高速电弧喷涂再制造曲轴的使用寿命与涂层的结合强度和耐磨性有很大的关系。为了提高涂层的性能,研究了新型FeAlCr/3Crl3复合涂层的组织结构和力学性能,采用扫描电镜(SEM)、能谱仪(EDAx)和x射线衍射仪分析了涂层的微观结构、相组成和残余应力。利用显微硬度计和CETR微动摩擦磨损试验机等试验设备对涂层的力学性能进行了分析。结果表明,喷涂FeAlCr粉芯丝材作为打底层,合金元素反应充分,复合涂层组织均匀、致密,空隙率约9.87%。复合涂层相组成主要由韧性相a—Fe和硬质相Cr23C6、(Fe,Cr)固溶体组成,氧化物含量较低,约3.2%,复合涂层平均残余应力较小,约67.6MPa,平均显微硬度HV01为4000MPa,结合强度约46.6MPa,油润滑高载摩擦条件下复合涂层表现出较好的耐磨性能。
The working life of a crankshaft remanufactured by robot-based automatic high velocity arc spraying has the relation with wear resistance and adhesive strength of its coating. This paper studied the characteristics and properties of a newly-designed composite coating FeAlCr/3Crl3 aimed at improving the martensitic stainless 3Cr13 coatings. Microstructures, residual stress and wear resistance of the composite coating were investigated by SEM, XRD and CETR wear tester, respectively. The results show that when the FeAlCr cored wire is used as prime coating the elements react fully. The composite coating compact and uniform and its porosity is about 9.87%. The phases of the coating are a-Fe, Cr23C6, (Fe, Cr) solid solution and Ni3A1, among which the content of oxide is as low as 3.2 %. The average residual stress, microhardness and adhesive strength of the coating are 67.6 MPa, HV0.1 4000 MPa and 46.6 MPa, respectively. The FeAlCr/3Crl3 composite coatings under the dry or lubricating abrasion have higher wear resistance than the substrate.