电子束预处理40Cr表面涂镀Cr层工艺分析

Process Analysis of Coating Cr Layer on 40Cr After Surface Electron Beam Pretreatment

针对涂层硬度梯度过渡急剧、涂层与基体的结合力不足的问题,利用电子束对40Cr材料表面进行预处理,然后溅射Cr涂层,考察电子束预处理工艺对材料表面形貌、硬度分布、粗糙度、结合力及摩擦磨损等性能的影响规律。研究结果表明,电子束预处理后,基体硬度提高79%~109%,镀Cr后硬度进一步提高14%~25%,基体熔坑形貌不能完全被Cr层覆盖,涂层粗糙度高于基体未预处理涂层。40Cr经电子束预处理后溅射Cr层的结合力可提高约41.7%,主要原因是表面晶体结构及状态影响了涂层结合力。电子束预处理延长了涂层初磨阶段时间,增强了表面的摩擦磨损性能。

To solve the issues of excessive coating hardness gradient and weak bonding force between substrate and coating,a Cr coating was sputtered on 40 Cr surface pre-irradiated by electron beams.The influencing regularities of electron beam pre-irradiation process on surface morphology,hardness distribution,roughness,bonding force,and frictional wear properties of the material were investigated.The results suggested that the hardness of substrate was improved by 79%-109% after electron beam pre-irradiation,and was further increased by 14%-25% after sputtered Cr coating.Moreover,crater morphology on the substrate surface was not completely covered by Cr coating.The Cr coating sputtered on pre-irradiated substrate had a higher roughness compared to that sputtered on substrate without pre-irradiation,and a bonding force of about 41.7%larger than that sputtered on substrate without preirradiation.The surface tribological properties of the coating were improved since its preliminary grinding time was extended due to electron beam pre-irradiation.