异种材质等离子弧粉末堆焊界面

Analysis on aluminum bronze plasma powder surfacing interface

为了有效提高铝青铜堆焊层在钢表面的力学性能,并为研究铜合金异种材质堆焊工艺参数的合理制订提供参考。本文采用反极性弱等离子弧,将铝青铜合金粉末堆焊到20g母材上。通过金相显微、扫描电镜(SEM)、线扫描方法对堆焊层界面附近元素扩散的规律进行研究。研究表明,当堆焊电流为110 A时,其组织为致密的α-Cu和网状结构的(α+γ2),此时具有较好组织结构。随着堆焊电流的增大,热输入的增加,界面附近发生的"泛铁"现象随之加剧。当堆焊电流过大时,界面熔合区产生渗透裂纹。其产生主要是由于堆焊过程中的焊接应力、毛细管效应和冷却过程中形成低熔点共晶体三方面共同作用。

To improve the mechanical properties of aluminum bronze surfacing on steel effectively,and to provide reference for formulating reasonable processing parameters on the study of dissimilar metal surfacing of copper alloy,aluminum bronze alloy surfacing weld were formed on 20g by using reverse polarity weak plasma arc method in the article.The laws of elements' diffusion around surfacing weld layer had been studied by means of optical metallograghy,SEM and line-scanning.Research showed that the organization took on the compact structure of α-Cu and the net structure of(α+γ2)when surfacing at the current of 110 A.The experiment results showed that the 'extensive iron' was increased obviously with the increase of welding current and heat input.When surfacing at the excessive current,penetrating crack would turn up on the fusion zone around the interface.The penetrating crack mainly due to three parts of the interaction that welding stress in the surfacing process,capillary effects and low melting point eutectic material formed in the process of cooling.