DZ125合金表面Cr-Al-Y涂层抗高温氧化性能及摩擦性能  

High Temperature Oxidation Resistance and Friction Properties of Cr-Al-Y Coating on DZ125 Alloy

作　　者：田兴达 李涌泉 王存喜 梁国栋 TIAN Xing-da;LI Yong-quan;WANG Cun-xi;LIANG Guo-dong(School of Material Science&Engineering,North Minzu University,Yinchuan 750021,China;College of Mechatronic Engineering,North Minzu University,Yinchuan 750021,China)

机构地区：[1]北方民族大学材料科学与工程学院,银川750021 [2]北方民族大学机电工程学院,银川750021

出　　处：《表面技术》2023年第9期170-177,共8页Surface Technology

基　　金：国家自然科学基金(51961003,52161009);宁夏自然科学基金(2020AAC02025)。

摘　　要：目的提高DZ125合金的抗高温氧化性能和耐磨性。方法采用包埋渗技术在DZ125合金表面制备Cr-Al-Y涂层,分析Cr-Al-Y涂层经高温氧化后的组织结构和相组成,对比研究涂层与基体的摩擦行为。结果Cr-Al-Y涂层具有多层组织结构,经高温氧化100 h后,涂层的平均质量损失量仅为0.85 mg/cm^(2)。由于在高温氧化过程中Cr-Al-Y涂层形成了连续致密的Al_(2)O_(3)和Cr_(2)O_(3)氧化膜,随着氧化温度的升高,涂层表面的氧化速率增大,导致氧化产物剥落,并出现表面缺陷。Cr-Al-Y涂层的摩擦因数明显低于DZ125基体的摩擦因数,DZ125合金的摩擦因数约为0.45,Cr-Al-Y涂层的摩擦因数约为0.2。在摩擦过程中,DZ125合金发生了犁削磨损和磨粒磨损,涂层表面发生了磨粒磨损。结论该涂层具有优异的抗高温氧化性能,连续致密的Al_(2)O_(3)氧化膜和Cr_(2)O_(3)氧化膜能够有效阻挡氧化性气氛与基体直接接触,从而降低氧化速率。Cr-Al-Y涂层的摩擦因数明显低于DZ125基体的摩擦因数,在磨损过程中涂层表面的氧化膜能有效阻挡GGr15球与基体发生直接接触式对磨,并且形成的Al_(2)O_(3)和Cr_(2)O_(3)起到了润滑相的作用,从而减小了摩擦因数,降低了磨损率,提高了合金的耐磨性。In order to improve the high temperature oxidation resistance and wear resistance of DZ125 alloy,Cr-Al-Y coating was prepared on the surface of DZ125 alloy by pack cementation technology.The microstructure and phase composition of Cr-Al-Y coating after high temperature oxidation were analyzed and the friction behavior between the coating and the substrate was compared.The results showed that the prepared Cr-Al-Y coating had a multi-layer structure.The Cr-Al-Y coating of DZ125 prepared by embedding infiltration at 1050℃for 2 h had a multilayer structure.The outer layer was composed of Ni_(3)Cr_(2)and Al_(2)O_(3),the middle layer was composed of Ni_(3)Cr_(2)and a small amount of Ni3Al,and the inner layer was composed of Ni3Al and the average weight loss of the coating was only 0.85 mg/cm2 after 100 hours of high temperature oxidation.During the high temperature oxidation process,the Cr-Al-Y coating formed continuous and dense Al_(2)O_(3)and Cr_(2)O_(3)oxide films.The Al element in the coating was accelerating outward diffusion,forming a new oxide film,and then repairing the oxide film.This process intensified the oxidation rate of the coating surface.With the increase of oxidation temperature,the oxidation rate of the coating surface intensified,resulting in the peeling of oxidation products and surface defects.The friction coefficient of Cr-Al-Y coating was obviously lower than that of DZ125 substrate.The friction coefficient of DZ125 alloy was about 0.45.The friction coefficient of Cr-Al-Y coating was about 0.2.The friction coefficient increased gradually with the wear time.After 15 minutes of wear,the friction coefficient of the coating tended to be stable,and the friction coefficient was about 0.25.Ploughing wear and abrasive wear occurred on DZ125 alloy during the friction process,while abrasive wear occurred on the coating surface.The high temperature oxidation kinetic curve of Cr-Al-Y coating showed a law of weight increase firstly and weight loss later.Cr-Al-Y coating showed a stable oxidation rate.The co

关 键 词：DZ125合金 Cr-Al-Y涂层 高温氧化 氧化膜 耐磨性 磨损率 

分 类 号：TG174[金属学及工艺—金属表面处理]