| 摘要 |
1341696 Fibre reinforced carbon bodies PLESSEY CO Ltd 19 April 1971 [6 Feb 1970] 5863/70 Heading C1A A carbon body reinforced with high modulus carbon fibres which are under longitudinal stress in the carbonaceous matrix of the body is prepared by forming a body conisting of partlyfired carbon fibres and an uncured phenolic resin; heat treating the body to cure the resin and produce a body containing partly fired carbon fibres in a cured resin matrix and then carbonizing the body under conditions such that the partly fired carbon fibres are converted into high modulus carbon fibres, said partly fired carbon fibres being produced from fibres of organic fibre material suitable to produce high modulus carbon fibres by heating said organic fibres in an oxidizing atmosphere as required by such production so that the conversion of such partly fired fibres to high modulus carbon fibres requires no further contact with oxygen, and said longitudinal stress being ensured by maintaining the fibres under mechanically applied longitudinal stress during curing and carbonization of the resin or by the use of partly fired carbon fibres whose longitudinal shrinkage when unrestrained during carbonization exceeds the corresponding shrinkage of the resin matrix or by a combination of these two methods. Preferably the fibres in the resin are fibres which have been prevented from shrinking whilst being subjected to the oxidizing atmosphere. The fibres are preferably obtained from polyacrylonitrile. |
