Sr、Mg及热处理对Al-Si铝合金焊丝堆焊层耐磨性的影响

Effects of Strontium, Magnesium and Heat Treatment on the Wear Resistance of Surfacing Layer of Al-Si Aluminum Welding Wires

摘要:

为了提高4043铝合金焊丝堆焊层的耐磨性，在传统4043铝合金焊丝成分基础上，添加Mg与变质剂Sr，对Al-Si-Mg-Sr合金焊丝焊后堆焊层进行热处理，研究了Mg、Sr以及热处理工艺对焊丝焊后堆焊层耐磨性的影响。结果表明，在4043铝合金焊丝中添加变质剂Sr可以改变堆焊层组织中共晶硅颗粒的形态；Mg可以为堆焊组织增加强化相Mg2Si；合理的热处理工艺可以球化共晶硅颗粒，增强共晶硅颗粒与基体的结合能力；三者的共同作用可以显著提高焊丝堆焊层的耐磨性。

Abstract:

In order to improve the wear resistance of surfacing layer of 4043 aluminum welding wires, Mg and Sr were added based on the chemical composition of traditional 4043 aluminum welding wires and the surfacing layer from obtained Al-Si-Mg-Sr welding wires were heat treated. The effects of Mg, Sr and heat treatment on the wear resistance of the surfacing layer were studied. The results show that the morphology of eutectic silicon particles could be changed by Sr and the strengthening phase Mg2Si appears with the addition of Mg. Meanwhile eutectic silicon particles are spheroidized and their binding ability with the matrix is intensified after the reasonable heat treatment. Therefore, Sr, Mg and heat treatment improve significantly the wear resistance of the surfacing layer together.