Liu Yang, Li Guodong, Jiang Wenting
State Key Laboratory of Powder Metallurgy, Central South University; Changsha 410012, Hunan, China.
Materials (Basel). 2019 May 10;12(9):1537. doi: 10.3390/ma12091537.
SiC particles (SiC)-reinforced Al-Si matrix composite coatings were synthesized on 4032 aluminum alloy by laser cladding using powder mixtures of Al-20 wt.% Si alloy and electroless copper-plated SiC particles (SiC). The effects of SiC content on microstructure, phase composition, and microhardness of the SiC/Al-Si laser cladding layer (LCL) were investigated systematically. The results showed that the microstructure of SiC/Al-Si LCL was mainly composed of undissolved SiC, lump-like primary Si, lump-like AlCu, plate-like AlSiC, and Al-Si-Cu ternary eutectic. In addition, the eutectic microstructure became finer with the increasing of SiC content. The average microhardness of the LCL increased with the increasing of SiC content. When SiC content was 50 wt.%, the average microhardness of the LCL reached 508 HV, which was about 3.5 times larger than that of the substrate. The LCL reinforced with a SiC content of 30 wt.% exhibits the best wear resistance.
采用 Al-20 wt.% Si 合金与化学镀铜 SiC 颗粒（SiC）的粉末混合物，通过激光熔覆在 4032 铝合金上制备了 SiC 颗粒增强 Al-Si 基复合涂层。系统研究了 SiC 含量对 SiC/Al-Si 激光熔覆层（LCL）的微观结构、相组成和显微硬度的影响。结果表明，SiC/Al-Si LCL 的微观结构主要由未溶解的 SiC、块状初生 Si、块状 AlCu、片状 AlSiC 和 Al-Si-Cu 三元共晶组成。此外，随着 SiC 含量的增加，共晶组织变得更细。LCL 的平均显微硬度随 SiC 含量的增加而提高。当 SiC 含量为 50 wt.% 时，LCL 的平均显微硬度达到 508 HV，约为基体的 3.5 倍。SiC 含量为 30 wt.% 的 LCL 具有最佳的耐磨性。
