Ti6Al4V合金在海水中用作紧固件和热交换器时，会遭受腐蚀与微动磨损的耦合损伤。将电化学工作站与微动磨损测试装置集成，于海水环境中对Ti6Al4V合金的电化学行为与摩擦磨损性能测试，结合微观形貌及结构表征等研究手段，探究了Ti6Al4V合金不同外加载荷（10N、20N、30N、40N、50N）下的微动腐蚀磨损性能与损伤机理。结果表明：随载荷增加，Ti6Al4V合金的材料损失率从10N时的102.30 mm/y增大至50N时的114.20 mm/y。腐蚀电位随载荷增加向阴极方向移动，腐蚀电流密度增大3个数量级。材料的磨损机制表现为塑性变形、粘着磨损、磨粒磨损和剥层磨损的复合特征。值得注意的是，机械磨损分量W0从10N时的39.86 mm/y显著上升至50N时的105.30 mm/y，增加了164%。由于高载荷下机械磨损对点蚀的抑制作用，协同作用分量S则从62.11 mm/y大幅降低至8.57 mm/y。因此，低载荷条件下微动腐蚀磨损主要由腐蚀加速磨损主导，而高载荷条件下则主要源于机械磨损作用。微观层面上，磨痕内的点蚀程度随着载荷增加减轻而裂纹扩展加剧。同时，Ti6Al4V合金磨痕的亚表面形成了典型的亚表层梯度微观结构，且晶粒细化程度随载荷增大而增加。

When used as fasteners and heat exchangers in seawater, Ti6Al4V alloy suffers from coupled damage of corrosion and fretting wear. By integrating an electrochemical workstation with a fretting wear testing device, the electrochemical behavior and tribological performance of Ti6Al4V alloy in seawater were investigated. Through microscopic morphology and structural characterization, the fretting corrosion wear properties and damage mechanisms under different external loads (10N、20N、30N、40N、50N) were explored. The results show that with increasing load, the material loss rate of Ti6Al4V alloy rises from 102.30 mm/y at 10 N to 114.20 mm/y at 50 N. The corrosion potential shifts cathodically with increasing load, while the corrosion current density increases by three orders of magnitude. The wear mechanism exhibits composite characteristics including plastic deformation, adhesive wear, abrasive wear, and delamination wear. Notably, the mechanical wear component W? increases significantly from 39.86 mm/y at 10 N to 105.30 mm/y at 50 N, representing a 164% rise. Due to the inhibitory effect of mechanical wear on pitting under high loads, the synergistic component S decreases substantially from 62.11 mm/y to 8.57 mm/y. Thus, under low loads, fretting corrosion wear is primarily dominated by corrosion-accelerated wear, whereas under high loads, mechanical wear plays the major role. At the microscopic level, the severity of pitting within the wear scar diminishes with increasing load, while crack propagation intensifies. Additionally, a typical subsurface gradient microstructure forms beneath the wear scar of Ti6Al4V alloy, with the degree of grain refinement increasing as the load rises.

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