衝擊彈液動潤滑(impact-EHL)對於相互碰撞物體的壽命與性能分析至關重要，其應用範疇廣泛，除衝壓模具、齒輪、凸輪外，亦可進一步涵蓋表面硬化(珠擊)處理之衝擊行為研究，這些情境皆存在局部瞬間的法向衝擊。然而，傳統彈性液動潤滑理論缺乏對更實際情況的考量，例如同時考慮基材塑性硬化行為、流體之流變行為及邊界滑移效應等。因此，有必要將上述影響一併納入考量，以更精確地預測衝擊潤滑行為及其對相互接觸物體動態響應的影響。
為解決上述挑戰，本研究同時建立修正暫態雷諾方程式(涵蓋奈維爾滑移邊界與流變效應)、潤滑油膜厚度方程式、剛性球運動方程式，並結合基材彈塑性變形理論，以更全面分析衝擊塑彈液動潤滑問題(impact-PEHL)。分析結果顯示，傳統 impact-EHL 模型往往高估油膜的中心壓力、最小油膜厚度及衝擊負載，卻低估中心油膜厚度及最小油膜厚度發生位置。
研究結果更進一步指出，滑移長度增加或流動指數降低導致中心膜厚減小，主因在於潤滑油流動性提高、剪切阻力降低所致。而對於剪切增稠流體(n>1, shear thickening fluid)，滑移效應會削弱增稠行為，使油膜厚度趨近於無滑移牛頓流體之結果。由於衝擊過程中系統需維持力平衡狀態，滑移效應對整體壓力分佈的影響相對有限。此外，隨著流動指數的增加，中心壓力與油膜厚度均會增加，剛球的回彈速度與衝擊負載峰值則會下降；而當基材之切線模數增加時，回彈速度與衝擊負載將會提升，同時塑性應變與永久變形量則會減小。

Impact plasto-elastohydrodynamic lubrication (impact-PEHL) is vital for predicting the durability and performance of components like stamping dies, gears, cams, and surface treatments such as shot peening, all of which involve localized impacts. Conventional elastohydrodynamic lubrication (EHL) models often neglect substrate plasticity, fluid rheology, and boundary slip, leading to unrealistic predictions. Consequently, the present study develops a novel model by coupling a modified transient Reynolds equation—incorporating Navier slip boundary conditions and non-Newtonian rheology—with the motion equation of a rigid ball and substrate plastic deformation theories, including both elastic-perfectly plastic and linear hardening models. It is found that traditional impact-EHL models tend to overestimate the central pressure, impact load, and minimum film thickness while underestimating the central film thickness and the location of minimum film thickness. By contrast, the proposed impact-PEHL model provides predictions that are more consistent with actual impact-lubricated contact behavior. Parametric analysis indicates that increased slip length or a lower flow index reduces central film thickness by enhancing lubricant mobility. For shear-thickening fluids (n>1), slip weakens their thickening effects, causing the lubricant behavior to approach that of a Newtonian fluid. While slip has a minimal effect on overall pressure due to force balance, it significantly influences local substrate deformation. Furthermore, a higher flow index leads to increased central pressure and film thickness but results in lower rebound speed and a reduced maximum impact load. Conversely, a greater tangential modulus of the substrate enhances rebound velocity and impact load while simultaneously reducing the magnitude of plastic strain and permanent deformation.

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