Patent ID: 6432477
Filing Date: 2002-08-13
Classification: C04B,C23C,F16D,H05B

Abstract:
A method of infiltrating different portions of a porous preform body with carbon by heating the body to a temperature at which carbon-containing gas is crackable to deposit carbon in the pores thereof, the method comprising placing the body adjacent a multi-portion heating element shaped into substantially concentric coils so that the coils thereof align with corresponding portions of the body, and supplying power to the heating element to heat the body whilst exposing the body to a crackable carbon-containing gas whereby carbon is deposited in the pores of the heated portion; and including the step of selectively energising different coils of the multi-portion heating element to create a thermal gradient between one heated body portion and the or each adjacent body portion so as to propagate an infiltration front from the centre to the periphery of the preform body and selectively deposit carbon in the pores of each different heated body portion to provide a graphitisable rough laminar structure.