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998. Progress of the remelting technique for steels in vacuum arc furnaces
Classified abstracts 990--999 tice has produced steels of very low oxygen content and gives a much more satisfactory inclusion distribution pattern than the standard double slag vacuum degassing practice. In addition work being carried out to determine the effect of vacuum degassing on the elevated temperature properties of a 1 per cent Cr, 0.5 per cent Mo steel is outlined. The results obtained so far indicate that vacuum degassing has little or no effect on the creep, proof stress and stress rupture properties. Three tables, five diagrams and nine references. (Great
workability due to lower level of oxide type inclusions, are reviewed together with operational benefits such as the improvements associated with the controlled addition facilities. Twelve diagrams.
(Great Britain) I K Maclean and 3 M Lupton, Special Report No 92, Iron and Steel
Institute, London, November 1965, ( in press) .
37 : 53 990. The future of vacuum degassing. (Great Britain} The paper summarizes progress in the various vacuum steel degassing processes and their application over the past decade and suggests some new lines of development which are likely to receive attention. Greatly increased use of vacuum treatment is envisaged not only for removal of hydrogen and oxygen but also nitrogen and volatiles. More economical and complete control of alloying in the steel making process is also foreseen. (Great Britain) Anon, Special Report No 92, lron and Steel Institute, London,
37 : 53 995. Vacuum treatment of special steels. (Great Britain) The paper is primarily concerned with the application of the D o r t m u n d Horden Huttenunion process at English Steel Corporation. Hydrogen removal is discussed. The conditions for oxygen removal, its effect upon cleanness, and the effects of conventional deoxidation practices under vacuum are discussed at some length. The advantages of having an associated alloying system with the degassing process are demonstrated. Certain modifications to steelmaking practice that are made possible as a result of degassing and alloying are described. The possible effect of degassing upon ingot surface quality, and the effect of degassing stainless steels, are discussed very briefly, there being at the moment too little information to draw positive conclusions. Two tables and 10 diagrams. J C C Leach and W Sorby, Special Report No 92, Iron and Steel
November 1965, (inpress).
Institute, London, November 1965, ( in press).
Britain) K Knaggs and P H Bruxham, Special Report Iron and Steel Institute, London, November 1965, (in press).
37 : 53 991. Vacuum degassing of carbon and alloy forging steels.
(Great
37 : 47 996. A new instrument for determination of gas content in metals.
Britain)
(USA}
Results are given of the hydrogen contents obtained on vacuum degassed carbon and low alloy steels at William Beardmore and Company and Firth Brown using ladle vacuum degassing techniques. Details are also given of the consequent reductions in heat treatment cycles, the internal quality and mechanical properties for forgings. Steelmaking practice for vacuum degassing casts is described. It has been found that a shortened refining time can be used for certain carbon steel forgings, and this work is being further pursued. Significant improvements in the cleanness of some steel qualities have also been made by modifications to normal furnace practice to integrate this with the vacuum degassing operation. In particular, En. 31 billet and carbon chrome hardened steel rolls can now be produced with a very low incidence of major inclusions. A production improvement in quality is also reported for vacuum degassed F.V. 448 steel for aircraft discs. Four tables, 10 figures. (Great
The instrument described in this paper consists of an all-metal vacuum fusion apparatus assembled as a unit. The items mentioned include a resistance-heated graphite tube furnace for melting the sample, vacuum-pumping system, infra-red analyser, thermal conductivity analyser, pyrometer, gauges, and a strip chart recorder. The sample under investigation is dropped through an interlock into a carbon-enriched premelt contained in the furnace, the liberated gas being removed by the diffusion pump and then compressed by a collector pump into a chamber of known volume. With the aid of standard calibration curves the proportion of oxygen, hydrogen and nitrogen in the collected gas mixture can be determined directly from the recorded quantity. Some typical results are presented. G Ramsey, O Winkler and T Kraus, Trans Vac Metall Conference,
1964, Amer Vac Soc, Boston, Mass, (1965) , pp 421-431.
37 : 53 992. Vacuum degassing of high alloy steels: Part 1. (Great Britain) The operation of the continuous vacuum steel degassing unit developed at BISRA and installed at the Low Moore Alloy Steel Works is described., Some operational data and the effect of vacuum treatment on the composition of a total of 30 casts is shown for En. 52, 56D, 57, 58, 59, a high chrome tool steel and a Cr. MoV alloy. Two tables and four diagrams. (Great Britain) G Hoyle and M A Ramsbuttom, Special Report No 92, Iron and Steel
37 997. Application of vacuum metallurgical processes to the manufacture of uranium carbide fuels. (USA) Various manufacturing processses for the production of uranium monocarbide fuel elements are described and compared, the treated material to have certain specified properties including close limits for the carbon content. The methods evaluated included vacuum induction casting, consumable electrode skull casting, a vacuum carbon-arc skull casting process, an electron beam skull casting process, and a melt stock manufacturing process based on the carbothermic reduction of UO~ utilizing a vacuum induction furnace. The relative merits of the different processes are discussed in detail. D H Turner, Trans Vac Metall Conference, 1964, Amer Vnc Soc,
Institute, London, November 1965, (in press}.
Boston, Mass, (1965), pp 306-315.
Britain) A G MeMillan et al, Special Report No 92, Iron and Steel Institute,
London, November 1965, (in press).
37 : 53 993. Vacuum degassiug of high alloy steels: Part 2. (Great Britain) This paper describes some practical aspects together with technical and commercial advantages of steel-making practice as applied to the BISRA continuous degassing plant. They also discuss in detail the defects in En. 52 and 59 valve steel which vacuum treatment eliminates together with the associated test procedures. Two tables, eight diagrams. (Great Britain) D Hall et al, Special Report No 92, Iron and Steel Institute, London,
November 1965, (in press}. 37 : 53 994. Some aspects of the vacuum treatment of bulk steels for the wire drawing industry. (Great Britain) A consideration of the demands of the wire drawing industry with respect to the quality of the company's products and the need for replacing some of the grades with low alloy materials led to proposals being made in 1961 that the facilities of one of the steel plants at the Irlam Works of LSCM be extended by the addition of a 120ton D o r t m u n d Hoerder type vacuum degassing unit at Lancashire Steel Manufacturing Company. Finally some of the technical benefits, such as improved cold
37 : 41 998. Progress of the remelting technique for steels in vacuum are furnaces. (USA) Improvements in the control of the arc length and in the manner in which electrodes are prepared have contributed to a uniform remelting process which results in fewer inhomogeneities in the ingot. By controlling the arc and the molten pool, it is possible to obtain freckle-free ingots of high-strength steel. Ingots of high-speed steel with a uniform as-cast structure and small carbide grains can be produced by a modified remelting technique. The electron beam furnace offers further possibilities for the improvement of mechanical properties of special steels. The temper embrittlement of a highstrength steel can be eliminated by a slow remelting. Also, the fatigue properties can be improved by similar procedures. (Author) I Sperner, Trans Vac Metall Conference, 1964, Amer Vac Soc,
Boston, Mass, (1965), pp 354-365. 37:47 999. Some factors affecting (steel) degassing by the R-H circulating flow process. (USA) The equipment described in this paper consists essentially of an evacuated chamber provided with two pipe-leg extensions which are
613
workability due to lower level of oxide type inclusions, are reviewed together with operational benefits such as the improvements associated with the controlled addition facilities. Twelve diagrams.
(Great Britain) I K Maclean and 3 M Lupton, Special Report No 92, Iron and Steel
Institute, London, November 1965, ( in press) .
37 : 53 990. The future of vacuum degassing. (Great Britain} The paper summarizes progress in the various vacuum steel degassing processes and their application over the past decade and suggests some new lines of development which are likely to receive attention. Greatly increased use of vacuum treatment is envisaged not only for removal of hydrogen and oxygen but also nitrogen and volatiles. More economical and complete control of alloying in the steel making process is also foreseen. (Great Britain) Anon, Special Report No 92, lron and Steel Institute, London,
37 : 53 995. Vacuum treatment of special steels. (Great Britain) The paper is primarily concerned with the application of the D o r t m u n d Horden Huttenunion process at English Steel Corporation. Hydrogen removal is discussed. The conditions for oxygen removal, its effect upon cleanness, and the effects of conventional deoxidation practices under vacuum are discussed at some length. The advantages of having an associated alloying system with the degassing process are demonstrated. Certain modifications to steelmaking practice that are made possible as a result of degassing and alloying are described. The possible effect of degassing upon ingot surface quality, and the effect of degassing stainless steels, are discussed very briefly, there being at the moment too little information to draw positive conclusions. Two tables and 10 diagrams. J C C Leach and W Sorby, Special Report No 92, Iron and Steel
November 1965, (inpress).
Institute, London, November 1965, ( in press).
Britain) K Knaggs and P H Bruxham, Special Report Iron and Steel Institute, London, November 1965, (in press).
37 : 53 991. Vacuum degassing of carbon and alloy forging steels.
(Great
37 : 47 996. A new instrument for determination of gas content in metals.
Britain)
(USA}
Results are given of the hydrogen contents obtained on vacuum degassed carbon and low alloy steels at William Beardmore and Company and Firth Brown using ladle vacuum degassing techniques. Details are also given of the consequent reductions in heat treatment cycles, the internal quality and mechanical properties for forgings. Steelmaking practice for vacuum degassing casts is described. It has been found that a shortened refining time can be used for certain carbon steel forgings, and this work is being further pursued. Significant improvements in the cleanness of some steel qualities have also been made by modifications to normal furnace practice to integrate this with the vacuum degassing operation. In particular, En. 31 billet and carbon chrome hardened steel rolls can now be produced with a very low incidence of major inclusions. A production improvement in quality is also reported for vacuum degassed F.V. 448 steel for aircraft discs. Four tables, 10 figures. (Great
The instrument described in this paper consists of an all-metal vacuum fusion apparatus assembled as a unit. The items mentioned include a resistance-heated graphite tube furnace for melting the sample, vacuum-pumping system, infra-red analyser, thermal conductivity analyser, pyrometer, gauges, and a strip chart recorder. The sample under investigation is dropped through an interlock into a carbon-enriched premelt contained in the furnace, the liberated gas being removed by the diffusion pump and then compressed by a collector pump into a chamber of known volume. With the aid of standard calibration curves the proportion of oxygen, hydrogen and nitrogen in the collected gas mixture can be determined directly from the recorded quantity. Some typical results are presented. G Ramsey, O Winkler and T Kraus, Trans Vac Metall Conference,
1964, Amer Vac Soc, Boston, Mass, (1965) , pp 421-431.
37 : 53 992. Vacuum degassing of high alloy steels: Part 1. (Great Britain) The operation of the continuous vacuum steel degassing unit developed at BISRA and installed at the Low Moore Alloy Steel Works is described., Some operational data and the effect of vacuum treatment on the composition of a total of 30 casts is shown for En. 52, 56D, 57, 58, 59, a high chrome tool steel and a Cr. MoV alloy. Two tables and four diagrams. (Great Britain) G Hoyle and M A Ramsbuttom, Special Report No 92, Iron and Steel
37 997. Application of vacuum metallurgical processes to the manufacture of uranium carbide fuels. (USA) Various manufacturing processses for the production of uranium monocarbide fuel elements are described and compared, the treated material to have certain specified properties including close limits for the carbon content. The methods evaluated included vacuum induction casting, consumable electrode skull casting, a vacuum carbon-arc skull casting process, an electron beam skull casting process, and a melt stock manufacturing process based on the carbothermic reduction of UO~ utilizing a vacuum induction furnace. The relative merits of the different processes are discussed in detail. D H Turner, Trans Vac Metall Conference, 1964, Amer Vnc Soc,
Institute, London, November 1965, (in press}.
Boston, Mass, (1965), pp 306-315.
Britain) A G MeMillan et al, Special Report No 92, Iron and Steel Institute,
London, November 1965, (in press).
37 : 53 993. Vacuum degassiug of high alloy steels: Part 2. (Great Britain) This paper describes some practical aspects together with technical and commercial advantages of steel-making practice as applied to the BISRA continuous degassing plant. They also discuss in detail the defects in En. 52 and 59 valve steel which vacuum treatment eliminates together with the associated test procedures. Two tables, eight diagrams. (Great Britain) D Hall et al, Special Report No 92, Iron and Steel Institute, London,
November 1965, (in press}. 37 : 53 994. Some aspects of the vacuum treatment of bulk steels for the wire drawing industry. (Great Britain) A consideration of the demands of the wire drawing industry with respect to the quality of the company's products and the need for replacing some of the grades with low alloy materials led to proposals being made in 1961 that the facilities of one of the steel plants at the Irlam Works of LSCM be extended by the addition of a 120ton D o r t m u n d Hoerder type vacuum degassing unit at Lancashire Steel Manufacturing Company. Finally some of the technical benefits, such as improved cold
37 : 41 998. Progress of the remelting technique for steels in vacuum are furnaces. (USA) Improvements in the control of the arc length and in the manner in which electrodes are prepared have contributed to a uniform remelting process which results in fewer inhomogeneities in the ingot. By controlling the arc and the molten pool, it is possible to obtain freckle-free ingots of high-strength steel. Ingots of high-speed steel with a uniform as-cast structure and small carbide grains can be produced by a modified remelting technique. The electron beam furnace offers further possibilities for the improvement of mechanical properties of special steels. The temper embrittlement of a highstrength steel can be eliminated by a slow remelting. Also, the fatigue properties can be improved by similar procedures. (Author) I Sperner, Trans Vac Metall Conference, 1964, Amer Vac Soc,
Boston, Mass, (1965), pp 354-365. 37:47 999. Some factors affecting (steel) degassing by the R-H circulating flow process. (USA) The equipment described in this paper consists essentially of an evacuated chamber provided with two pipe-leg extensions which are
613