近年來在工業的快速發展下，元件在性能的需求上愈加嚴苛，經由表面鍍膜的處理除了改善元件的磨潤特性外，亦能增進其機械性能。在機械元件的使用中，經常會加入潤滑油來避免兩表面間的直接接觸，而如今鍍膜的使用日益廣泛，因此有更進一步探討鍍膜特性對彈液動潤滑影響的需要。
本研究針對剛球擠壓一披覆彈性薄膜的彈性基材系統，探討定負載下兩者在相對擠壓時之彈液動特性，使用有限元素法耦合雷諾方程式、負載平衡方程式及線性彈性方程式，在分析在擠壓過程時流體之暫態壓力、油膜形狀、彈性變形外，並進一步分析材料內部von Mises應力的變化。
經模擬結果得知，當鍍膜材料楊氏模數愈大，壓力分佈值愈大，接觸半徑愈小，內部應力值亦會上升。對於硬質鍍膜，隨著鍍膜厚度的增加，最大中心壓力值上升、最小膜厚下降至一漸進值，在軟質鍍膜時則會有相反的趨勢。在應力分析的部分，硬且厚的鍍膜會產生較大的應力，在變形回復時，最大應力位置將開始下降並靠近鍍膜/基材界面處，而隨著鍍膜厚度增加，最大應力位置將發生於鍍膜內部，減少基材降伏的機會。透過本篇的分析結果，將可作為日後相關領域在設計時能夠參考的依據。

A rigid sphere approaching a lubricated flat surface with an elastic coating and an elastic substrate is explored under constant load conditions. The FEM with the Newton-Raphon iteration method is used to solve the transient modified Reynolds equation, the elasticity deformation equation, load balance equation, and pressure-dependent relations of viscosity and density of lubricant simultaneously. The transient pressure profiles, film shapes, elastic deformation during the pure squeeze process under various operating conditions in the EHL regime are discussed. The simulation results reveal that the greater the elastic modulus of the coating is, the greater the pressure distribution is. The central film thickness decreases(increases) as the Ec increases before(in) the deformation recovery stage. These characteristics are important for the lubrication design of the mechanical element with coating.

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