金属薄板等离子电弧加热弯曲成形实验

为了研究金属薄板等离子电弧加热弯曲成形的规律及机理,采用等离子电孤沿直线来回对1Cr18Ni9Ti和Q235薄板进行加热弯曲成形实验.结果表明,随着等离子电弧在薄板上扫描次数的增加,其弯曲角度近似呈线性增大;在一定范围内热输入越大(如减小扫描速度、减小电弧长度、增加电弧电流等),板材厚度越小,薄板的弯曲角度越大;在较低的热输入下等离子电弧加热弯曲成形使晶粒细化,有利于改善薄板受热区域显微组织的机械性能;成形过程中存在残余应变强化,受热区域硬度提高;等离子电弧加热弯曲成形还可以降低机械加工引起的残余应力,有效减少回弹.

The Experimental Study on Flexible Forming of Sheet Metal Using Plasma Arc

In order to study the laws and mechanisms of plasma arc forming,an experimental investigation was performed with 1Cr18Ni9Ti and Q235 sheet metals scanned forward and backward by moving it with respect to the stationary plasma arc.The experimental results show that the bending angle caused by plasma arc scanning is approximately in proportion to the scanning times;with the heat input increasing and the thickness of sheet metal decreasing the bending angle is sharply increased under the same scanning times.While the heat input is low,the grain in heating area is refined,and its mechanical performance is improved;with the increasing of the heat input,the residual strain-hardening in the heating area becomes reinforced,which causes the micro hardness to be increased.The plasma arc forming can also decrease the residual stresses caused in the mechanical processes,which can be of great significance in preventing rebounding.