Abstract: The 2.25Cr1Mo steel that was frequently used in petrochemical equipment was welded by hot welding process at 750 ℃ and 850 ℃. The welding residual stress of every welded specimen was measured by the small blindhole method. The electrochemical workstation was used to measure the stress corrosion property of every welded specimen in alkaline, acidic and neutral medium. The microstructure of welded joint was analyzed by metallographic technique. The results showed the hot welding process could obviously reduce the welding residual stress of 2.25Cr1Mo steel welded plate and raise the stress corrosion property of it in every medium. In addition, the higher the process temperature was, the bigger the reduced degree of welding residual stress was, the more the stress corrosion property was improved. At 850 ℃, the welding residual stress was reduced by the degree of above 60% and the stress anticorrosion property was raised by the degree of above 30%. The microstructure of welded joint was improved after high temperature welding. The mechanical property was maintained.

Key words: Hot welding process, Welding residual stress, Stress corrosion, Metallographic analysis, Blindhole method

摘要： 针对石化设备常用材料2. 2 5 C r 1Mo钢, 分别在7 5 0℃和8 5 0℃的工艺温度下利用热焊工艺方法对其
进行焊接, 采用盲孔法测定了各焊接试件的焊接残余应力, 利用电化学工作站分别测量了焊接试板在碱性、 酸性和
中性腐蚀介质中的腐蚀速率, 通过金相分析了焊缝区显微组织变化。结果表明, 热焊工艺降低了2. 2 5 C r 1Mo钢焊件
的焊接残余应力, 提高了其在各种介质中的抗应力腐蚀性能; 随着工艺温度的升高, 焊接残余应力下降幅度增大, 抗
应力腐蚀性能提升显著; 在8 5 0℃的工艺温度下, 焊接残余拉应力降低6 0%以上, 抗应力腐蚀性能提升3 0%以上。
同时, 焊接后焊缝区显微组织得到改善, 力学性能得到保证。

关键词: 热焊工艺, 焊接残余应力, 应力腐蚀, 金相分析, 盲孔法