Ni-Al粉末直流TIG电弧堆焊层的稀释率及其控制

为了控制直流TIG电弧粉末堆焊层的稀释率,获得Ni、Al含量较高的涂层,本文研究了堆焊规范对堆焊层的形状、稀释率和化学成分的影响规律,并从降低母材温度的角度出发,考察了辅助冷源对堆焊层稀释率的影响.结果表明,随着堆焊规范的减弱,堆焊层的熔宽和熔深减小、堆高增加,堆焊层的稀释率由70%降低到32%,有利于获得低稀释率的堆焊层.在本文试验条件下采用辅助冷源对母材进行冷却,使堆焊层的堆高增大、熔深减小、稀释率降低到21%.

Dilution Rate and Its Control in DC TIG Arc Ni-Al Powder Surfacing

To aim at controlling the dilution rate and obtaining surfacing bead rich in Ni and Al, the effects of the surfacing parameters on the geometric parameters, dilution rate and composition of bead were investigated. In view of decreasing the temperature of the base metal, the effects of the assistant cooler on the dilution rate were studied. The results show that with lowering the surfacing parameters, the width and penetration of bead decrease, the reinforcement increases,and the dilution rate drops from 70% to 32% ,which is in favor of obtaining low dilution rate surfacing layer. With assistant cooler used in the surfacing process on selected operation condition, the reinforcement of bead increases, the penetration decreases,and the dilution rate decreases to 21%.