(1. 南京航空航天大學(xué) 高新技術(shù)研究院 仿生結(jié)構(gòu)及材料防護(hù)研究所，南京 210016；
2. 南京航空航天大學(xué) 材料科學(xué)與技術(shù)學(xué)院，南京 210016)
摘 要: 在2A12鋁合金表面通過微弧氧化制備氧化鋁陶瓷膜。用X射線衍射儀分析薄膜的相構(gòu)成，用渦流測厚儀測量膜層的厚度，用自動轉(zhuǎn)塔顯微硬度計測量薄膜的顯微硬度，利用微摩擦磨損試驗機研究Al2O3薄膜/Si3N4球在干摩擦及水潤滑下的摩擦磨損特性，用非接觸表面三維形貌儀測量薄膜的磨損體積，并采用掃描電鏡觀察磨痕的表面形貌。結(jié)果表明：2A12鋁合金微弧氧化陶瓷膜主要由α-Al2O3相和γ-Al2O3相組成；干摩擦?xí)r，薄膜主要發(fā)生磨粒磨損和疲勞磨損，摩擦因數(shù)隨法向載荷和滑行速度的增大分別從0.79和0.82增加到0.87，磨損率則分別從4.07×10−5mm3/(N∙m)和4.36×10−5mm3/(N∙m)增加到9.69×10−5mm3/(N∙m)；水潤滑時，薄膜主要發(fā)生摩擦化學(xué)磨損和疲勞磨損，摩擦因數(shù)隨法向載荷和滑行速度的增大分別從0.69和0.67下降到0.65，磨損率則分別從3.84×10−5mm3/(N∙m)和2.89×10−5mm3/(N∙m)增加到4.47×10−5mm3/(N∙m)；薄膜在干摩擦?xí)r的摩擦因數(shù)和磨損率都大于相同實驗參數(shù)下水潤滑時的摩擦因數(shù)和磨損率，表明水介質(zhì)有效地改善了體系的摩擦條件，降低了薄膜的磨損。
關(guān)鍵字: 鋁合金；微弧氧化；潤滑；摩擦；磨損
（1. Institute of Bio-inspired Structure and Surface Engineering, Academy of Frontier Science, Nanjing University of Aeronautics and Astronautics,Nanjing 210016, China;
2. School of Materials Science and Engineering,Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China）
Abstract:The alumina ceramic coating was prepared by micro-arc oxidation (MAO) technique on 2A12 Al alloy. The phase structure of Al2O3 coating was analyzed by X-ray diffractometry, its thickness was measured using MINITEST1100 equipment, and its micro-hardness was determined using micro-hardness equipment. The friction and wear properties of Al2O3 coatings sliding against silicon nitride ceramic ball were carried out under dry and water-lubricated conditions using tribo-meters. The wear volume of Al2O3 coatings was measured using non-contact surface profilometer, and the worn surface of Al2O3 coatings was observed by scanning electron microscopy (SEM). The results show that the alumina ceramic coating on 2A12 Al alloy is mainly composed of α-Al2O3 and γ-Al2O3 phase. Under dry condition, the wear mechanism of Al2O3 coatings is mainly abrasive wear and fatigue wear. With an increase in normal load and sliding speed, the friction coefficient of Al2O3 coatings increases from 0.79 and 0.82 to 0.87, and the specific wear rate of Al2O3 coatings increases from 4.07×10−5mm3/(N∙m) and 4.36×10−5mm3/(N∙m) to 9.69×10−5 mm3/(N∙m), respectively. Under water-lubricated condition, the wear mechanism of Al2O3 coatings is mainly tribo-chemical wear and fatigue wear. With an increase in normal load and sliding speed, the friction coefficient of Al2O3 coatings decreases from 0.69 and 0.67 to 0.65, respectively, and the specific wear rate of Al2O3 coatings increases from 3.84×10−5mm3/(N∙m) and 2.89×10−5mm3/(N∙m) to 4.47×10−5mm3/(N∙m), respectively. Moreover, the friction coefficient and specific wear rate of Al2O3 coatings under dry condition are lower than those under water-lubricated condition, which indicates that water-lubrication availably improves the friction condition and decreases the wear loss of Al2O3 coatings.
Key words: Al alloy; micro-arc oxidation; lubrication; friction; wear
