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采用微区相电化学测试技术，测量和研究了１６Ｍｎ钢焊接接头上不同热经历区在硝酸盐溶液中的微区相电化学行为（包括自腐蚀电位、自腐蚀电流密度和极化曲线）以及外加载荷（应力）的影响．此外，还分别测量了各区中铁素体和珠光体的电化学行为，尤其是加载状态下的行为．结果表明，加载后各热经历区以及各区中铁素体和珠光体的自腐蚀电位均比未加载前负移，相应的自腐蚀电流密度增大，铁素体和珠光体之间电位差明显减小．加载后各热经历区中自腐蚀电位最负和次负的仍处在熔合线区和不完全正火区，从而成为焊接接头腐蚀电池中的率先腐蚀区．应力促进腐蚀并非是通过增大铁素体和珠光体之间的电位差，而是通过提高各微区相组织自身的电化学活性来实现的．
The micro-phase electrochemical behaviors of 16Mn steel welded joints in nitrate solution were measured and studied by using the micro-zone phase electrochemical test (including self-corrosion potential, self-corrosion current density and polarization curves) and Influence of applied load (stress). In addition, the electrochemical behavior of ferrite and pearlite in each zone was also measured separately, especially at loading. The results show that the self-corrosion potentials of ferrite and pearlite in each of the heat-experienced regions and regions are higher than those before loading, and the corresponding self-corrosion current density is increased. The potential difference between ferrite and pearlite is significantly reduced small. After loading, the most negative and negative negative self-corrosion potentials in each heat-experienced zone are still in the fusion zone and incompletely normalized zone, which becomes the first corrosion zone in the welded joint corrosion cell. Stress-induced corrosion is not achieved by increasing the potential difference between ferrite and pearlite, but by increasing the electrochemical activity of the individual microstructure itself.