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Interfacial properties of some high-strain carbon fibers in an epoxy matrix
I
resutv¢
i I
reg.wt
Prepared by M. E. Adams, L. Boniface, M. C. Hi/land 7". Nensi
CARBON FIBRES Advances in UHM carbon fibers: production, properties and applications Schulz, D. A. SAMPE Journal Vo123 No 2 (March~April 1987) pp 27-31 The carefully-controlled processing steps required to produce ultra-high modulus carbon fibres from pitch on a large scale are described. The use of these P-100 fibres as reinforcements in 6061 aluminium matrix wire is discussed and suggestions for further refinements for future uses are given. Blending mesophase pitch to improve its properties as a precursor for carbon fibre: Part 1: blending of PVC pitch into coal tar and petroleum-derived mesophasc pitches Mochida, I., Toshima, H., Korai, Y. and Matsumoto, T. Journal of Materials Science Vo123 No. 2 (February 1988) pp 670-677 The suitability of using mesophase pitches blended with isotropic PVC-based pitches as a precursor for producing carbon fibres is assessed by measuring the tensile strength and carbonization reactivity of the resulting fibres. The miscibility of the pitches is measured by the optical texture of the blend. Blending was successful for coal tar based pitch but not for petroleum based pitch due to immiscibility. Although there is no significant improvement in the tensile properties of the fibres, blending reduced the time required for stabilization of the fibres by oxidation. Development of low distortion tooling for high precision space components Zimcik, D. G. and Gietz, J. G. SAMPE Journal Vol 23 No 3 (May~June 1987) pp 11-16 Experimentally measured thermal distortion design data on monolithic graphite (Airco Carbon XM-332) tooling material and drapable graphite tooling foam (Compform 374) are presented. The test results from a representative mould of a SHF antenna reflector for communications satellite applications are also given. The results of the work suggest that the monolithic graphite tooling may have applications for a limited run of dimensionally critical components. Interfacial properties of some high-strain carbon fibers in an epoxy matrix Rich, M. J. and Drzal, L. T. Journal of Reinforced Plastics and Composites Vol 7 (March 1988) pp 145-153 Interracial parameters, including fibrematrix bond strength and failure mechanisms of two high strain carbon fibres, AS6 and IM6, have been evaluated and compared to two intermediate strain fibres, AS1 and AS4. It is concluded that high strain fibres show promise of enhancing composite properties if the strain potential of the matrix can be improved.
414
Modification of mesophase pitch by blending: Part 2: modification of mesophase pitch fibre precursor with thermoresisting polyphenylencoxide Mochida, I., Toshima, H., Korai, Y. and Matsumoto, J. Journal of Materials Science Vo123 No 2 (February 1988) pp 678-686 PPO is incorporated into petroleum-based pitch precursor fibres to improve their stability prior to oxidative stabilization. The PPO is dispersed homogeneously along the pitch fibres axis at the spinning stage and disappears in the centre of the fibres after oxidation (at 250°C) and carbonization (at 1300°C). The presence of residual PPO in the skin of the fibre is explained in terms of the lower fusibility of the pitch surface after extensive cross-linking during the oxidation stage. The mechanical strength of carbon fibres from the blended pitch is reduced due to porosity created by partial decomposition of the PPO on spinning. The strength-length relationship for carbon fibres Phani, K. K. Composites Science and Technology Vo130 No 1 (1987) pp 59-71 A modification of the Weibull-type flaw distribution function is suggested for analysing the strength distribution of carbon fibres. Strength distribution of Type I and Type II carbon fibres, reported by other workers, are analysed in terms of the proposed distribution and strength distribution data for fibres of 50 mm length used to predict strengths at shorter lengths (5mm and 0.5mm). Good agreement is found between predicted and experimental values. Structure of mesophase pitch-based carbon fibres Endo, M. Journal of Materials Science Vo123 No 2 (February 1988) pp 598-605 Microstructure-property relationships are compared for five types of ultra-high modulus carbon fibres produced from mesophase pitch and high modulus PAN-based fibres. The fibres are examined by X-ray diffraction, SEM, TEM and transverse magnetoresistance measurements (which indicate degree of graphitization). The folded turbostratic layer structure found in some fibres confers higher elongation and strength than the three-dimensional graphitic structure revealed in other fibres. A study of the surface of carbon fiber by means of X-ray photoelectron spectroscopy llI Youxian, D., Dianxun, W., Mujin, S., Chuanzheng, C. and Jin, Y. Composites Science and Technology Vol 30 No 2 (1987) pp 119-126 The results of examining the surface of carbon fibres which had been treated by various methods (namely, with oxygen plasma, withnitrogen plasma, by anodic oxidation, or with 65% nitric acid) using XPS are
reported and discussed. It was found that no matter which method of treatment was adopted, active oxygen-containing groups were present on the surface of the fibre. The concentration of the groups increased with treatment time but tended to an equilibrium value. The presence of these active groups was thought to improve the adhesion of the fibres to a matrix material. Uniaxial compressive strength of high modulus fibres for composites Kumar, S., Adams, W. W. and Helminiak, T. E. Journal of Reinforced Plastics and Composites Vol 7 (March 1988) pp 108-119 The compressive properties of carbon and high modulus organic fibres has been discussed in relation to their density and structure. Possible models are proposed to explain the high compressive strength of the low density carbon fibre. Wide and small angle scattering data are presented to support the models proposed.
CEMENT MA TRICES Experiments on the transmission of forces over cracks in fibre reinforced concrete Van de Loock, L. Journal of Materials Science Letters Vol 7 (1988) pp 225-226 Push-off tests have been carried out to measure the normal and shear forces transmitted over cracks in steel fibre reinforced concrete. It was found that the steel fibres had no significant influence on the crack opening path or the normal forces. The shear stress was much higher for the reinforced concrete. Strength of steel-fibre-reinforced polymer concrete: effect of impregnation technique Giindiiz, G. and Yal~in, N. Composites Science and Technology Vol 30 No 2 (1987) pp 127-135 The effects of pressure- and vacuumimpregnation on the flexural strength of steel-fibre-reinforced and polymerimpregnated concrete was investigated. While the combination of steel fibre reinforcement and polymer impregnation was found to give the best improvement to the strength of the concrete, impregnation by pressure resulted in a higher increase in strength compared to vacuum impregnation at the same polymer loadings.
CERAMIC FIBRES Characterization and surface modification on silicoaluminate glass fibre Fernandez, A., Nietto, Ma. I. and Oteo, J. L. Journal of Materials Science Letters Vol 7 (1988) pp 7-8
COMPOSITES. SEPTEMBER 1988
resutv¢
i I
reg.wt
Prepared by M. E. Adams, L. Boniface, M. C. Hi/land 7". Nensi
CARBON FIBRES Advances in UHM carbon fibers: production, properties and applications Schulz, D. A. SAMPE Journal Vo123 No 2 (March~April 1987) pp 27-31 The carefully-controlled processing steps required to produce ultra-high modulus carbon fibres from pitch on a large scale are described. The use of these P-100 fibres as reinforcements in 6061 aluminium matrix wire is discussed and suggestions for further refinements for future uses are given. Blending mesophase pitch to improve its properties as a precursor for carbon fibre: Part 1: blending of PVC pitch into coal tar and petroleum-derived mesophasc pitches Mochida, I., Toshima, H., Korai, Y. and Matsumoto, T. Journal of Materials Science Vo123 No. 2 (February 1988) pp 670-677 The suitability of using mesophase pitches blended with isotropic PVC-based pitches as a precursor for producing carbon fibres is assessed by measuring the tensile strength and carbonization reactivity of the resulting fibres. The miscibility of the pitches is measured by the optical texture of the blend. Blending was successful for coal tar based pitch but not for petroleum based pitch due to immiscibility. Although there is no significant improvement in the tensile properties of the fibres, blending reduced the time required for stabilization of the fibres by oxidation. Development of low distortion tooling for high precision space components Zimcik, D. G. and Gietz, J. G. SAMPE Journal Vol 23 No 3 (May~June 1987) pp 11-16 Experimentally measured thermal distortion design data on monolithic graphite (Airco Carbon XM-332) tooling material and drapable graphite tooling foam (Compform 374) are presented. The test results from a representative mould of a SHF antenna reflector for communications satellite applications are also given. The results of the work suggest that the monolithic graphite tooling may have applications for a limited run of dimensionally critical components. Interfacial properties of some high-strain carbon fibers in an epoxy matrix Rich, M. J. and Drzal, L. T. Journal of Reinforced Plastics and Composites Vol 7 (March 1988) pp 145-153 Interracial parameters, including fibrematrix bond strength and failure mechanisms of two high strain carbon fibres, AS6 and IM6, have been evaluated and compared to two intermediate strain fibres, AS1 and AS4. It is concluded that high strain fibres show promise of enhancing composite properties if the strain potential of the matrix can be improved.
414
Modification of mesophase pitch by blending: Part 2: modification of mesophase pitch fibre precursor with thermoresisting polyphenylencoxide Mochida, I., Toshima, H., Korai, Y. and Matsumoto, J. Journal of Materials Science Vo123 No 2 (February 1988) pp 678-686 PPO is incorporated into petroleum-based pitch precursor fibres to improve their stability prior to oxidative stabilization. The PPO is dispersed homogeneously along the pitch fibres axis at the spinning stage and disappears in the centre of the fibres after oxidation (at 250°C) and carbonization (at 1300°C). The presence of residual PPO in the skin of the fibre is explained in terms of the lower fusibility of the pitch surface after extensive cross-linking during the oxidation stage. The mechanical strength of carbon fibres from the blended pitch is reduced due to porosity created by partial decomposition of the PPO on spinning. The strength-length relationship for carbon fibres Phani, K. K. Composites Science and Technology Vo130 No 1 (1987) pp 59-71 A modification of the Weibull-type flaw distribution function is suggested for analysing the strength distribution of carbon fibres. Strength distribution of Type I and Type II carbon fibres, reported by other workers, are analysed in terms of the proposed distribution and strength distribution data for fibres of 50 mm length used to predict strengths at shorter lengths (5mm and 0.5mm). Good agreement is found between predicted and experimental values. Structure of mesophase pitch-based carbon fibres Endo, M. Journal of Materials Science Vo123 No 2 (February 1988) pp 598-605 Microstructure-property relationships are compared for five types of ultra-high modulus carbon fibres produced from mesophase pitch and high modulus PAN-based fibres. The fibres are examined by X-ray diffraction, SEM, TEM and transverse magnetoresistance measurements (which indicate degree of graphitization). The folded turbostratic layer structure found in some fibres confers higher elongation and strength than the three-dimensional graphitic structure revealed in other fibres. A study of the surface of carbon fiber by means of X-ray photoelectron spectroscopy llI Youxian, D., Dianxun, W., Mujin, S., Chuanzheng, C. and Jin, Y. Composites Science and Technology Vol 30 No 2 (1987) pp 119-126 The results of examining the surface of carbon fibres which had been treated by various methods (namely, with oxygen plasma, withnitrogen plasma, by anodic oxidation, or with 65% nitric acid) using XPS are
reported and discussed. It was found that no matter which method of treatment was adopted, active oxygen-containing groups were present on the surface of the fibre. The concentration of the groups increased with treatment time but tended to an equilibrium value. The presence of these active groups was thought to improve the adhesion of the fibres to a matrix material. Uniaxial compressive strength of high modulus fibres for composites Kumar, S., Adams, W. W. and Helminiak, T. E. Journal of Reinforced Plastics and Composites Vol 7 (March 1988) pp 108-119 The compressive properties of carbon and high modulus organic fibres has been discussed in relation to their density and structure. Possible models are proposed to explain the high compressive strength of the low density carbon fibre. Wide and small angle scattering data are presented to support the models proposed.
CEMENT MA TRICES Experiments on the transmission of forces over cracks in fibre reinforced concrete Van de Loock, L. Journal of Materials Science Letters Vol 7 (1988) pp 225-226 Push-off tests have been carried out to measure the normal and shear forces transmitted over cracks in steel fibre reinforced concrete. It was found that the steel fibres had no significant influence on the crack opening path or the normal forces. The shear stress was much higher for the reinforced concrete. Strength of steel-fibre-reinforced polymer concrete: effect of impregnation technique Giindiiz, G. and Yal~in, N. Composites Science and Technology Vol 30 No 2 (1987) pp 127-135 The effects of pressure- and vacuumimpregnation on the flexural strength of steel-fibre-reinforced and polymerimpregnated concrete was investigated. While the combination of steel fibre reinforcement and polymer impregnation was found to give the best improvement to the strength of the concrete, impregnation by pressure resulted in a higher increase in strength compared to vacuum impregnation at the same polymer loadings.
CERAMIC FIBRES Characterization and surface modification on silicoaluminate glass fibre Fernandez, A., Nietto, Ma. I. and Oteo, J. L. Journal of Materials Science Letters Vol 7 (1988) pp 7-8
COMPOSITES. SEPTEMBER 1988