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试验与生产实践的结果表明,铬钼铜铸铁是一种耐热、耐蚀与耐磨性较好的材料,广泛用于制造内燃机的气阀座,因为气阀座(特别是高速增压柴油机)是在复杂而恶劣的条件下工作的,工作温度可达到500～800℃,同时还在含有CO、CO_2、NO_X、SO_2与H_2S等侵蚀性介质的废气的腐蚀下,与气阀进行着磨擦。如果气阀座磨损严重,内燃机燃烧室的气密性被破坏,其动力性和经济性大受损失。目前用于制造柴油机气阀座的铬钼铜铸铁有两种:一种是含Cr 0.3～0.6％、Mo 0.3～0.6％与Cu 0.8～1.2％的低铬钼铜铸铁,铸态使用,或车成半成品之后镀铜、等温淬火(HRc27～31)后使用;一种是铸态使用的含Cr 0.6～1.0％、Mo 0.6～1.0％与Cu 0.8～1.2％的中铬钼铜铸铁。
Test and production practice results show that chromium molybdenum copper cast iron is a heat, corrosion and wear resistance of the material is widely used in the manufacture of internal combustion engine valve seat, because the valve seat (especially high-speed supercharged diesel engine ) Is working under complex and harsh conditions, the working temperature can reach 500 ~ 800 ℃, and also with the corrosion of the exhaust gas containing CO, CO_2, NO_X, SO_2 and H_2S and other aggressive media, and the valve friction . If the valve seat wear and tear, the airtightness of the combustion chamber of the internal combustion engine is destroyed, its power and economic loss greatly. There are currently two types of chromium molybdenum cast iron used to make diesel valve seats: one is a low chromium molybdenum cast iron containing 0.3-0.6% Cr, 0.3-0.6% Mo and 0.8-1.2% Cu, as cast, or The car into a semi-finished products after the copper, isothermal quenching (HRc27 ~ 31) after use; one is used in the cast containing Cr 0.6 ~ 1.0%, Mo 0.6 ~ 1.0% and Cu 0.8 ~ 1.2% of the Cr-