Effects of slurry pack cementation temperature on microstructure and wear resistance of Ti-Al co-deposited coating on copper plated nickel layer  

包渗温度对Ti-Al渗层组织和耐磨性能的影响(英文)

作　　者：王红星[1] 张炎[1] 杨少锋[1] 柳秉毅[1] 

机构地区：[1]南京工程学院材料工程学院,南京211167

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第2期449-454,共6页中国有色金属学报（英文版）

基　　金：Projects(YKJ201203,CKJB201205)supported by the Nanjing Institute of Technology,China

摘　　要：In order to improve the wear resistance properties of copper substrate, a layer of electroplated nickel was firstly deposited on copper substrate, subsequently these electroplated specimens were treated by slurry pack cementation process with a slurry pack cementation mixture composed of TiO2 as titanizing source, pure Al powder as aluminzing source and also a reducer for titanizing, an activator of NH4Cl and albumen （egg white） as cohesive agent. The Ti-Al coating was fabricated on the surface of electro-deposited nickel layer on copper matrix followed by the slurry pack cementation process. The effects of slurry pack cementation temperature on the microstructures and wear resistance of Ti-Al coating were studied. The results show that the microstructure of the coating changed from NiAl＋Ni3（Ti,Al） to NiAl ＋Ni3（Ti,Al）＋Ni4Ti3 to Ni4Ti3＋NiAl, and to NiAl＋Ni3（Ti,Al）＋NiTi with slurry pack cementation temperature ranging from 800 ℃ to 950 ℃ in 12 h. The friction coefficient of Ti-Al coating decreased and the hardness increased with increasing the slurry pack cementation temperature. The minimum friction coefficient was 1/3 and the minimum hardness was 5 times larger than that of pure copper.为了提高纯铜表面的耐磨性能,采用电镀/浆料包渗相结合的方法,以TiO2粉为渗Ti源,纯Al粉为还原剂,在Cu表面预镀Ni随后表面浆料包渗Ti-Al,制备Ti-Al共渗层。研究了包渗温度对Ti-Al渗层组织和耐磨性能的影响。采用SEM和XRD分析了渗层表面形貌和结构。结果表明:在800～950°C共渗12 h时,随着温度的升高,渗层组织变化过程为NiAl+Ni3(Ti,Al)→NiAl+Ni3(Ti,Al)+Ni4Ti3→Ni4Ti3+NiAl→NiAl+Ni3(Ti,Al)+NiTi;Ti-Al渗层的摩擦因数随着包渗温度的升高而降低,最小摩擦因数约为纯铜的1/3,最小硬度为纯铜的5倍。

关 键 词：Ti-Al coating Ni-Ti intermetallic compound Ni-Al intermetallic compound slurry pack cementation temperature wear resistance 

分 类 号：TG174.4[金属学及工艺—金属表面处理]