回火工艺对K110冷作模具钢组织性能的影响

Effect of Tempering Process on Microstructure and Properties of K110 Cold Work Die Steel

利用不同的回火工艺对经真空淬火、深冷处理后的K110冷作模具钢进行回火处理,利用金相显微镜对钢进行组织分析,利用X射线衍射仪进行物相分析,利用洛氏硬度计进行硬度检测.结果表明:K110冷作模具钢经真空淬火、深冷处理、高温回火后的组织为大块一次碳化物;弥散分布于基体中的粒状碳化物;回火索氏体;隐针、针状马氏体以及残余奥氏体.提高回火温度后,组织中一次碳化物尺寸无明显变化,弥散分布的粒状碳化物含量增加,部分粒状碳化物尺寸变大,组织中残余奥氏体含量降低,硬度降低.与K110、SLD相比,Cr12Mo1V1冷作模具钢中的一次碳化物粗大且呈网状,组织较差.

K110 cold work die steel is subjected to vacuum quenching and cryogenic treatment after different tempering processes.Metallographic microscope is used to observe the steel microstructure,and X-ray phase analysis and rockwell hardness test are conducted.The results show that the microstructure of the K110 cold work die steel after vacuum quenching,cryogenic treatment and high temperature tempering is consisted of bulk primary carbides,granular carbides dispersed in the matrix,tempered soxite,hidden needles and needle-shaped horses martensite and retained austenite.After increasing the tempering temperature,the size of the primary carbides in the structure did not change significantly,the content of the dispersed granular carbides is increased,the size of some granular carbides became larger,the residual austenite content in the structure is decreased,and the hardness is decreased.Compared with K110 and SLD,the primary carbides in the Cr12Mo1V1 cold work die steel are coarse and reticulate,and the microstructure is poor.