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利用激光熔覆技术,在A3钢表面制备出了原位生成TaC颗粒强化的镍基复合涂层。使用金相显微镜、扫描电镜(SEM)、电子能谱(EDS)和X射线衍射(XRD)仪对熔覆层进行了显微组织和物相分析,并测试了熔覆层显微硬度及摩擦性能。结果表明,在适当的工艺条件下,激光熔覆制备原位生成TaC颗粒增强镍基复合涂层成形良好、表面光滑,涂层与基体呈现良好的冶金结合。熔覆层组织由原位生成的TaC颗粒相+Cr3C2与γ(Cr-Ni-Fe-C)的枝状共晶相+γ(Cr-Ni-Fe-C)基体组成。由于TaC颗粒强化相的形成及其均匀弥散分布,既提高了涂层中的强化相比例,又细化了组织,使得TaC/Ni60激光熔覆层具有高的硬度(平均硬度HV0.31100),与纯Ni60熔覆层相比,耐磨性提高4倍。
The laser cladding technology was used to prepare in-situ TaC particles reinforced Ni-based composite coatings on the surface of A3 steel. The microstructure and phase analysis of the coating were investigated by metallographic microscope, scanning electron microscopy (SEM), electron spectroscopy (EDS) and X-ray diffraction (XRD). The microhardness and friction performance. The results show that the laser cladding preparation of in-situ TaC particles enhanced nickel-base composite coating formed well, the surface is smooth, the coating and the substrate showed a good metallurgical bond under the appropriate process conditions. The microstructure of the coating consists of in-situ dendritic eutectic phase + γ (Cr-Ni-Fe-C) matrix of TaC particles + Cr3C2 and γ (Cr-Ni-Fe-C) Due to the formation and uniform dispersion of TaC particles, the TaC / Ni60 laser cladding layer has high hardness (average hardness HV0.31100), which not only improves the proportion of strengthening phase in the coating but also refines the microstructure. Compared with the pure Ni60 cladding, wear resistance increased by 4 times.