الفهرس 
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Abstract
Various destabilization heat treatments at 880° C, 980° C, 1080° C, and 1180° C for one hour and quenching in various cooling media (Air, Water, and Oil) followed by tempering at 500° C for two hours were conducted on 2.55 wt.%-C, 21.8 wt.% Cr high chromium white cast iron alloy. Investigations were carried out on high chromium white cast iron alloy including microstructure and mechanical characteristics. The obtained hardness values are the result of the mixture of the martensite formed, stoichiometry and morphology of the secondary carbides present mainly M7C3. Maximum hardness (804 HV) was obtained for the sample that was treated at 1080° C for one hour and quenched in water followed by tempering at 500 for two hours. This high hardness has of course a positive impact on the wear resistance. Minimum wear rate (8.1*10-6 gm/sec) was obtained for the sample that was heat treated at 880° C for one hour and quenched in oil followed by tempering at 500° C for two hours due the massive amount of M7C3 & M23 C6 carbides imbedded in the matrix. Optimum mechanical properties for the investigated high chromium white cast iron can be obtained by applying a thermal treatment at 980° C for one hour and quenching in water.