques and equipment, and improvements to existing techniques or equipment. Full details of the scope of the conference programme can be obtained from: Ms Evelyn Pritchard, Information and Training Division, Pira, Randalls Road, Leatherhead, Surrey KT22 7RU, England.
The newly-formed Composite Materials Group in France is holding a meeting in Paris, on 19-20 September on Structure and Composite materials: behaviour, design and con trol. No
details of the conference programme have yet been made available, but those interested should contact Dr A.R. Bunsell, Eco/e Nationale Superieure des Mines de Paris, Centre des Materiaux, B.P. 87, 91003 Evry Cedex, France.
The 3rd international conference on plastics in medicine and surgery P/MS III is to be held on 21-22 June 1979, at Twente University of Technology, Enschede, Netherlands. This follows the successful previous meetings held in 1971 and 1975. It is hoped that the meeting will provide the opportunity for reviewing recent progress; to highlight advances made in the application of polymeric materials; and to discuss arising from the interface and interaction between materials (with an emphasis on the chemical/physical properties, and handling of those materials). The outline structure for the conference is expected to be as follows: blood compatability of materials and devices; toxicity of plastics and rubber; sterilization of materials and devices; tissue compatibility; materials applications in orthopaedics. Offers of papers under any of these headings (which are not exclusive of other relevant topics), are invited by the organisers. Intending authors are asked to submit a synopsis by 1 September of this year; final manuscripts will be required by 1 March 1979. Full details can be obtained from Mr J.N. Ratcliffe, PRI, 11 Hobart Place, London SWIW OHL, England.
COMPOSITES. APR I L 1978
lnews Looking into p i p i n g . . . Evaluation of the merits of using reinforcing fillers in thermoplastic pipes - such as pvc, polyethylene, polypropylene and abs - is the main aim of a proposed study to be undertaken by the Battelle Research Centre at Geneva. Financed by a group of industrial sponsors, the techno-economic survey is expected to give an indication as to the future cost performance and competitiveness of reinforced thermoplastics against other pipe materials. In spite of strong competition from such pipe materials as steel, cast iron, concrete, asbestos-cement and clay, thermoplastic pipes have met with considerable success over the past 10-12 years and, it is predicted, will continue to be used in increasing amounts as the market for piping grows. However, thermoplastic pipes currently depend on a raw material (oil) which is highly costsensitive and it is because of this that the Battelle survey has been proposed.
This road tanker is used to carry some 9 820 litres of beer finings. The tank, which has 3 separate compartments, is made with Celmar - British Celanese" polypropylene/glass fabric laminate. The material was chosen for its resistance to sulphur dioxide and for its ability to withstand hot water sterilization and de tergen t cleaning. British Celanese Ltd, Plastics Group Sales, PO Box 5, Spondon, Derby DE2 7BP, England.
The main aims of the study will be to provide information on: the most suitable fillers for a given thermoplastic pipe, and pretreatment needed for optimum effect; •
optimum filler content on a cost/performance basis; expected results of combining different filler materials (fibres with particulate fillers, for instance); the kind of thermoplastic pipes, and possibly classification (in terms of diameter/pressure constraints), most amenable to improvements.
It is hoped that the study will also serve as a guide for the selection of future research and development efforts, indicating the possible cost
66
advantages for different filler/thermoplastic pipe/application combinations.
Battelle Geneva Research Centre, 7 route de Drize, 1227 Carouge, Geneva, Switzerland
• . . all went well Some 5 km of grp pipes manufactured at the Poole factory of Redland Ltd and valued at £1.4 M - have been inspected by surveyors from Lloyd's Register Industrial Services before being shipped to Abu Dhabi in the Middle East. The pipes form a small but important part of a £300 M construction project which will provide Abu Dhabi with a complete sewerage network by 1981. Three sizes of pipe were manufactured in various diameters (1.9, 2.0 and 2.2 m), to facilitate shipping. Pipe lengths were mainly 10 m, although
some special lengths and bend sections were also made. Lloyd's Register surveyors reported to the consulting engineers on the workshop conditions and quality control procedures, and witnessed tests made by Redland Ltd on pipe test specimens. The lay-up of the glass fibre rovings and resin was also witnessed, as were hydraulic tests of all pipes. Final dimensional checks were made before the pipes were shipped to Abu Dhabi island.
Lloyd's Register of Shipping, 71 Fenchurch Street, London EC3M 4BS, England
Combined efforts Two companies in the North of England, with extensive experience in the separate disciplines of providing coated fabric architectural
COMPOSITES . APRIL 1978
COMPOSITES
news structures and the coated fabrics themselves, have recently formed a joint company to exploit their combined experience. The new company - called Fothergill & Harvey Structures L t d - will be jointly owned by Munton and Bryon Holdings Ltd (specialists in the construction and erection of fabric-covered structures) and Fothergill & Harvey Ltd (producers of glass fabric and ptfe-coated materials). Both roofs and complete buildings can be made from ptfe-coated glass fabric, which is itself made with woven glass yarn and ptfe containing glass microspheres (for reflecting sunlight). The woven fabrics (made with glass yarn having a smaller diameter than conventional glass filaments) are specially designed to impart extra flexibility - necessary in roof structure assembly. The ptfe-coated fabric meets current fire regulations and resists ageing, weathering and corrosive atmospheres and withstands ultra-violet radiation.
market. Called the Christine Pear, after the British coach who helped in the design and development work, the boat is constructed from a onepiece glass-reinforced laminate using RP 280 woven rovings from Fibreglass Ltd. The kit, which is produced by Reredos of Redditch, comes complete with internal structure in marine and aircraft plywood, aluminium saxboard, Perspex washboard and a fully equipped, double-action seat. It is hoped that the kit will enable an unskilled person to construct a competitive racing scull at a price about 50% less than a traditionally built boat.
Fibreglass Ltd, St Helens, Merseyside, WA 10 3TR, England
Covered-up to last
Make it yourself
Two year's exposure to the hot sunshine of Sicily and the combined efforts of salt-spray and sand erosion have provided a severe environment for grp panels surfaced with Du Pont's 'Tedlar' polyvinylflouride film. The panels - covering some 15 000 m 2 were installed on a greenhouse structure (Fig. 2) in 1975, replacing the pvc film previously used.
Simple tools and 16 hours work are all that are needed to construct a newlydesigned junior competition scull (Fig. 1) from a kit now on the British
In searching for a substitute for the pvc, which needed changing every 12 months, the owner of the greenhouse eventually chose grp surfaced with
Fothergill and Harvey Structures L td, Winsford, Cheshire, England
Fig. 1
Reducedcost and easeof construction are the main featuresof this grp single scull
COMPOSITES . APR I L 1978
Fig. 2 Some 15000m 2ofgrppanels, coated with polyester film, are used for this greenhouse in Sicily Tedlar. Although grp panels have many advantages (light weight, better insulation, impact resistance, etc) they presented two main disadvantages for the proposed use - yellowing of the polyester resin used, and erosion by wind and sand. These disadvantages were overcome by bonding a 25/~m layer of Tedtar onto the surface: the Tedlar thus provided the required resistance to erosion and prevented the degradation of the light transmission properties of the panels.
Du Pont (UK) Ltd, 18 Bream's Buildings, Fetter Lane, London EC4A IHT, England Fixed ratio m a c h i n e f o r resin i n j e c t i o n Accurate metering, mixing and dispensing of precatalysed and pre-accelerated resin mixtures is possible with the Twinflow F R F from Liquid Control Limited. The machine, which is a variant of the established Twinflow machine, is expected to be of interest to moulders in the grp industry where a maximum shot size of 300 cm 3 is adequate. Designed as a portable unit, the FRF has integral resin storage tanks and metering pumps; an optional feature is an integral electric mixing head which can be used as a replacement for the standard, static head. Two pumps are used to give a mixed fluid delivery of between
67
COMPOSITES
news 15 and 300 cm 3. Resin/catalyst ratios of between 1 : 1 and 20 : 1 can be dispensed, although the actual resin/ catalyst ratio may be higher depending upon the degree of doping of the preaccelerated resin mixture. When used with a 1 : 1 ratio, discharge rates of 3 litres/min can be achieved.
capacity have been made necessary by the continuing demand for the range of thermocomp materials throughout the USA and the rest of the world.
Liquid Control L td, 25 Harcourt Street, Kettering, Northants, England
Holding fast
Colours up to standards Rigid, flexible and reduced fire hazard type polyester gelcoats pigmented to selected British Standard colours are now available from BP Chemicals. In addition to the standard colours, special colour requirements can be met. The introduction of the new range of coloured gelcoats is offered in conjunction with the established, and extensive, Cellobond range of polyester resins. Colour cards showing pigment shades for the gelcoats are available from: BP Chemicals
Ltd, Stratton Street, London WlX 6LS, England; and from regional sales offices.
Keeping i t clean Up to 95% of the dust generated during cutting can be removed during operation of the Model 10K2775 Venturi vacuum saw, newly announced by ATA Engineering Processes (Fig. 3). The saw is air driven and the exhaust is used to suck the dust into an attached vacuum bag. A 101 mm diameter blade is fitted, capable of cutting grp laminates up to 12 mm thick and other materials up to 19 mm thick (according to material type). Although fitted with its own vacuum bag, the 10K2775 can be connected either remotely to the bag or to existing vacuum dust removal systems.
A TA Engineering Processes, A TA House, Ebbons Road, Hernel Hernpstead, Hertfordshire HP3 9QX, England
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Fig. 3 Up to 95% dust extraction is possible with the Venturi vacuum saw
Making more Approval to proceed with the first phase of an expansion of the 'Delrin' acetal resin plant at Dordrecht in The Netherlands has been given by the works management of Du Pont de Nemours ((Nederlands) B.V. The engineering and design phase of the project is expected to take about 12 months, after which authorization of the construction phase will be considered. The planned expansion will increase capacity at the Dordrecht plant by nearly 40%.
Two extra-long Bighead Fasteners 63.5 mm and 76.2 mm - have been added to the six lengths (12.7, 19, 25.4, 31.8, 38 and 51 mm) already available off-the-shelf in the 6.35 mm diameter stud range of Bighead bonding and load-distributing products. These additions will, apart from other possible industrial uses, enable grp cladding and other panel materials to be firmly and easily secured to a wider range of, for example, timber studding (see Fig. 4). Furthermore, by using an extra nut as a distance adjuster on the shank of the Bighead Fastener, the grp panel can be made to stand off the studding so that, for example, thermal or acoustic glass fibre insulation materials can be placed in the gap so formed without materially affecting the strength of the anchorage in grp.
Bighead Bonding Fasteners Ltd, Unit 15, Elliott Road, West House Industrial Estate, Bournemouth, England
• . . and more Addition of processing equipment enabling production capacity of Thermocomp reinforced and/or lubricated thermoplastic compounds to be increased by 50% was announced at the end of last year by LNP Corporation. The expansion, which will take place at LNP's Santa Ana, California plant, follows an earlier 25% increase in production at the company's East coast plant in Thorndale, Pennsylvania. The enlargements in manufacturing
Fig. 4 Extra-long fastenerswill enable grp panelsto be connected to thicker timber studding
COMPOSITES. APRI L 1978
ICOMPOSITES
inews RP for projectors Prompted by the need for cost reduction, Bauer of West Germany have replaced die-cast metal with glass-reinforced Lexan (General Electric Plastics' polycarbonate resin), for the housings of domestic filmprojectors. The new housings are produced in only three mouldings (Fig. 5): the two main halves are in Lexan 3412 (20% glass-reinforced), and the side panel in Lexan 500 (10% glass-reinforced). Using only three mouldings has itself brought about cost-savings; assembly costs have also been reduced because metal inserts for fixing the interior parts are either fed automatically into the mould, or ultrasonically welded into the part after moulding. The two halves are secured using selftapping screws and the side panel is attached by snapfits.
General Electric Plastics BV, PB 117, Plasticslaan I, Bergen op Zoom, The Netherlands
The mixture works Difficulties encountered in handling and transporting steel fibre-reinforced shotcrete mixtures have been overcome in a system recently announced by the Tokyo-based Shimizu Construction Company. Extensive field tests using commercially available materials, admixtures and machines, were carried out by Shimizu, resulting in a hybrid system of two types of shotcrete machines, two types of cement, three types of steel fibre and four rates of mixing the fibres and cement. Factors such as concrete strength requirements, travelling distance (from mixing to construction sites) moisture and geological conditions at the work site, types of available mixing machine and properties of the sand, aggregate and cement are all analysed to enable a suitable combination to be chosen. Although steel fibre-reinforced shotcrete has been previously used in Japan, it has been limited to small-
COMPOSITES . APRI L 1978
Fig. 5 Usinginjection mouldedglass-reinforcedpolycarbonateresultsin cheaperprojector housings scale patching of existing concrete structures. However, in its most recent field test, Shimizu applied various formulae of the mix as a lining material for a 39.6 m tunnel. Thicknesses of between 300 and 510 mm were applied at a rate of some 600 mm/min: 2% by volume of steel fibres were used in a 1 : 1.28 : 2.8 cement: aggregate: sand mixture. It was found that the loss rate from dislodging and dropping of the fibre-reinforced shotcrete was some 10%, comparing well with the normal 50% loss with unreinforced shotcrete. Following the field trials, Shimuzi indicate that experience plays a significant role in successful applications of the material. Inevitable differences in cement, sand and aggregate all need to be evaluated to ensure optimum conditions for transportation and application.
French composite materials group French industry is becoming increasingly interested in composite materials of all sorts for replacing more traditional materials for already existing applications or for meeting
the requirements of the developing technologies. Most research on composites in France is done by industrial research teams working in isolation or in post graduate research centres of some of the 'grandes ~coles' (the elitest academic centres which are peculiar to France). In addition there is a great deal of interest by the smaller companies, without research teams, but an understandable reluctance to commit themselves to the material without more information. To help end the isolation of the French researchers and to facilitate the expansion of the use of composites in France it has been decided to form a working group which will hold conferences annually. It is hoped that not only will French research workers have the opportunity to meet each other and to exchange ideas but that those who want to use the material will also be able to get to know to whom they should turn. Further details of the Composite Materials Group can be obtained from Dr A.R. Bunsell, Ecole Nationale
Sup~rieures des Mines, Centre des Mat~riaux, BP No 87, 91003 EVR Y C~dex: details of the first conference are given in the 'Conferences, courses and exhibitions' section of Composites news.
69
COMPOSITES
news Publications
The following is a list of brief descriptions of books and literature that have recently been received. Full details can be obtained from the addressesas shown. Books for buying
Fatigue of filamentary composite materials and Flaw growth and fracture are two Special Technical Publications recently available from ASTM. Fatigue of filamentary composite materials is said to be particularly relevant to the problems of determining fatigue resoponse, characterizing fatigue data, predictions of fatigue response, the importance of special situations, and materials response in terms of design. Although some early work is reported, much of the book's contents is given to discussing new investigations and ideas - for example, new test methods. There is also a collection of data on the fatigue response of graphite/epoxy, boron/aluminium, boron/epoxy, S-glass/graphite/epoxy hybrids, and carbon fibre-reinforced polymethylmethacrylate composites, in a variety of laminate stacking sequences of importance to engineering applications. Flaw growth and fracture provides a review of the state-of-the-art efforts for both mechanical and analytical research in fracture mechanics. Current research described includes elastic/plastic behaviour, toughness characterisation of low-strength, high-toughness materials, environmental and residual-stress effects on crack initiation and propagation, and crack propagation under variableamplitude loading. Other topics discussed include fracture and fatigue behaviour for cracks in regions of
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strain concentrations, and correlation between fracture mechanics data and data obtained from rapid, inexpensive tests. Fatigue of filamentary composite materials - STP 636 costs $;26.~0 (plus 3% shipping charges for USA, Canada and Mexico; 5% elsewhere); Flaw growth and fracture - STP 631 costs Pp49.75 (shipping charges as above); both books are available from ASTM, 1916 Race Street,
Philadelphia, PA 19103, USA. British rubber and plastics moulders is the title of a recent survey published by Jordan Dataquest, price £28. Essentially the survey presents a summary of the trading results of some 202 UK companies, based on the most up-to-date information available. Data quoted are turnover, exports, pre-tax profit, number of employees, salaries, current assets and liabilities, loan committments and net fixed assets. Figures for two consecutive years are given, so that some idea of continuing performance can be gained (although in no case are any figures quoted for performance after December 1976; and in some cases the last entry is for as early as December 1974). In addition to financial facts and figures, the report also gives a very brief outline of each company's products and services. It would seem, therefore, to be a good starting point for anyone intending to buy into the rubber and plastics industry; but of extremely limited technical interest.
British Standards Institution has recently published BS 2782, Part 10, Methods 1001-1005. BS 2782 deals with methods of testing plastics, and Part 10 specifically with testing of grp. The methods cover the following areas: Method 1001 (price £1.60) - Barcol hardness measurement; Method 1002 (price £1.60) - determination of loss on ignition; Method 1003 (price £2.20) - determination of tensile properties; Method 1004 (price £1.60) standard atmospheres for conditioning and testing; Method 1005 (price £1.60) - determination of flexural properties, three point method. Enquiries and orders should be sent to the Sales Department, BSI, 101
Pentonville Road, London N19ND, England. The Government reports announcements annual index - 1977 is scheduled for publication by NTIS in April of this year. The index is a single source reference to some 80 000 US Government-funded research projects and other source information embracing the entire field of science and technology. Bibliographic information on reports containing the results of research and development activity representing US Government investment of some ~20 000 M is presented. Agencies whose work is mentioned include NASA, EPA, ERDA, the National Bureau of Standards, the Atomic Energy Commission, National Science Foundation and the Department of Transportation. Reports are listed by subject, personal author, corporate author and accession/ report number.
Copies of the report, and details of other services offered, are available from Jordan Dataquest L td, Jordan
The Annual Index 1977 is produced as a six-volume set of about 7 000 pages and is available in the UK, price £305 (inclusive of air freight delivery from the US and surface delivery in the UK) from NTIS UK
House, 47 Brunswick Place, London N I 6EE, England.
Service Centre, PO Box 3, Alton, Hants GU34 2PG, England.
COMPOSITES. APR I L 1978
newsl
COMPOSITES
Books for free Ciba-Geigy's Bonded Structures Division has produced a new datasheet on the range of adhesives and structural materials manufactured by the Division. The range includes Redux adhesives, prepreg materials (glass, aramid and carbon fibres), honeycomb material for sandwich constructions, and fabricated honeycomb sandwich materials. Designed as a wall chart, the date-sheet can also be used in a standard A4 loose-leaf binder. Copies are available from the
Plastics Division, Ciba-Geigy Plastics and Additives Company, Duxford, Cambridge CB2 40A, UK
Standardised data sheets describing the main products and services available from the National Technical Information Service (NTIS) are now available from the UK Service Centre. NTIS products and services cover the whole field of science and technology, with the current list of over 100 000 reports, books and other documents being supplemented each month by up to 7 000 new titles. The new data sheets provide an insight to the scope of the NTIS operation - and the likely cost of making use of it.
NTIS UK Service Centre, PO Box 3, Alton, Hants GU34 2PG, England. TBA Industrial Products, Reinforced
Testing and test methods of fibre cement composites is the title of an international symposium to be held at the University of Sheffield on 5-7 April. In addition to the conference, there will be an associated exhibition of materials and equipment. The conference programme is to be divided into six main sessions, covering the following topics: rheology; quality control and fibre distribution, and non-destructive testing; strength tests; shrinkage and creep; durability and bonding; porosity and permeability. Thirty papers are to be formally presented with a further fifteen available for discussion. Dr F.A. Johnson, Industrial
Liaison Officer, Department of
COMPOSITES. APRI L 1978
the sheet also shows four examples of its successful use as a cladding material in four very different environments where hygiene is an important factor - a foodpreparation shop; a milk packaging plant; a poultry processing plant; and a solid state electronics 'clean air' laboratory. TBA
Industrial Products L td, Reinforced Plastics Division, PO Box 40, Rochdale, Lancs OL 12 7EQ, UK
Civil and Structural Engineering, University of Sheffield, Mappin Street, Sheffield S 1 3JD, England.
into sessions, covering the following topics: inorganic high modulus fibres; organic high modulus fibres; composite materials; composite materials in technology. There will also be a separate session for general discussion.
The Second Plastics Industries Exhibition is to be held at Belle Vue,
The Executive Secretary, Royal Society, 6 Carlton House Terrace, London, England.
Conferences, courses, exhibitions The following is a preview of some forthcoming events,arranged in chronological order. Further details can be obtained from the addressesgiven at the end of each item. A comprehensivelist of future meetings relating to composite materials can be found in the Calendarsection.
Plastics Division have produced a new, single data sheet on the use of Duraform (asbestos reinforced thermoplastic sheet material) in 'hygiene environments'. Giving brief, qualitative details of the performance of the material,
Enquiries should be directed to
Manchester on 17-21 April. This follows the successful debut of the exhibition in 1976. The scope of the exhibition is wide, covering all aspects of the plastics industry; and although originally planned as a UK-oriented event, considerable interest has been expressed by overseas companies and customers.
Mr Peter Rowe, Exhibitions for Industry Ltd, 157 Station Road East, Oxted, Surrey, England.
The Royal Society is to hold a Discussion Meeting on 18-19 May on the subject of New fibres and their composites. The meeting, which will take place at the Royal Society building in London, is to be divided
The Polymer Properties Group of the PRI is planning an international conference on Toughening of Plastics, to be held in London on 4-6 July. The aim of the meeting will be to review current knowledge relating to the industry -- including the chemistry of toughening; manufacture of toughened polymers; structure/ property relationships; rheology; melt processing and fabrication; and the economic outlook for toughened plastics. Full details and a conference programme can be obtained from:
Mrs Carol-Anne A/corn, The Plastics and Rubber Institute, 11 Hobart Place, London SWIW OHL, England.
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newsl
ICOMPOSITES Keele University is to be the venue for the 3rd Conference on materials for use in medicine and biology, and for a symposium on bioceramics (on 13-15 and 16 September respectively). The meetings are being organized by the Biomaterials Group of the Biological Engineering Society, in association with the British Ceramics Society and the European Society for Biomaterials. The conference on mechanical properties of biomaterials will provide the opportunity for a review of the present knowledge about the mechanical aspects of human tissues and implant materials relevant to orthopaedics, cardiovascular surgery, neurosurgery, plastic and reconstructive surgery, and dentistry. The bioceramics symposium will also aim to review current knowledge, in the use of ceramic materials for medical purposes. The materials aspect of these problems, as it concerns properties, fabrication, metal/ceramic, adhesive/ ceramic and tissue/ceramic interfaces, and design, will receive particular attention. It is hoped that contributions will come both from research workers and industrial companies developing and manufacturing bioceramic materials and prostheses. Both meetings are expected to be of interest to a wide range of scientific disciplines, including mechanical and electronic engineering; physics; materials science (polymer science and technology, ceramics and metallurgy); and surgery. Details of the Biomaterials conference can be obtained from Dr G.W. Hastings,
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Bio-Medical Engineering Unit, c/o Medical Institute, Hartshill, Stoke-onTrent, Staffordshire ST4 7NY, England; and of the Bioceramics symposium from Dr G.J. Gittens, Department of Ceramic Technology, North Staffordshire, College Road, Stoke-on-Trent, England.
Product development opportunities in paper/board and plastics combinations is the subject of an international conference being organised by Pira in conjunction with the British Paper and Board Industry Federation and the Plastics and Rubber Institute. The meeting will take place in London on 28-29 November. The purpose of the conference is to provide an opportunity for speakers from the paper, board, plastics and converting industries to present papers on various aspects of paper/board and plastics combinations. The emphasis of the meeting will be on new product concepts, techniques and equipment, and improvements to existing techniques or equipment. Full details of the scope of the conference programme can be obtained from: Ms Evelyn Pritchard, Information and Training Division, Pira, Randalls Road, Leatherhead, Surrey KT22 7RU, England.
The newly-formed Composite Materials Group in France is holding a meeting in Paris, on 19-20 September on Structure and Composite materials: behaviour, design and con trol. No
details of the conference programme have yet been made available, but those interested should contact Dr A.R. Bunsell, Eco/e Nationale Superieure des Mines de Paris, Centre des Materiaux, B.P. 87, 91003 Evry Cedex, France.
The 3rd international conference on plastics in medicine and surgery P/MS III is to be held on 21-22 June 1979, at Twente University of Technology, Enschede, Netherlands. This follows the successful previous meetings held in 1971 and 1975. It is hoped that the meeting will provide the opportunity for reviewing recent progress; to highlight advances made in the application of polymeric materials; and to discuss arising from the interface and interaction between materials (with an emphasis on the chemical/physical properties, and handling of those materials). The outline structure for the conference is expected to be as follows: blood compatability of materials and devices; toxicity of plastics and rubber; sterilization of materials and devices; tissue compatibility; materials applications in orthopaedics. Offers of papers under any of these headings (which are not exclusive of other relevant topics), are invited by the organisers. Intending authors are asked to submit a synopsis by 1 September of this year; final manuscripts will be required by 1 March 1979. Full details can be obtained from Mr J.N. Ratcliffe, PRI, 11 Hobart Place, London SWIW OHL, England.
COMPOSITES. APR I L 1978