Dual motion fretting wear behaviors of titanium and its alloy in artificial saliva

纯钛和钛合金在人工唾液中的复合微动磨损行为(英文)

A dual motion combined by radial and tangential fretting was achieved on a modified hydraulic fretting wear test rig. The dual motion fretting tests of medical pure titanium （TA2） and Ti6Al7Nb alloy in artificial saliva were carried out under varied contact inclined angles （45° and 60°）, and the maximum imposed load varied from 200 to 400 N at a constant loading speed of 6 mm/min. The effects of the cyclic vertical force and the inclined angle were investigated in detail. Dynamic analysis in combination with microscopic examinations shows that the wear scar and plastic deformation accumulation present a strong asymmetry. The Ti6Al7Nb has better wear resistance than TA2 in artificial saliva at the same test parameters, and with the increase of inclined angle and decrease of imposed load, the wear reduces accordingly. The wear mechanisms of pure titanium TA2 and Ti6Al7Nb alloy under the condition of dual motion fretting in artificial saliva are abrasive wear, oxidative wear and delamination.

在改进后的液压伺服双向微动磨损试验机上实现双向微动。在人工唾液环境中，对TA2纯钛和Ti6Al7Nb合金在6 mm/min的加载速度下以不同接触倾角（45°和60°）和不同最大外加载荷（200-400 N）条件下进行复合微动磨损实验。详细研究循环垂向力和倾斜角的影响。结合动力学分析与微观检测结果显示：磨痕和塑性变形累积呈现强烈的非对称性。在人工唾液环境中和相同实验参数下，Ti6Al7Nb合金比TA2纯钛具有更好的抗磨损性能，并随着倾斜角度的增加和外加载荷的降低，磨损相应减轻。TA2纯钛和Ti6Al7Nb合金在人工唾液环境中的复合微动磨损机制是磨粒磨损、氧化磨损和剥层。