中国激光, 2010, 37 (1): 250, 网络出版: 2010-01-16
35CrMoA钢激光淬火渗氮复合处理微观组织与性能
Microstructure and Properties of 35CrMoA Steel in Laser Quenching-Nitriding
摘要
对35CrMoA钢进行激光淬火渗氮复合处理,采用光学显微镜(OM)、X射线衍射仪(XRD)、透射电镜(TEM)、显微硬度计及磨擦磨损试验研究了激光淬火/渗氮层的显微组织、硬度及耐磨性能,并与气体渗氮层对比。结果表明,两种渗氮层均由ε相,相,Cr2N相及Fe3C组成。激光淬火/渗氮白亮层中ε-Fe3N含量较高,而脆硬的ζ-Fe2N相及Fe2O3含量较低,且Cr2N颗粒细小。扩散层中-Fe4N中存在超点阵结构,Fe原子和N原子在相中有序排列,相和α-Fe相存在一定的位向关系,二者的共格性和相容性优良,细小渗碳体分布在条状下贝氏体组织中。激光淬火/渗氮试样的磨损表面划痕较浅,而气体渗氮试样表面有较深的犁沟,局部区域存在剥落,激光淬火/渗氮复合处理使渗氮层深度增加,硬度提高,耐磨性增强。
Abstract
Laser quenching and nitriding treatment are performed on 35CrMoA steel,and the microstructure,hardness and wear resistance of laser quenching/nitrided layer were investigated by means of optical microscope (OM),X-ray diffractomer (XRD),transmission electron microscope (TEM),microhardness tester and wear equipment compared with the gas nitrided layers. The results show that,both nitrided layer consist of ε,,Cr2N and Fe3C.The content of ε-Fe3N is higher in the laser quenching/nitrided white layer while the contents of the brittle ζ-Fe2N and Fe2O3 are lower than that of the gas nitrided layer,and the Cr2N particles are much finer. The ultra lattice structure exist in -Fe4N in the diffusion layer,in which the Fe and N atom arrange orderly. There are phase relation,coherence and compatibility between -Fe4N and α-Fe. Spherical particles of cementite are formed in lower strip bainite. The scratch in worn surface of laser quenching/nitrided layer is shallow,but the gas nitriding worn surface has deep plow furrow and flaking. After laser quenching/nitriding treatment,the depth of the nitrided layer increases,and hardness as well as wear resistance are improved dramatically.
程义远, 王勇, 韩彬, 李美艳. 35CrMoA钢激光淬火渗氮复合处理微观组织与性能[J]. 中国激光, 2010, 37(1): 250. Cheng Yiyuan, Wang Yong, Han Bin, Li Meiyan. Microstructure and Properties of 35CrMoA Steel in Laser Quenching-Nitriding[J]. Chinese Journal of Lasers, 2010, 37(1): 250.