稀土元素对Cu14AlX涂层组织和摩擦性能的影响

采用气雾水冷方法制备Ce质量分数分别为0和0.6%的Cu14AlX合金粉末,超音速等离子喷涂的方法制备喷涂层,利用光学显微镜、XRD、SEM-EDS以及EPMA分析Ce元素对Cu14AlX喷涂层表面组织形貌、合金相结构和化学成分的影响。在边界润滑条件下,比较不同Ce含量下喷涂层摩擦磨损性能,用SEM-EDS分析喷涂层磨损形貌及成分变化。结果表明:Ce的加入可以细化Cu14AlX喷涂层组织,使得Fe元素和K相增多且分布更加均匀,提高了喷涂层的耐磨性。两种喷涂层有不同的磨损形式,随着载荷的增大,不含Ce的喷涂层粘着磨损严重并伴随轻微的磨粒磨损,在高载荷(4.90Mpa)下,由粘着磨损转化为磨粒磨损;含Ce(质量分数)0.6%的喷涂层以轻度磨粒磨损为主,在高载荷下,转变为中度磨粒磨损,部分区域出现加工硬化现象.

Effect of Ce on the Microstructure and Wear Behavior of Cu14AlX Coatings

The effects of rare earth Ce on the microstructure and wear resistance of supersonic plasma spraying Cu14AlX coatings were investigated. The powders of Cu14AlX alloy with 0 and 0.6% Ce were sprayed on 45 carbon steel substrate. Microstructure, compositions and phase structure of Cu14AlX coatings were investigated by light microscopy, XRD, SEM and EPMA. Tribological properties of the coatings were tested under boundary tribological condition. The results show that the addition of Ce (0.6%) into Cu14AlX coating refines the microstructure of the coating, and causes the Fe element and K phase increasing and equally distributing, so the wear resistance of the spray coatings is improved.The two coatings have different wear mechanism. The abrasion format of the coatings without Ce addition become serious adhesion wear accompanied with minor abrasive wear, eventually into abrasive wear at high loads(4.90 MPa) when the load increases. The main abrasion format of the coatings with 0.6% Ce is mild abrasive wear, eventually become moderately abrasive wear at high loads (4.90 MPa), and some areas of friction hardening occurs.