激光熔覆制备SiC／Ni基复合涂层及其耐冲蚀性能

Synthesis of SiC/Ni Composite Coatings by Laser Cladding and Property of Erosion Resistance

采用激光熔覆技术在45#钢表面分别制备了Ni60A涂层及SiC/Ni60A复合涂层。采用光学显微镜(OM)、扫描电镜(SEM)和X射线衍射(XRD)仪对涂层进行了显微组织和物相分析,并测试了熔覆层的显微硬度和耐冲蚀磨损性能。结果表明,在激光作用下,SiC由于具有较小的生成热容易溶解在合金涂层中。熔覆层的物相主要由γ(Ni-Cr-Fe)固溶体及Fe7C3,Fe0.79C0.12Si0.09等化合物组成。在固溶强化、第二相强化及细晶强化的共同作用下,SiC/Ni60A涂层的抗冲蚀性能显著提高,涂层的显微硬度也明显增加。

Ni60A and SiC/Ni60A coatings had been synthesized by laser cladding on 45^# steel substrate. Optical microscopy （OM）, scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to analyse the microstructure and metallograpbic. The microbardness and erosion resistance performance bad also been investigated. Results reveal that SiC can easily be dissolved in alloy coatings due to its low heat of formation. The phase of coatings is mainly composed of y（Ni-Cr-Fe） solid solution, FeTC3 and Fe0.79C0.12Si0.09 As the coaction of solution strengthening, second-phase strengthening and fine-crystal strengthening, the erosion performance of SiC/ Ni60A composite coatings has been significantly increased and the microbardness has also been evidently raised.