多元硬质合金覆层材料力学性能的研究

Research on Mechanical Property of Multiple Hard Alloy Cladding Material

为提高钢材表面的耐磨损和耐腐蚀能力,以Mo粉、Fe-B合金粉和Fe粉为基本原料,加入WC、Cr3C2、TiC等碳化物硬质相和C、Ni、Cr等合金元素,采用真空液相烧结工艺,在Q235钢基体上制备多元硬质合金覆层材料。对覆层材料进行了洛氏硬度测试及弯曲强度测试,结果表明:CW系覆层材料的硬度达到HRA84.8,是Q235钢基体硬度的2.3倍;CW系覆层材料的弯曲强度值达到1175.52MPa,是Q235钢基体弯曲强度的1.4倍;掺加碳化物硬质相显著提高了Mo2FeB2硬质合金覆层材料的硬度和弯曲强度。利用扫描电镜观察了硬质合金覆层以及覆层-钢基体界面的微观组织结构,发现硬质合金覆层内部组织结构致密,覆层与钢基体之间形成了具有一定厚度的过渡层。

Using Mo powder, Fe-B alloy powder and Fe powder as raw materials, added with WC, Cr3C2, TiC and C, Cr, Ni, multiple hard alloy cladding materials were prepared on Q235 steel substrate to enhance the wear resistance and corrosion resistance by vacuum liquid phase sintering technology. The mechanical properties of cladding materials, including bending strength and hardness were tested. It is shown that the hardness of CW cladding materials is HRA84.8 and it is 2.3 times harder than Q235 steel substrate ; the bending strength of CW cladding materials is 1175. 52 MPa and it is 1.4 times higher than Q235 steel substrate; when carbide hard phase is added into cladding, the cladding materials possess higher bending strength and hardness than simplex Mo2FeB2 hard alloy cladding materials. The microstructure and element distribution in the vicinity of claddings and the bond interface were investigated by SEM. The structure inside of the cladding was compact. No clear bonding interface existed between cladding and steel substrate, but a transitional layer with a certain thickness was formed.