WC-Co-Cr涂层和0Cr13Ni5Mo基材的气体喷砂冲蚀行为  

Sand-blasting Erosion Behavior of HVOF Sprayed WC-Co-Cr Coatings and 0Cr13Ni5Mo Substrate

作　　者：李阳[1,2] 刘阳[1] 段德莉[1] 李曙[1] 

机构地区：[1]中国科学院金属研究所专用材料与器件研究部沈阳110016 [2]河北工程大学机电学院河北邯郸056038

出　　处：《中国表面工程》2013年第2期14-20,共7页China Surface Engineering

基　　金：国家自然科学基金(50475159)

摘　　要：研究不同结构HVOF热喷WC-Co-Cr涂层和0Cr13Ni5Mo基材的冲蚀行为,重点分析高速粒子冲击下涂层孔洞和层状结构等缺陷在不同攻角下的作用,提出高攻角气体喷砂冲蚀模型,解释了WC-Co-Cr涂层和0Cr13Ni5Mo基材的冲蚀行为规律。结果表明:低攻角时,涂层与基材的损伤机制均以微切削去除为主,涂层还伴有少量剥落,WC-Co-Cr涂层的耐冲蚀性能一般优于基材,但高孔隙率涂层更易切削导致冲蚀率比基材高。随攻角增大,涂层冲蚀率呈上升趋势而基材冲蚀率下降。高攻角时,层状结构明显的涂层其裂纹更易在层间萌生和扩展导致片状剥落,高孔隙率反而有利于吸收冲击能量和抑制裂纹扩展;基材则出现严重塑性变形。在气体喷砂条件下,涂层的层状结构对法向冲击极为敏感,攻角高于45°后,WC-Co-Cr涂层的冲蚀率为基材的1.3～4.1倍。The erosion behavior of HVOF sprayed WC-Co-Cr coatings with different microstructure and 0Crl3Ni5Mo substrate was investigated. Under the condition of high velocity impact condition, the effects of pores and laminar structure on erosion resistance of the coatings under different impingement angles were fo- cused on. A sand-blasting erosion model under high impingement angle was proposed to explain the erosion behavior of WC-Co-Cr coatings and 0Crl3NiSMo substrate. Results show that the dominant damage mecha- nism of coatings and substrate is micro-cutting and some detachments occur on coatings under low impinge- ment angle. The erosion resistance of WC-Co-Cr coatings is generally better than that of the substrate, how- ever, high porosity coating is easy to cut which makes the erosion resistance worse. The erosion rate of coat- ings presents uptrend and that of suhstrate declines with increasing impingement angle. Under high impinge- ment angle, the cracks in coating with obvious laminar structure are easy to initiate and prolong, which make much detachment of the coatings. The high porosity may absorb impact energy and prevent the cracks from prolonging, and serious plastic deformation occurs on the substrate. In sand-blasting condition, laminar struc- ture of the coating is more sensitive to normal impact and the erosion rate of WC-Co-Cr coatings is 1.3-4.1 times that of the substrate above 45° impingement angle.

关 键 词：WC—Co—Cr涂层 气体喷砂试验 冲蚀 攻角 

分 类 号：TG174.442[金属学及工艺—金属表面处理]