TC4盘件双面辗压的实验研究

Experimental study on double-sided roll forming of TC4 disk

对TC4盘件进行高温双面辗压成形实验研究,观察了辗压后盘件的形状变化和微观组织分布。实验确认TC4盘件热辗压与铅盘室温辗压具有类似的形状变化特征,呈现出盘件直径增大、辗压槽两侧厚度增加、辗压槽出现"甩高"现象等。辗压后盘件微观组织分析结果表明,温度和变形对盘件微观组织变化有显著影响,因此盘件不同部位微观组织有明显差别:盘外缘温度偏高,变形量较小,组织处于相区;盘中心温度偏低,变形量较小,组织处于α+β相区;辗压槽及附近区域温度基本均匀为930℃,组织上处于β区,该区内材料变形差别较大,槽表面变形比槽中心大得多,组织上表现为初生α组织减少,并且槽表面比槽中心有更多的初生α组织转变为β相。

An experimental study on hot double-sided roll forming of TC4 titanium alloy disk was presented. The shape change and microstructure distribution of the deformed disk were observed in the forming experiment. It is found out that the shape change character of the TC4 disk hot rolled is similar to that of the lead disk coldly rolled. The main shape changes include a disk diameter increase, a local thickness increase near groove positions, and the “shuaigao” phenomena. It is also found out that the temperature and the deformation have significant effect on the microstucture of disk, so there is obvious difference in microstructure evolution in different positions of the disk. For example, in the disk fringe, the microstructure state is in β phase region due to high temperature and small strain; in the region near the disk center, the microstructure state is in α＋β phase region due to lower temperature and small strain; in the transition region, the microstructure state is in α＋β phase region due to middle temperature （930 ℃） and large strain, the deformation in groove surface is much bigger than that in groove center, the α phase decreases and there is more α phase in groove surface translated into β phase than that in groove center.