铬对CADI组织及性能的影响  

Effects of Chromium on Microstructures and Properties of Carbide Austempered Ductile Iron

作　　者：张婷[1] 孙玉福[1] 赵靖宇[1] 刘金庆[1] 吴娜[1] 徐栩[1] 

机构地区：[1]郑州大学材料科学与工程学院,河南郑州450002

出　　处：《铸造》2009年第11期1154-1157,共4页Foundry

摘　　要：通过金相观察、X射线衍射分析、能谱分析、洛氏硬度、冲击韧度及耐磨性试验,研究了铬对含碳化物等温淬火球墨铸铁(CAD)I的组织、力学性能及耐磨性能的影响。结果表明,经过920℃的奥氏体化保温1.5h及280℃等温淬火保温2h热处理后,含铬0.5%的试样组织及综合性能最佳,其铸态组织为65%珠光体+铁素体+碳化物,热处理后其组织为下贝氏体+15%碳化物+残余奥氏体,抗拉强度σb为1420MPa,硬度为HRC50.9,冲击韧度为21.37J·cm-2,相对耐磨性比不加铬时提高了48%。By using of microstructure observation, X-ray diffraction analysis, spectrum analysis, Rockwell hardnesstest, impact toughness and wear resistance experiment, the effects of chromium on microstructure and properties of carbide austempered ductile iron （CADI） were researched. The results show that after austenite at 920 ℃ for 1.5 h and austempered at 280 ℃ for 2 h, the microstructure and the properties of the sample containing 0.5% chromium are the optimal; the as-cast microstructure is composed of 65% pearlite, ferrite and carbide; after heat treatment, the microstructure is composed of remaining austenite, lower bainite and 15% carbide. Its tensile strength is 1 420 MPa, hardness HRC is 50.9, impact toughness is 21.37 J .cm-2 and relative wear resistance is increased by 48% than that of samples contain none chromium.

关 键 词：CADI 铬 碳化物 硬度 耐磨性 

分 类 号：TG115[金属学及工艺—物理冶金]