- 學位論文
以田口實驗設計製備Cu-BTA奈米複合顆粒為潤滑添加劑之磨潤特性研究
Study on tribological properties of preparation of Cu-BTA composite nanoparticles as lubricant additives by Taguchi experimental design
摘要
本論文目的為以田口實驗設計製備Cu-BTA奈米複合顆粒，為潤滑添加劑之磨潤特性研究。在本研究中，BTA水溶液與CuCl2水溶液反應生成實驗反應物，藉由反應物熱分解過程合成Cu-BTA奈米複合顆粒。BTA作為Cu奈米顆粒合成過程之穩定劑，及抑制Cu奈米顆粒在不同濃度中氧化，所以此過程，並不需要額外惰性氣體保護Cu奈米顆粒氧化。此外，以田口法標準直交表分配實驗參數，以觀察溶液溫度、溶液pH值和BTA劑量，對合成Cu-BTA奈米複合顆粒平均粒徑上之影響。以UV-Vis光譜儀、FT-IR、XRD、TG-DTA和TEM分析Cu-BTA奈米複合顆粒物質特性。然後，使用UV-Via光譜儀對Cu-BTA奈米複合顆粒作為添加劑之懸浮性進行評估，使用與ASTM G99標準相符之pin-on-disk儀器在相同測試條件下，研究Cu-BTA奈米複合顆粒作為添加劑之磨潤特性。磨潤試驗完成後對上下試片磨耗表面進行觀測，包含表面元素和磨耗表面形貌，以及對摩擦係數、磨疤直徑和表面粗糙度差異進行分析。歸納Cu-BTA奈米複合顆粒在磨潤實驗過程中之運作機制。結果顯示在最佳劑量比例與合成條件下，合成之Cu-BTA奈米複合顆粒平均粒徑約為7.91nm圓形球狀顆粒。Cu-BTA奈米複合顆粒分散於石蠟基礎油中可以大大提升潤滑油之磨潤性能，摩擦係數與磨疤直徑在跟石蠟基礎油相比分別減少40.7%和40.0%。磨潤機制是沉積膜於接觸區域形成，避免摩擦表面直接接觸以及減少接觸表面間之摩擦力，以及Cu-BTA奈米複合顆粒之球型形狀可以在摩擦表面起滾珠作用。
並列摘要
This aim of this paper was to study tribological properties of the synthesis of Cu-BTA composite nanoparticles as lubricant additives by Taguchi experimental design. In this study, the Cu-BTA composite nanoparticles were synthesized bya thermal decomposition process using experimental reactant, which were made by reacting CuCl2 aqueous solution with BTA aqueous solution. BTA functions as a stabilizer of the Cu nanoparticles and inhibition of oxidation of Cu nanoparticles in various concentrations so that this process does not need extra inert gases to protect the oxidation of Cu nanoparticles. Additionally, effects of solution temperature, pH value of solution, and dosage of BTA on the mean diameter of synthesized Cu-BTA composite nanoparticles was observed by orthogonal array for arranging parameters of experiment through Taguchi method. The material properties of Cu-BTA composite nanoparticle was anlysised by UV-Vis absorption spectrum, FT-IR, XRD, TG-DTA and TEM. Afterwards, the suspension ability of Cu-BTA composite nanoparticle as lubricant additives was evaluated by UV-Vis absorption spectrum. Tribological properties of Cu-BTA composite nanoparticles as lubricant additives were investigated by pin-on-disk apparatus according to ASTM G99 standard under the same testing conditions. After tribological experiments were finished, the worn surface of up-and-down specimens was observed through surface elements and appearance of worn surface. The differences of friction coefficient, wear scar diameter, and surface roughness was anlyzed. The result of tribological experiments was explicable in terms of wear scar diameter, friction coefficient, and the morphology of worn surface. The possible mechanisms of Cu-BTA composite nanoparticles in process of triobological experiments were generalized. Results show that the mean diameter of synthesized Cu-BTA composite nanoparticles is about 7.91nm spherical shape particle in the best percentage of dosage and synthesis condition. The tribological performance of lubricating oils can be improved significantly by dispersing Cu-BTA composite nanoparticles in liquid paraffin oil. The friction coefficient and the wear scar diameter have been reduced by 40.7% and 40.0% respectively compared with liquid paraffin oil. In conclusion, the significant finding show that the tribological mechanism is that a deposit film in the contacting regions was formed, which prevented the direct contact of rubbed surfaces and greatly reduced the friction force between contacting surface. Besides, the spherical shape of Cu-BTA composite nanoparticles functioned as rolling ball between the rubbed surfaces.