隨著科技的進步，磨潤行為對於機械工業的重要性與日俱增，因此有許多研究者在進行鍍層磨潤學的研究，鍍層磨潤學發展至今，已經可以藉由使用耐磨耗性更佳的鍍層來改善機械元件的損耗與破壞與使用耐熱性或是耐腐蝕性佳的鍍層來增加機械元件的應用性，而對於鍍層與基材接合性不好的問題，則可透過多層鍍層或是功能梯度鍍層的方式來解決，而隨著橫向等向性鍍層的應用日漸增加，進行彈液動潤滑條件下的橫向等向性功能梯度鍍層表現有其必要性。
本研究建立剛球與橫向等向性功能梯度鍍層的彈液動潤滑模型，使用有限元素法來處理流-固耦合問題，統御方程式包含了雷諾方程式、線性彈性方程式與負載平衡方程式，研究中假設鍍層的楊氏模數隨著厚度方向冪次變化，探討在彈液動潤滑情況下，非均質常數與橫向等向性獨立變數對於橫向等向性功能梯度鍍層的影響，分析流體壓力與液膜厚度分佈變化、鍍層厚度方向應力變化。
從分析結果得知，當橫向等向性功能梯度鍍層的x,y方向楊氏模數Ep與鍍層z方向的楊氏模數Ez的非均質常數皆為5時，可將鍍層厚度方向的最大von Mises應力降為最低，此結果與等向性功能梯度鍍層的趨勢一致；在固定橫向等向性功能梯度鍍層的楊氏模數下，可以藉由改變鍍層的蒲松比與剪切模數來降低流體的中心壓力與膜厚。

For conventional coating, the stress may be concentrated at the interface between the coated film and the substrate, which can lead to the failure or debonding of the coated film, this phenomena can be eliminated by using the functionally graded material coating, because it decrease the mismatch of material properties at the interface between the coated film and the substrate by change the constitute of the material gradually. In this paper, the behaviors of the transversely isotropic functionally graded coating in elastohydrodynamic lubrication (EHL) condition are analysed by using finite element method to solve modified Reynolds equation, elasticity deformation equation and load balance equation simultaneously. The film pressure distribution, film thickness distribution, and von Mises stress distribution under operating condition in EHL regimes are discussed. As a result, it is shown that the material inhomogeneity parameter has an important effect on the elastic deformation and stresses in the plate, by decreasing the Poisson’s ratio or shear modulus can lead to the increase of the film thickness.

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