Mo对高硬度镍基合金激光熔覆层组织和耐磨性的影响

采用激光熔覆技术, 在45#钢表面进行了镍基合金粉末添加Mo的熔覆试验,通过对激光熔覆工艺参数及Mo含量的优选,获得了成形良好、无裂纹、组织致密的熔覆层。对熔覆层横断面进行了显微硬度测量和显微组织分析,对各种Mo含量的熔覆层试样进行了摩擦磨损试验。结构表明:Mo能够提高高硬度镍基合金激光熔覆层的韧性、耐磨性,细化熔覆层的组织,降低熔覆层的裂纹敏感性。Mo对Ni60镍基合金激光熔覆层的改善归因于Mo对熔覆层组织的均匀细化、对粗大针状脆性硬质相的抑制以及对韧性相成分的提高作用。

Effect of Mo-doping on the Microstructure and Wear Properties of Laser-clad Nickel-based Coatings

The experiments of 1aser-clad Ni-base allo y powder doped with and without Mo were carried out. Various technical parameters and different Mo content were chosen to obtain a perfect clad layer. The micros tructure observation and micro-hardness test of the cross-section of the laser-c ladding zone were performed. The frictional wear tests of various Mo content wer e accomplished, also. The results indicate that the addition of Mo can enhance t he toughness, refine the microstructure and reduce the cracking susceptibility o f laser-clad nickel-base coatings obviously. The improvement of properties of th e laser-clad layer is due to the effect of Mo on it, in which Mo with a proper c ontent can uniformly refine the structural grains, suppress the formation of big needle brittle hard phases entirely and increase the tenacity of coatings.