曲轴修复中的堆焊工艺研究

Research on Surfacing Technology in Crankshaft Repair

为提高曲轴的耐磨性,用WSE-350交直流脉冲氩弧焊机在20CrMnTi上用SHQ-605耐磨焊丝进行了堆焊工艺参数的研究,研究堆焊过程中焊接电流和氩气流量对堆焊层性能和组织的影响。用HV-1000显微硬度仪测试堆焊层的显微硬度为2291~3549HV;用M DW-02磨损试验机测试堆焊层磨损率为2×10^-7~7.33×10^-7g/N·min,摩擦系数为0.2~0.8;用SEM分析堆焊层显微组织,堆焊层与20CrMnTi熔合良好,金相组织主要为板条状马氏体。结果表明,当氩气流量为8L/min,焊接电流为50A时,此时堆焊层显微硬度为2837HV,摩擦系数为0.27,磨损率2×10^-7g/N·min,堆焊层的耐磨性较好。

In order to improve the wear resistance of the crankshaft,the WSE-350 AC-DC pulsed argon arc welding machine was used to study the surfacing process parameters of SHQ-605 wear-resistant welding wire on 20 CrMnTi.The effects of welding current and argon flow rate on the performance and microstructure of the welding layer were studied.The microhardness of the welding layer was measured by HV-1000 microhardness meter from 2291 HV to 3549 HV.The wear resistance of the welding layer was tested by MDW-02 reciprocating friction and wear tester.Wear rate is 2×10^-7~7.33×10^-7 g/N·min,the friction coefficient is 0.2~0.8.The microstructure of the welding layer was analyzed by SEM,and the welding layer was well fused with the 20CrMnTi substrate.Metallographic structure is mainly lath martensite.The results show that when the welding current is 50 A and the argon flow rate is 8 L/min,the microhardness of the welding layer is 2837HV,the friction coefficient is 0.27,wear rate is 2×10^-7 g/N·min,and the wear resistance of the surfacing layer is better.