X65/316L与AISI4130/Inconel625复合管焊接接头力学性能及腐蚀行为研究

采用ERNiCrMo-3焊丝成功焊接X65/316L与AISI4130/Inconel625复合管，研究了复合管焊接接头的力学性能和腐蚀行为。采用拉伸试验、全焊缝拉伸试验、冲击试验、硬度测试表征了焊接接头的力学性能。参照ASTM G39和ASTM G5的相应标准对复合管焊接接头进行了CO2应力腐蚀和电化学腐蚀性能测试。结果表明，复合管焊接接头的抗拉强度达到583 MPa，断裂发生在X65/316L母材处；焊缝屈服强度为441.4 MPa，抗拉强度为725.9 MPa，延伸率达到37.67%；在-10 ℃试验条件下，焊缝的冲击吸收功为157 J，接头硬度值呈现梯度过渡。复合管焊接试样经过CO2应力腐蚀试验后失重达标，在母材和焊缝处没有观察到裂纹；电化学腐蚀试验后焊缝和热影响区的耐蚀性与母材相当。

Research on Mechanical Properties and Corrosion Behavior of Welded Joints of X65/316L and AISI4130/Inconel625 Clad Pipe

X65/316L and AISI4130/Inconel625 clad pipe were successfully welded with ERNiCrMo-3 filler metal, and the mechanical properties and corrosion behavior of the welded joints were studied in this paper. Tensile test, all-weld metal tensile test, impact test, as well as hardness test were performed to characterize the mechanical properties of the joints. The CO2 stress corrosion test and electrochemical corrosion test were conducted on clad pipe joints according to the corresponding standards of ASTM G39 and ASTM G5. The results showed that tensile strength of the joint achieved 583 MPa and crack propagated along X65/316L base metal; however, the yield strength, tensile strength and elongation of the weld metal reached to 441.4 MPa, 725.9 MPa, 37.67%, respectively. The absorbed impact energy of the weld metal at-10℃was 157 J, and the hardness value of joint presented gradient transition. After CO2 stress corrosion test, the weightlessness of clad pipe welded sample reached the standard, and no crack was observed in base metal and weld; the corrosion resistance of weld and HAZ is was equal to that of base metal after electrochemical corrosion test.