TC4钛合金轮圈热旋成形技术研究

Hot spinning technology of wheel rim of TC4 titanium alloy

针对TC4钛合金轮圈的结构特点,设计了钛合金轮圈热旋的模具结构,研究了TC4钛合金的热变形特性,分析了钛合金热旋翻边过程成形缺陷的产生原因,最终获得了钛合金轮圈的合理热旋工艺.研究表明,采用分瓣组合模具是成形钛合金车轮合理的模具结构方案,热旋工艺参数对钛合金轮圈的成形质量有显著的影响.TC4钛合金轮圈的适宜翻边温度为600～700℃,采用略小于坯料壁厚的间隙（小于坯料壁厚的10%左右）及较小的进给比（f≈0.1 mm/r）可有效防止翻边起皱和开裂.直边较短的轮圈采用直线轨迹可一道次翻边成形.

The die device for wheel rim was designed according to the structural characteristic of wheel rim of TC4 titanium alloy,hot deformation behavior was investigated by tensile experiment,and the causes of forming defects during hot spinning were analyzed,based on which the proper process scheme of hot spinning for wheel rim was obtained.The results show that split die device is a feasible scheme of die structure for hot forming of wheel rim,and the flange quality is directly influenced by spinning temperature,roller gap,feed ratio,etc.The reasonable spinning temperature of TC4 titanium alloy should be selected in the range of 600～700 ℃,the flange gap should be about 10 percent smaller than wall thickness of sheet blank and the feed ratio should be low at about 0.1 mm/r,by which wrinkling and cracking of the flange part could be avoid effectively.One-pass hot spinning by linear trajectory could be adopted to form wheel rim of titanium alloy with small length of flange.