占空比对铝合金微弧氧化膜层的摩擦性能影响  

Effect of Anode Duty Ratio on Friction and Wear Characteristics of Ceramic Film Produced on Aluminum Alloy by Micro-Arc Oxidation

作　　者：文帅 李小晶 张敏[1] 

机构地区：[1]辽宁师范大学物理与电子技术学院,辽宁 大连

出　　处：《应用物理》2021年第2期108-118,共11页Applied Physics

摘　　要：采用微弧氧化技术在2A50铝合金表面原位生成耐磨的高硬度微弧氧化膜层,考察正向占空比对2A50铝合金表面陶瓷层的影响规律。利用扫描电子电镜、X射线衍射仪表征微弧氧化膜层的微观形貌、物相组成,利用显微硬度计测试微弧氧化膜层的硬度,并通过摩擦磨损试验机与轮廓仪评价膜层的耐磨性。结果表明:陶瓷层主要成分为α-Al2O3与γ-Al2O3;当正向占空比小于25%时,随占空比的增加,不稳定的γ-Al2O3逐渐转变为稳定的α-Al2O3,陶瓷层结构逐渐致密。当占空比大于25%时,陶瓷层的致密性与结晶度降低;在占空比为25%时,陶瓷层的硬度最大(约1107 HV0.5),磨损率较低(约2.67 ×10−10 cm3 (N∙m)−1),磨痕表面轮廓规整且浅,综合耐磨性最佳。Hard and wear-resistant ceramic coatings were prepared on the surface of 2A50 aluminum alloy using micro-arc oxidation (MAO) technique to investigate the effect of the anode duty cycle on the ceramic coating. The microstructure and phase composition of the MAO ceramic coatings were characterized by scanning electron microscopy and X-ray diffractometry. The hardness of the coat-ings was tested by microhardness tester, and the wear resistance was evaluated by friction and wear tester. The results show that the main components of the ceramic coatings are α-Al2O3 and γ-Al2O3. When the anode duty ratio is less than 25%, the unstable γ-Al2O3 gradually changes into stable α-Al2O3 with the increase of duty ratio, and the ceramic coatings become gradually denser. When the duty cycle is more than 25%, the compactness and crystallinity of the ceramic coatings decrease;when the duty cycle is 25%, the hardness of the ceramic coatings is the highest (about 1107 HV0.5), the wear rate is low (about 2.67 ×10−10 cm3 (N∙m)−1), the worn track is regular and shallow, and the comprehensive wear resistance is the best.

关 键 词：微弧氧化 铝合金 摩擦磨损 占空比 

分 类 号：TG1[金属学及工艺—金属学]