a group of oxidation-resistant and heat-resistant steels alloyed with Cr (5-14 percent) and Si (1-3 percent). Depending on the desired level of performance characteristics, Silcrome may be subjected to further alloying with Mo (up to 0.9 percent) or Al (up to 1.8 percent). Silcrome resists oxidation upon exposure to air and in sulfur-bearing media up to 850°-950°C. It is primarily used in the manufacture of valves for internal-combustion engines and parts for boiler installations and fire bars. Under increased mechanical loads, components made from Silcrome display reliable operation for a prolonged period of time at temperatures up to 600°-800°C. Grades of Silcrome produced in the USSR include 4Kh9S2 and 4KhlOS2M.