间歇交变磁场对Fe_5堆焊合金组织性能的影响

Influence of longitudinal intermittent alternative magnetic field on microstructures and properties of Fe_5 surfacing alloy

为了研究外加磁场对堆焊组织性能的影响,在采用等离子弧堆焊铁基合金粉末时加入纵向间歇交变磁场,利用纵向间歇交变磁场控制焊缝熔池中金属液体的流动,改变结晶过程中的热传导及溶质的分配,细化堆焊层金属的组织,并控制堆焊层中硬质相的形态及分布.通过对堆焊层进行硬度、磨损实验以及显微组织分析,得出了间歇交变磁场强度对堆焊层金属硬度和耐磨性的影响规律.实验结果表明,施加磁场比未施加磁场的堆焊层硬度高,耐磨性好;间歇交变磁场电流I=3A时,堆焊层的性能最佳.

In order to determine the influence of imposed mangetic field on both microstructured and properties of surfacing alloy, the longitudinal intermittent alternative magnetic field was applied during plasma arc surfacing of the Fe-based alloy powder. The appication of the longitudinal intermittent alternative magnetic field can control the fluxion of metal liquid in the welding pool, change the heat transference and solute distribution in the solidification process, and control the morphology and distribution of hard phase in the surfacing deposit. The influence of the longitudinal intermittent alternative magnetic field intensity on the hardness and wear resistance of the surfacing deposit was obtained through performing the hardness and wear tests as well as the microstrnctural observation. The results show that the surfacing deposit with introducing the magnetic field has higher hardness and better wear resistance than one without introducing the magnetic field. The performance of the surfacing deposit is optimal when the longitudinal intermittent alternative magnetic field current equals to 3 A.