电渣熔铸钢结硬质合金经激光熔化处理后的组织和性能

Microstructure and Properties of Steel-bonded Carbide by Electro-slag Melting and Casting after Laser Melted Treatment

借助光学显微镜、扫描电镜及XRD衍射仪对重熔层的显微组织结构和相结构进行分析,用显微硬度计和MM-200型磨损试验机对激光处理表面的硬度和耐磨性进行了测试。试验结果表明,电渣熔铸钢结硬质合金表面经过激光重熔处理后的组织比未经激光处理的明显细化,大颗粒WC部分溶解,小颗粒碳化物完全溶解;随着激光功率的加大,重熔层的熔深增大,枝晶尺寸随之增大,表面硬度和耐磨性也相应提高。

The surface of steel-bonded carbide DGJW40 prepared by electro-slag melting and casting was treated by 002 laser with the same scanning speed （800 mm/min） and four kinds of laser powers （four kinds of laser powers）, and the microstructure and properties of this alloy surface layer were studied by OM, SEM, XRD, micro-hardness tester and MM-200 wear tester. The results show that the microstructure after laser remelting is much finer than that without laser treatment, and some big WCp are partly dissolved and some small WCp are completely dissolved. The depth of remelted pool and the size of dendrites are increased with increase of the laser powers, thus results in the increase of surface hardness and wear resistance.