热处理对D-5S高Ni球铁组织及力学性能的影响  

Effect of Heat Treatment on Microstructure and Mechanical Properties of D-5S Ductile Iron with High Amount of Ni

作　　者：王志斌[1] 徐锦锋[1] 翟秋亚[1] 高军 朱铭 程武超 赵新武 

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048 [2]江苏多为泵业股份有限公司,江苏大丰224115 [3]西峡县内燃机进排气管有限责任公司,河南西峡474500

出　　处：《现代铸铁》2014年第6期15-21,共7页Modern Cast Iron

摘　　要：详细介绍了利用正交试验方法研究热处理工艺对D-5S高Ni奥氏体球墨铸铁中碳化物体积分数和形态以及合金性能的影响规律.结果表明：加热速度越低、保温温度越高、冷却速率越快时,合金碳化物体积分数越少.合理的热处理工艺可以大幅度提高高Ni球铁的力学性能.推荐的热处理工艺参数为：加热速度100 ℃/h,加热温度975C,保温时间3h,出炉空冷.热处理态合金组织由奥氏体枝晶、球状石墨和弥散于晶间的二次碳化物组成,碳化物体积分数小于2.20％.合金硬度154～160 HBS,抗拉强度546～550 MPa,伸长率24％～28％.The effect of heat treatment on the amount and morphology of carbide in high-Ni D-5S ductile iron by orthogonal experiment was introduced.The results indicated that lower heating rate,higher holding temperature and faster cooling rate were beneficial to reduce the carbides.Reasonable heat treatment process could significantly improve the mechanical properties of high Ni ductile iron.Recommended heat treatment process parameters were as follows：heating rate was 100 ℃/h,the heating temperature was 975 ℃,holding time was 3 hours and then cooled in air.The microstructures after heat treated were austenite dendrites,spheroidal graphite and secondary carbide dispersed in crystal lattice.The carbide volume fraction was less than 2.20％.Hardness of the alloy was between 154～160 HBS.Tensile strength was between 546～550 MPa and the elongation was between 24％～28％.

关 键 词：高Ni球铁 热处理工艺 碳化物体积分数 硬度 

分 类 号：TG255[金属学及工艺—铸造]