镍基718材料表面修饰类型的有限元仿真优化设计

目的研究不同凹坑形状组合分布对表面特性的影响规律,进一步提高微造型表面的摩擦学性能和承载能力。方法利用有限元仿真技术和单因素仿真设计,分析比较半球形、方形、三角形三种凹坑形状混合分布的微造型表面,对镍基718高温合金摩擦学性能的影响。结果分析获得了不同速度和载荷下,不同微造型表面对油膜承载力和摩擦系数的影响规律。半球形、方形、三角形三种凹坑形状共同存在的微造型表面的承载能力最好,而半球形凹坑和方形凹坑组合分布的微造型表面的摩擦系数最小。结论对镍基718高温合金材料进行表面凹坑修饰,可以显著提高油膜的承载能力,有利于完整润滑油膜的形成。不同凹坑形状的组合分布对材料摩擦学性能和承载能力的影响非常大,随着速度和载荷的增大,各微造型表面的摩擦系数差别减小,凹坑形状及组合分布对摩擦学性能的影响减弱。

Simulation Optimization Design of Surface Finish Types for Inconel 718 Alloy in Finite Element Method

The work aims to further improve tribological properties and carrying capacity of micro-textured surface, and study the law of effects of different dimples combined distribution on surface properties. Finite element simulation technology and single factor design were used to analyze and compare effects of micro-textured surface textured with all hemispheric dimples, square dimples and triangle dimples on tribological properties of Inconel 718 alloy. Law of the effects of different micro-textured surfaces on bearing capacity and friction coefficient of oil film was analyzed and obtained. The micro-textured surface textured with all three dimple shapes exhibited the best bearing capacity. And the micro-textured surface with hemispheric dimples and square dimples had the minimum friction coefficient. For the Inconel 718 high-temperature alloy surface textured with modified dimples, the bearing capacity of oil film can be improved significantly, which is beneficial to the formation of complete oil film. Combined distribution of different dimple shapes has great significance on tribological properties and bearing capacity of material. Moreover, the gap among friction coefficients of different micro-textured surfaces narrows as the velocity and load increase, which implies that dimple shapes and combined distribution have weaker effects on tribological properties.