Laser preparation and characterization of NiCr-MoS2-M self-lubricating wear-resistant coating
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摘要: 为了提高挤出机螺杆表面的耐磨损性能,采用激光熔覆技术在38CrMoAl钢表面制备NiCr-MoS2-M(M为CeO2-TiC-Cr3C2-V)耐磨自润滑复合涂层。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)及附带的能谱仪分析了涂层的物相组成及显微组织,采用显微硬度计测试了涂层的显微硬度分布,并在室温条件下测试了上述涂层的干滑动摩擦学性能,取得了相关的数据。结果表明,XRD测试结果显示强化层主要由FeNi,Ni3Fe和Cr-Ni-Fe-C固溶体组成;用SEM观察发现强化层由固溶体枝晶、富Cr共晶和未熔MoS2颗粒组成。涂层中的显微硬度为313.7HV,约为基体显微硬度(332.6HV)的94.32%;摩擦系数为0.513,约为基体摩擦系数(0.315)的1.63倍;磨损量为58.56110-3mm3,约为基体磨损量(4.9110-3mm3)的11.9倍。这一结果对进一步优化工艺参量,以提高强化层的综合力学性能是有帮助的。Abstract: To improve the wear resistance of extruder screws, self-lubricating wear-resistant NiCr-MoS2-M coating was fabricated on 38CrMoAl substrates by laser cladding. Phase composition and microstructures were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Microhardness was measured with a microhardness tester. Tribological properties of the fabricated composite coatings were evaluated under dry sliding condition at room-temperature. The related data were obtained through theoretical analysis and experimental verification. XRD results show that the reinforced layer is composed of FeNi,Ni3Fe and Cr-Ni-Fe-C solid solution. According to SEM observation, the reinforced layer consists of solid solution dendrites, eutectic rich in Cr and undissolved MoS2 particles. The microhardness of the coating is about 313.7HV, about 94.32% of the matrix (332.6HV). Friction coefficient is about 0.513, about 1.63 times of the matrix (0.315). Wear loss of coatings is about 58.56110-3mm3, about 11.9 times of the matrix (4.9110-3mm3). This result is helpful for the further optimization of process parameters to improve the comprehensive mechanical properties of the reinforced layers.
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Keywords:
- laser technique /
- laser cladding /
- self-lubrication /
- MoS2 /
- extruder screw
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期刊类型引用(2)
1. 李凌宇，石岩，李镇. 激光沉积铁基涂层微观组织与耐磨性能研究. 长春理工大学学报(自然科学版). 2018(04): 25-30 . 
百度学术
2. 李博雅，曹志强. 金属基固体自润滑复合涂层及其制备技术研究进展. 表面技术. 2017(09): 32-38 . 百度学术
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