45钢激光WC合金化组织与性能的研究

Research on Microstructure and Property of Laser WC Alloying on 45 Steel Surface

在45钢表面进行了碳化钨(WC)激光合金化实验,利用金相显微镜、维氏硬度计等设备检测了合金化层的组织和性能。实验表明:激光合金化层组织致密,晶粒细化,与基体呈冶金结合。其中,合金化区为含碳量过饱和的奥氏体树枝晶组织,热影响区为板条状淬火马氏体组织。合金化区平均硬度700 HV0.2,相变硬化区平均硬度550 HV0.2,硬度呈梯度过渡。通过与氮化试样的比较,表明激光合金化试样的强化层深度、平均硬度均高于氮化试样。45钢零件经激光合金强化后,使用寿命大大提高。

The experiment of laser WC alloying on 45 steel surface was made.The microstructure and properties of laser alloying layer and nitriding layer were studied using OM and hardness tester.The results show that the microstructure of laser alloying zone is compact,grain is fine,and has metallurgical bonding with matrix.The microstructure of cellular dendritic appears in alloying zone.Lath martensite is found in heat-affected zone.The average hardness of alloying zone is 700 HV0.2.The average hardness of phase-change hard zone is 550 HV0.2 with gradient descent.Compared with nitriding specimen,laser alloying layer has better properties such as minute crystals,deeper layer,higher hardness and good metallurgical bonding with base metal.Using laser alloying,the good wear layer can be made on 45 steel surface which can greatly increase the part work life.