• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2016, Vol. 52 ›› Issue (2): 26-32.doi: 10.3901/JME.2016.02.026

• 高速高效熔化焊接工艺专栏 • 上一篇    下一篇


齐铂金,  杨舟,  杨明轩,  从保强   

  1. 北京航空航天大学机械工程及自动化学院  北京  100191
  • 收稿日期:2015-04-20 修回日期:2015-08-14 出版日期:2016-01-15 发布日期:2016-01-15
  • 作者简介:齐铂金,男,1963年出生,博士,教授,博士研究生导师。主要研究方向为高频脉冲焊接电源及控制。 E-mail:qbj@buaa.edu.cn
  • 基金资助:

Analysis on Characteristic of Ultra High Frequency Pulsed Gas Tungsten Arc Welding Process

QI Bojin,  YANG Zhou,  YANG Mingxuan,  CONG Baoqiang   

  1. School of Mechanical Engineering & Automation, Beihang University, Beijing 100191
  • Received:2015-04-20 Revised:2015-08-14 Online:2016-01-15 Published:2016-01-15

摘要: 基于5 mm厚的Ti-6Al-4V钛合金平板,分别采用常规钨极氩弧焊(Conventional gas tungsten arc welding, C-GTAW)和超高频脉冲钨极氩弧焊(Ultra high frequency pulsed GTAW, UHFP-GTAW)工艺,选用相同平均电流(60 A)进行焊接,同时利用FLUKE Ti400红外热像仪对熔池中心温度进行实时监测,分别对电弧定点燃烧时、以50 mm/min焊速移动时采集的熔池中心温度进行分析。由测量结果可知,与相同条件下C-GTAW相比,UHFP-GTAW作用下的熔池中心温度最大值增加了10~40 K,表明该工艺具有更高的能量密度。分析1.5 mm钛合金对接工艺试验的组织性能测试结果发现,焊缝区细小均匀的针状α'马氏体形成的网篮组织含量增加,热影响区组织α'相呈现短且小的针状且排列更为致密,可改善接头的拉伸力学性能、疲劳性能。UHFP-GTAW焊缝的伸长率最小增幅为30%,断面收缩率最小增幅为50%,疲劳寿命至少增加2倍。

关键词: Ti-6Al-4V钛合金, 超高频脉冲GTAW, 红外测温, 组织性能

Abstract: Bead-on-plate welding test are carried on 5 mm thickness Ti-6Al-4V titanium alloy plates by the processes both of conventional gas tungsten arc welding (C-GTAW) and the ultra high frequency pulsed GTAW (UHFP-GTAW) in the same average welding current (60 A). The temperature of molten pool center is monitored in real time with thermal infrared imager Fluke Ti400. These measurements before the arc moving and moving at a speed of 50 mm/min are analyzed respectively. The results show that compared with the C-GTAW in same condition, the maximum of the temperature of weld pool center are 10-40 K enhanced by UHFP-GTAW for higher density power with different pulse frequencies. The microstructure and mechanical properties tests are conducted on 1.5 mm thickness Ti-6Al-4V butt joints, verified that the UHFP-GTAW had influences in improving tensile and fatigue properties because of a larger density of basketweave formed by the short and uniform acicular α' martensite in fusion zone and a more compact arrangement of α' in heat affected zone. The elongation and percentage reduction of area respectively are increased by 30% and 50% at least, and the fatigue life triples at least.

Key words: infrared temperature measurement, microstructure and properties, Ti-6Al-4V titanium alloy, ultra high frequency pulsed GTAW