电磁搅拌对堆焊层金属组织及性能的影响

Effect of electromagnetic stirring on microstructure and properties of surfacing metal

对低碳钢表面进行等离子弧堆焊时外加间歇交变纵向磁场,研究了电磁搅拌对堆焊层金属组织及性能的影响,并利用光学金相、X射线衍射、显微硬度和湿砂橡胶轮磨损试验等手段对试样进行测试分析。研究发现,随着磁场参数的增强,堆焊层中硬质相的数目随之增加,且均匀分布于堆焊层的表面,堆焊层金属的耐磨性也随之增强;当磁场电流为3 A,磁场频率为10 Hz时,堆焊层金属的性能达到最佳状态。结果表明,在适当的电磁参数作用下,堆焊层金属才能获得最佳的细化效果;而且电磁搅拌可以控制堆焊层表面中硬质相的形态,使其由长条状和六方块状的混合形态逐渐转变为较规则、均匀的六方块状,从而进一步提高堆焊层金属的硬度和耐磨性。

The effect of electromagnetic stirring on the microstructure and properties of surfacing metal during the applied longitudinal intermittent alternative magnetic field on low carbon steel with plasma arc surfacing are investigated and discussed.The surfacing metal was analyzed using optical metallography,X-ray diffraction,microhardness testing and wet sand rubber wheel abrasion testing.It's found that the hard phases are increasing and distributing homogeneously in the surface of surfacing layer with changing magnetic parameters and the wear resistance of surfacing metal is increasing gradually.The optimal result is acquired when the magnetic parameters are 3 A,10 Hz.The experimental results indicate that the optimal effect of grain refining can be gained with the proper magnetic parameters and electromagnetic stirring can control the morphology of hard phase in surfacing metal.The morphology of hard phases with strip and hexagon distribution without magnetic field are shifted to only hexagon alignment distribution with proper magnetic field,which it can improve the hardness and wear resistance of surfacing metal greatly.