某采煤机重载齿轮磨损表面激光熔覆及磨损性能研究

Research of the Laser Cladding and Wear-resistance of Worn Surface of Heavy Load Gear of Mining Machine

以齿面磨损失效的德国进口久益(JOY)采煤机行走齿轮为绿色再制造研究对象,通过对其表层受损疲劳层去除、优化再制造激光参数以完成无裂纹无孔隙的耐磨耐腐蚀激光复合层制备。继而检测激光复合熔覆层与基体结合状态、并对熔覆层抗磨损性能等做了系统分析。研究中所采用的绿色再制造方案选用高效率、与基体结合区平整的矩形光斑激光熔覆模式结合镍基自熔合金粉末进行再制造工艺研究。通过对磨损失效轮齿表面依次做除锈除渣、去疲劳点蚀、无损探伤、激光增材制造,再对激光熔覆层样品做纵剖面扫面电镜(SEM)分析、磨损测试,最终得出结论:矩形激光束制备的再制造齿面抗磨损性能优异、激光熔覆层与轮齿基体呈现优良冶金结合,故而再制造轮齿工作面质量已达到并超过新品齿面,符合绿色再制造产品标准。

Taking the worn out tooth surface of walking gear in JOY mining machine which imported from Germany as green re-manufacture study object,the anti-wear and anti-corrosion coating without crack nor pore is successfully produced by two techniques of fatigue layer removal and laser cladding in which parameters are optimized. The bonding state of laser clad coating and substrate interface is test,the wear-resistance of clad coating is systematically analyzed. The green re-manufacturing scheme in this study adopted high efficiency,rectangular spot laser technology combined with nickel based self-fluxing alloy produced comparatively flatter coating/substrate interface to conduct the study of re-manufacturing process. The slag and rust as well as fatigue spotting layer are completely removed from failure gear flank followed by laser incremental manufacturing and then the SEM analysis of the cross-section of laser cladding layer,wear resistance test is carried out. Finally a conclusion can be drawn,the re-manufacturing tooth surface produced by rectangular spot laser cladding has excellent wear resistance property,there is a high quality metallurgical bonding formed between laser cladding layer and the substrate gear,thus the work surface of gear has reached and surpassed the new product and properly matched the green re-manufacturing standard.