Soft variable polarity plasma arc horizontal welding technology and weld asymmetry
Soft variable polarity plasma arc horizontal welding technology and weld asymmetry
复制标题
软变极性等离子弧水平焊接技术及焊缝不对称
DOI：
10.1179/1362171815y.0000000006
复制
发表时间：
2015-05-01
影响因子：
3.3
通讯作者：
Fan, C. L.
中科院分区：
文献类型：
--
作者：
Zhang, Q. L.;Yang, C. L.;Fan, C. L.
针对铝合金水平位置焊接存在的问题，提出了软变极性等离子弧焊接技术。与普通变极性等离子弧相比，等离子弧的电弧温度场形状、电弧压力分布和熔池特性等对小孔稳定性有重要影响。应用中的稳定性可用操作窗口来评价。焊接热循环曲线、焊缝显微组织和显微硬度表明，水平焊缝存在不对称性。研究了不对称性和焊接缺陷对拉伸强度和断裂行为的影响。熔池中小孔周围流体流动的不对称性是造成这种不对称性的根本原因。
Soft variable polarity plasma arc welding technology has been proposed to solve the problems in horizontal position welding for aluminium alloys. Arc thermal field shape, arc pressure distribution and the characteristic of the weld pool, which are important for keyhole stability, have been changed compared with the ordinary variable polarity plasma arc. Its stability in application can be evaluated by the operational window. The thermal cycle curves, microstructures and microhardness of the horizontal position weld indicate the weld asymmetry. The influence of asymmetry as well as welding defects on tensile strength and fracture behaviour has been studied. The fundamental reason for the asymmetry was considered as the asymmetric fluid flow around the keyhole in the weld pool.