CaCO3对复合粉粒和实心焊丝明弧堆焊高铬合金组织及耐磨性的影响

目的 将活性剂引入复合粉粒,旨在改变电弧对其的作用属性,以提高堆焊金属的合金化元素量,从而改善其耐磨性。方法 以复合粉粒和实心焊丝作为填充材料,采用自保护明弧焊法制备系列高铬合金。借助X射线衍射仪、扫描电镜及附属电子能谱仪等手段,研究复合粉粒添加CaCO₃含量对其堆焊高铬合金的组织及耐磨性的影响。结果 随着CaCO₃添加量增大,焊缝的碗形熔深随之消除,堆焊合金的粉粒填充量由43.7%提高到47.5%,熔合比由0.281降低至0.140。这使堆焊合金组织由亚共晶变为过共晶结构,初生M₇C₃相的体积分数随之明显增加,堆焊合金硬度从55.4HRC提高至62.3HRC,磨损质量损失从54.9mg降低至16.7mg,耐磨性净增加2.3倍,合金磨损方式包括微观切削和显微剥落。高速摄影仪所拍电弧影像和电流电压数据显示,复合粉粒添加CaCO₃粉,使其堆焊电弧形态从圆锥形转变变为扁平钟罩形,电弧覆盖面积扩展约2倍。结论 复合粉粒引入CaCO₃粉,促使电弧扩展,这不仅提高了复...

Effects of CaCO3 on the Microstructure and Abrasion Resistance of High Chromium Alloys Deposited by Open Arc Welding with Composite Powder Particles and Solid Wire

The work aims to introduce activating flux into the composite powder particles (CPPs) to change the arc behavior on CPPs and increase the content of alloying elements in hardfacing metals, so as to improve their abrasion resistance. Five groups of high chromium alloys were deposited by self-shielded open arc welding with filler materials such as CPPs and H08A solid wire. Then, the effects of different CaCO3 contents on the arc shape, arc stability, microstructure, and abrasion resistance of high-chromium hardfacing alloys were investigated in detail.