TC4钛合金超音频直流脉冲TIG焊

摘要

Firstly, the traits about ultra-sonic pulse TIG welding technology had been introduced in this paper. The disciplinarian of peak current and pulse frequency influence to arc welding plasmas flow force had been analyzed especially. Several TC4 titanium alloy workpieces had been welded by ultra-sonic pulse TIG welding and conventional direct current TIG welding technology respectively. In order to detect blowhole faults in these weld beads, X-radial check-up had been introduced. By these detection results, several of process mechanisms to make blows overflow fleetly, which aroused by the ultra-sonic pulse TIG welding, had been analyzed. These welding joints without faults had been made tensile properties detection samples. A series of tensile properties data had been obtained.By means of scanning electron microscope, the relationship between microstructure and these strength performances had been studied.In comparison with conventional direct current TIG welding technology, blowhole faults has been reduced by introducing 60kHz and 80kHz ultra-sonic pulse TIG welding technology. It also shows that welding joints specific elongation is improved obviously with the pulse current frequency being increased.%首先对超音频直流脉冲TIG焊的特点进行了介绍,重点分析了的峰值电流、脉冲频率等关键工艺参数对超音频直流脉冲TIG焊电弧轴向等离子流力的影响规律.采用频率不同的几组超音频直流脉冲TIG焊工艺及常规直流TIG焊工艺分别焊接了2.5mm厚的TC4钛合金.用X-射线探伤检测焊缝中的气孔缺陷,根据检测结果,分析了超音频直流脉冲TIG焊过程中,能够加速气泡逸出熔池的几种作用机制;对于无缺陷的接头,检测了接头的拉伸力学性能,观察了拉伸断口SEM照片.结果表明:在脉冲频率60kHz,80kHz时,超音频直流脉冲TIG焊工艺能使TC4钛合金焊缝中的气孔缺陷出现的几率减少;随着脉冲电流频率提高,焊接接头的断后延伸率得到了显著提高.