目的 研究海洋大气环境与拉伸疲劳载荷耦合作用对30CrMnSiNi2A钢腐蚀损伤行为的影响。方法 在湿热海洋大气环境万宁试验站户外环境，首次采用海洋大气环境-拉、压、弯载荷耦合试验设备对30CrMnSiNi2A钢开展海洋大气环境-拉伸疲劳载荷耦合试验，利用金相显微镜、耦合试验设备和扫描电镜，探讨海洋大气环境腐蚀与拉伸疲劳载荷耦合作用对30CrMnSiNi2A钢的腐蚀形貌、腐蚀产物、拉伸性能及断口形貌的影响。结果 30CrMnSiNi2A钢静态暴露试验和耦合试验的腐蚀特征均为点蚀，静态暴露试验1 a和耦合试验35 d的最大腐蚀深度分别为95 μm和54 μm。静态暴露试验1 a，30CrMnSiNi2A钢的抗拉强度、屈服强度和断后伸长率分别下降6.6%、6.5%、31.0%;耦合试验35 d，30CrMnSiNi2A钢的抗拉强度、屈服强度和断后伸长率分别下降11.0%、11.4%、34.5%。断口形貌结果显示，30CrMnSiNi2A钢耦合试验的裂纹源附近扩展区为准解理形貌，存在细小二次裂纹，裂纹以疲劳源为中心，向芯部不断扩展，形成了具有方向性的腐蚀疲劳损伤。结论 海洋大气环境腐蚀与拉伸疲劳载荷的耦合作用可以加速30CrMnSiNi2A钢拉伸性能的下降，与静态暴露试验相比，耦合试验的加速倍率约为静态暴露试验的10倍。

This work aims to study the effect of the coupling action between the marine atmospheric environment and tensile fatigue load on the corrosion damage behavior of 30CrMnSiNi2A steel. The test environment was the humid and hot marine atmospheric environment of the Wanning test site in Hainan. The coupling test of marine atmospheric environment and tensile fatigue load for 30CrMnSiNi2A steel was carried out for the first time with the coupling test equipment of marine atmospheric environment and tension, compression and bending loads. The effects of the coupling action of marine atmospheric corrosion and tensile fatigue load on corrosion morphology, corrosion products, tensile properties and fracture morphology of 30CrMnSiNi2A steel were studied by metallographic microscope, coupling test equipment and environmental scanning electron microscope. The corrosion characteristics of 30CrMnSiNi2A steel in the static exposure test and the coupling test were pitting corrosion. The maximum corrosion depth of the static exposure test for 1 year and the coupling test for 35 days were 95 μm and 54 μm respectively. In the static exposure test for 1 year, the tensile strength, proof strength plastic extension and percentage elongation after fracture of 30CrMnSiNi2A Steel decreased by 6.6%, 6.5% and 31.0% respectively; in the coupling test for 35 days, the tensile strength, proof strength plastic extension and percentage elongation after fracture of 30CrMnSiNi2A Steel decreased by 11.0%, 11.4% and 34.5% respectively. The results of fracture morphology showed that the extending zone near the crack source in the coupling test of 30CrMnSiNi2A Steel was quasi cleavage morphology, and there were small secondary cracks. The cracks of 30CrMnSiNi2A steel in the coupling test extended from the fatigue source to the core, forming directional corrosion fatigue damage. The results showed that the descending rate of tensile properties of 30CrMnSiNi2A steel was accelerated by the coupling action of marine atmospheric corrosion and tensile-compressive fatigue load. And the acceleration ratio of the coupling test was about 10 times that of the static exposure test.