粗糙表面弹塑性加卸载多级接触模型

真实工程表面在微观尺度上都是粗糙的,它们之间的接触实际上是表面微凸体的接触,粗糙表面间的接触行为对接触部件的真实承载能力、摩擦磨损等性能都有重要影响,研究工程表面间的真实接触行为是摩擦学研究的主要内容之一。采用最小均方误差法得到表面轮廓抛物线拟合曲线,在最大限度近似原始表面轮廓的同时,该方法能够更好地适用于微凸体弹塑性接触加卸载模型。通过单个微凸体上的支承载荷将总体级别模型和微凸体级别模型相联系,建立粗糙表面多级接触加卸载模型。以柱面与平面接触为算例,将接触区域视为与圆柱母线平行的离散线条集合,得到微凸体法向变形量和粗糙表面真实接触面积,该模型可用于分析粗糙表面弹塑性加卸载的真实接触行为。

Multilevel Contact Model of Elastic-Plastic Loading and Unloading on Rough Surfaces

Real engineering surfaces are rough at microscopic level and the contact between two rough surfaces is actually the asperities contact. The contact behavior of rough surfaces plays a vital role for the real carrying capacity, friction and wear of contact parts. The research of the real contact behavior between engineering surfaces is one of tribological main contents. Parabolic approximation curves of the rough profile obtained by the least mean squares approach can perferably approximate original surface profile preferably. Meanwhile, it can be suitable for asperity contact loading and unloading model better. By means of single asperity supporting load, the global is connected with the asperity level model, and a multilevel contact model of rough surfaces is established. Taking contact between the cylinder and flat surface for instance, the contact zone is treated as a summation of discrete lines paralleled to the cylindrical generatrix, and asperity interference and real contact area of the rough surfaces are obtained. This model is suitable for researching real contact behavior of elasticplastic loading and unloading between rough surfaces.