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试验采用了插销ＳＣＣ试验法，测定了四种管线钢及其焊缝在混合硝酸盐介质中的ＳＣＣ临界值（临界断裂应力σｉｍｐＳＣＣ和临界断裂功ＷＡＳＣＣ），并采用动电位快慢扫描技术，结合侧面金相观察及扫描断口分析，讨论了其ＳＣＣ的行为。结果表明，所研究材料在硝盐介质中具有较高的ＳＣＣ抗力。其中母材的ＳＣＣ抗力最佳，均超过母材抗拉强度σｂ的６０％，而相应的焊缝已接近４０％σｂ，所有应力腐蚀裂纹均沿固态相变组织的晶界扩展，断口呈典型的沿晶破裂。
The SCC test method was adopted to determine the SCC critical values (critical stress σimpSCC and critical breaking work WASCC) of four kinds of pipeline steel and its weld in mixed nitrate media. The kinematic potentiodynamic scanning was used in combination with the lateral Metallographic observation and scanning fracture analysis, discussed the behavior of its SCC. The results show that the materials studied have higher SCC resistance in nitrate media. Among them, the SCC resistance of the base metal is the best, both exceeding 60% of the tensile strength σb of the base metal, and the corresponding weld is close to 40% σb. All the stress corrosion cracking propagates along the grain boundaries of the solid phase transformation structure, The crack along the crystal.