| 摘要 |
Treatment of a porous carbon workpiece (WP) with liquid silicon (lSi) to form silicon carbide (SiC) involves (a) preheating under inert gas to a temperature TB1, (b) optionally reducing pressure to 100 hPa or less, (c) impregnating with lSi at pressure pB2 and temperature TB2, (d) reacting at temperature TB3 (not less than TB2), in the absence of lSi outside the WP, to form SiC, (e) gassing with inert gas and cooling to conditioning temperature Tk and (f) cooling to room temperature. An independent claim is included for apparatus for carrying out the process, comprising at least four, separately heatable, coolable, evacuable and gas purgable chambers (O1 - O4), connected by air locks (10, 20, 30, 40). In the case of four chambers, one chamber is used for steps (a) and (b); one for step (c); one for steps (d) and (e); and one for step (f). In the case of six chambers, separate chambers are used for steps (a) and (b) or for step (d) and (e). In the case of six chamber each of steps (a) - (f) is carried out in separate chamber. |
