稀土镧对硼铁激光熔覆层耐磨性能影响

研究了镧对硼铁激光熔覆改性层的组织和摩擦学性能的影响。对不同La含量的熔覆层进行了摩擦磨损实 验,实验结果表明:含适量La熔覆层的耐磨性得到很大提高。在本实验条件下,La的加入量最佳值约为2%,此时 熔覆层磨损量较未加La时减少25.8%,当La加入量过多时,熔覆层耐磨性反而降低,甚至低于不加La时的耐磨 性。扫描电子显微镜显示含适量La的改性层的硼铁化合物组织明显细化且弥散分布于铸态组织中,磨斑表面硼元 素(1s电子轨道)的XPS图谱分析表明熔覆层中铁与硼主要以Fe2B相存在。

Effect of Rare Earth Elements Lanthanum on Wear Resistance of Laser Clad Fe-B-Si Composite Coatings

The wear resistance of laser cladding Fe-B layer containing lanthanum(La) on steel 45 substrate was studied, and the influence of La on microstructure was analyzed. Laser cladding experiment was performed using Fe, B 4 C and FeSiRE powders. Wear tests were done for cladding layer containing different rate of RE La. The results show that the wear resistance of cladding layer containing a certain amount of La is remarkably improved, it declines distinctly when the content of La exceed the ideal amount, and even worse than the wear resistance of the cladding layer that does not contain La. The wear resistance is excellent and it is improved by 25.8% on condition that the content of La reach about 2%. It is showed that Fe-B phase structure of the cladding layer containing a certain amount of La is remarkably refined through scanning electron microscope (SEM).Based on boron element(1 s orbit) X-ray photoelectron microscopy(XPS) analysis of abrasion surface, the conclusion can be made that the basic content is Fe 2 B phase rather than FeB phase.