| 摘要 |
PROBLEM TO BE SOLVED: To improve the heat resistance and wear resistance of an alloy by preheating a preform composed of ceramic short fibers or whiskers and thereafter, force-fitting the molten metal of high chromium cast iron therein. SOLUTION: Preferably, as ceramic short fibers, the ones of alumina series, alumina-silica series or silicon carbide series are used and as whiskers, the ones of silicon carbide series, zirconia series, silicon nitride series, potassium titanate series, magnesia series or calcium series are used. As high chromium cast iron, hypo-eutectic high chromium cast iron or hyper-eutectic high chromium cast iron contg. 2 to 35% wt.% Cr and 2 to 5 wt.% C is preferably used. As a preform, the one in which the volume fractinal ratio of the ceramic shrot fibers or the whiskers is 8 to 50% is preferable. For force-fitting the molten metal to all the corners of the preform, the preform is preheated and the preheating temp. is controlled to the one equal to or below the m.p. of the molten metal.
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