TA18钛合金TIG焊接头组织及耐腐蚀性能研究
Study on Microstructure and Corrosion Resistance of TA18 Titanium Alloy TIG Welding Joint
郭纪龙 1付娟 1赵勇 1刘新 2潘艳飞 2陈夫刚1
作者信息
- 1. 江苏科技大学 先进焊接技术省级重点实验室,江苏 镇江 212003
- 2. 江苏长江智能制造研究院,江苏 常州 213164
- 折叠
摘要
采用2B实芯焊丝对 12 mm厚的TA18 钛合金板进行了TIG焊试验,研究了TA18 钛合金TIG焊接头的显微组织,不同腐蚀介质中的电化学和应力腐蚀行为.结果表明:TA18 钛合金接头焊缝区域分布大量粗大的柱状晶和少量等轴晶,在盖面、打底及中间填充层存在部分网篮组织;热影响区主要由针状的α'(α'')相、残余α相和β相组成.在 3.5%NaCl溶液中进行电化学腐蚀试验,TA18 钛合金接头各区域的耐腐蚀性能从高到低为:母材＞焊缝＞热影响区.比较TA18 钛合金接头在大气环境和模拟海水环境中的慢应变速率拉伸应力-应变曲线,表明该接头的力学性能受海水影响不明显,且对海水的应力腐蚀敏感性较低.
Abstract
TIG welding test of 12 mm thick TA18 titanium alloy plate was carried out by using 2B solid core welding wire.The microstructure,the electrochemical and stress corrosion behavior in different corrosive media of the TA18 titanium alloy TIG welding joint were studied.The results show that a large number of coarse columnar crystals and a small amount of equiaxed crystals are distributed in the TA18 titanium alloy joint's weld area,part of net basket organization exsits in the cover,bottom and intermediate filler layers.The microstructure of the heat-affected zone is mainly composed of needle-like α'(α'')phase,residual α phase and β phase.When the electrochemical corrosion test is carried out in 3.5%NaCl solution,the corrosion resistance of each region of the TA18 titanium alloy joint from high to low is as follows:base metal,weld,heat-affected zone.Comparing the slow strian rate tensile stress-strain curves of the TA18 titanium alloy joint in air and simulated sea water,the mechanical properties of the joint are not significantly affected by seawater and it has low stress corrosion sensitivity to seawater.
关键词
TA18钛合金/TIG焊/电化学腐蚀/应力腐蚀Key words
TC18 titanium alloy/TIG welding/electrochemical corrosion/stress corrosion引用本文复制引用
基金项目
国家自然科学基金(51901087)
江苏省自然科学基金(BK20190975)
出版年
2024
NETL
NSTL
万方数据