Cr28铸铁热处理工艺的研究

Study on Heat Treatment Process of Cr28 Casting Iron

研究了热处理工艺对Cr28铸铁的组织和性能的影响。结果显示,正火回火处理后,Cr28铸铁的组织由初生碳化物、共晶碳化物、二次碳化物、马氏体和残余奥氏体组成;随正火温度的提高,材料的硬度先升后降,1 040℃正火后有极大值61．6HRC,冲击韧度呈逐渐升高趋势,但总体变化幅度较小(4．1-6．9 J／cm2) ;1040℃正火后, 随回火温度升高,材料的硬度逐渐降低,冲击韧度变化范围较小(3．7-4．3 J／cm2)。分析了不同热处理工艺处理后,材料性能变化的原因。

The microstructure and properties of Cr28 casting iron after different heat treatment process were studied. The results show that Cr28 casting iron consists of primary earbide,eutectic carbide,secondary earbide,martensite and austenite. As austenitizing temperature rising, the hardness of the casting iron falls after rising and maximum is 61.6 HRC after normalized at 1 040℃, the toughness is from 4.1 J/cm^2 to 6.9 J/cm^2. As the is tempering temperature rising after normalized at 1 040℃, the hardness of Cr28 casting iron reduces gradually and the toughness changing is from 3.7 J/cm^2 to 4.3J/cm^2. The reasons for properties change after different heat treatment process were analgzed.