本研究提出適用於乳化液的混合物潤滑模型，並應用於冷軋之部分潤滑分析。冷軋成形分為進口區、加工及出口，並考慮輥輪與薄板彈性變形之影響。在輥輪高轉速的情況下，吸附在輥輪與薄板表面之吸附油層會被中間的乳化液層分離，在輥輪與薄板間產生含上下吸附油層及中間乳化液層的混合油膜，在低轉速時，輥輪與薄板表面之吸附油層則會合併。假設輥輪與薄板皆為光滑表面且施加前向張力情況下，聯立求解雷諾氏與薄板塑性方程式，結果發現使用純油為潤滑劑時，轉速低於0.3 m/s時在出口區之薄板和滾輪會產生接觸；當使用油相濃度5%之乳化液為潤滑劑時，則轉速低於10 m/s時便會產生接觸，一般而言，其臨界接觸轉速隨上升而增加。
當考慮薄板表面具有峰端及凹口時，發現薄板所承受之壓力(ps)與油膜所承受之壓力(pf)並不同，若薄板在加工區有峰端，會使油膜壓力大幅上升，但薄板壓力則小幅增加；若薄板在加工區有凹口，則會導致在凹口區域無法形成油膜壓力，但薄板壓力則變化較不顯著。
當乳化液的壓力黏度係數和輥輪轉速增加，則油膜厚度會變厚，接觸長度則因油膜變厚而變短。薄板縮減比愈大及前向張力愈小則會增加接觸長度。當薄板於出口接觸區因彈性回復而出現峰端時，會大幅增加其接觸壓力，使出口區再度產生塑性變形，但是凹口處因油膜陡升則無法產生接觸壓力。

A mixture lubrication model suitable for emulsions has been developed in the partial lubrication analysis of cold rolling. The rolling section is divided into the inlet, work and outlet zones, where the elastic deformations of the rolls and the strip are considered. At the high rolling speed, the two adsorbed layers on the surfaces of the rolls and strip are separated by the emulsion layer, but they merge to form a continuous oil film at the low rolling speed. In this study, the modified Reynolds and Von Karman equations are simultaneously derived and solved by the Newton-Raphson method for the smooth surfaces of the rolls and the strip. Results show that roller and the strip come into contact with each other at the outlet zone for the roll speed lower than 0.3 m/s using pure oil and 10 m/s using emulsion with 5% oil concentration. In general, the critical speed to cause this contact increases along with reduction ratio).
Considering the asperity and the dent on the strip surface at work zone, the pressure (pf) generated by hydrodynamic film is different from that (ps) on the surface of strip. The pressure (pf) significantly increases with the height of asperity, but ps increases slightly. If the strip has dents, the pressure (pf) decreases quickly, but ps changes a little.
The film thickness of the emulsion increases along with the pressure-viscosity coefficient and the roll speed, but the contact length decreases because the film thickness increases. With increasing reduction ratio or decreasing front tension, the contact length increases. Considering the elastic recovery on the contact zone, the contact pressure significantly increases along with the height of asperity, so that the plastic deformation may occur, but it cannot generate the contact pressure in the dent area.

審定書 i
誌謝 ii
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 ix
符號說明 x
第一章 緒論 1
1.1 研究動機 1
1.2 乳化液概述 1
1.3 文獻回顧 2
1.3.1 乳化液之彈液動油膜實驗觀察 2
1.3.2 乳化液之彈液動潤滑理論分析 4
1.3.3 乳化液之彈塑液動潤滑理論分析 5
1.3.4 彈液動及彈塑液動之部份潤滑理論分析 5
1.4 論文架構 6
第二章 理論模型 9
2.1純油 9
2.1.1進口區油膜與板厚方程式 9
2.1.2進口區雷諾方程式 11
2.1.3進口區邊界條件 11
2.1.4加工區油膜與板厚方程式 11
2.1.5加工區雷諾方程式 12
2.1.6加工區塑性方程式 12
2.1.7加工區邊界條件 13
2.1.8出口區油膜與板厚方程式 13
2.1.9出口區雷諾方程式 14
2.1.10出口區邊界條件 14
2.1.11黏度方程式 15
2.2乳化液 15
2.2.1進口區雷諾方程 17
2.2.2加工區雷諾方程 18
2.2.3出口區雷諾方程 20
2.3 薄板之微觀幾何 21
第三章 數值分析 26
3.1純油 26
3.1.1進口區 27
3.1.2加工區 28
3.1.3出口區 31
3.2乳化液 32
3.2.1進口區 32
3.2.2加工區 33
3.2.3出口區 36
第四章 結果與討論 40
4.1光滑表面之壓力及油膜分布 40
4.2不同薄板表面特徵於加工區之影響 41
4.3不同前向張力對部分潤滑之影響 42
4.4不同薄板材料對部分潤滑之影響 43
4.5薄板彈性回復使峰端出現之影響 44
第五章 結論與未來展望 69
5.1結論 69
5.1未來展望 70
參考文獻 71

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