45~#碳钢表面激光铬镍合金化及其耐磨性的研究

作者利用1.1kW CO_2激光器对45~#碳钢表面进行了激光铬镍合金化处理。通过对合金层的成分和相组织分析,以及对合金层和基体的硬度与耐磨性的研究认为,激光铬镍合金化层的组织是胞状枝晶,其相组成为马氏体加残余奥氏体。测试结果表明,合金层的显微硬度是45~#碳钢基体的2～3倍,耐磨性也明显地比基体材料的好。

Laser Alloying with Chromium and Nickel on the Surface of 45~# Carbon Steel and its Wear Resistance

The laser alloying of 45,carbon steel surface with chromium and nickel using 1.1 kW CO2 laser has been realized. Through analysing content of alloying elements and phase structure of the alloyed layer, measuring microhardness and wear resistance of substrate and alloyed layer, it has been shown that the structure of alloyed layer is a cellular dendrite and the phases of alloyed layer consist of martensite and residual auste-nite. This phase constitution is decided upon the content of elements (Cr, Ni) contained in alloyed layer and solidifying speed accompanied by high-speed cooling during the alloying. The test results showed that the microhard -ness of alloyed layer is 2-3 times of that of 45* carbon steel substrate, and the wear resistance of the former is much better than the original.We considered that the improving of the wear-resistance of the alloyed layer is related to the increase of the surface hardness.