电弧喷涂纳米结构涂层的组织与磨损性能
Microstructure and Wear Properties of Nanostructured Coatings Prepared by wire Arc Spray
-
摘要: 基于机器人自动化高速电弧喷涂技术在45#钢基体上制备了铁基纳米结构涂层.研究了纳米结构涂层在不同磨损速度?不同载荷下的磨损行为,并利用3Cr13涂层进行对比试验.采用扫描电镜?能谱分析仪,透射电镜和X射线衍射仪等设备对涂层的组织结构进行了表征,利用纳米压痕仪对涂层的力学性能进行了分析.结果表明:涂层的组织主要由非晶相和α(Fe,Cr)相纳米晶组成;平均尺寸为46nm的α(Fe,Cr)相纳米晶均匀分布于非晶基体内.涂层的组织均匀,结构致密,平均孔隙率含量为1.7%.纳米结构涂层具有较高的显微硬度;随着磨损速度升高,载荷增加,纳米结构涂层的磨损量也随之增加.纳米结构涂层具有良好的耐磨性,同一磨损条件下,其相对耐磨性为3Cr13涂层的2.6倍.纳米结构涂层主要磨损机制为脆性断裂机制.Abstract: This paper investigated the effects of wear paramaters , such as sliding speed and load , on the wear properties of Fe-based nanostructured coating . A series of Fe - based nanostructured coatings were prepared by using wire arc spray. The microstructure of the coating was characterized by SEM , EDAX , XRD and TEM . The mechanical properties of the coating were measure d by nanoindention . The wear tests of coatings were conducted on a MM2OO wear tester . The microstructure of the coating consisted of amorphous phase and nanocrystalline ( Fc , Cr ) Phase . The nano- grains with an average size of 46 nm were homogenously dispersed in an amorphous phase matrix . The coating was nearly full- densed with a porosity of 1. 7 % and high hardness . With the increase of sliding speed and load , the wear mass of the coating increased . The nanostructured coating had excellent wear resistance , i?e . the nanostructured coating was 2 . 6 times as high as that of the 3Crl3 coating . The failure mechanism of the coatings was brittle fracture