激光熔覆SiC/不锈钢粉末复合涂层的组织与性能

用 2 k W Nd:YAG激光在 4 0 Cr钢基体上制取了 Si C强化的 Fe基复合材料涂层 ,并对熔覆层进行了显微组织结构和性能测试 .加入的 Si C包括颗粒状和纤维状两种形态 ,通过调整颗粒状Si Cp和纤维状 Si Cf的加入量 ,研究了 Si C在激光熔覆过程中的演变、存在形式及对熔覆层硬度的影响 .结果表明 ,随着加入量的增加 ,熔覆层中未熔 Si C含量增加 ,熔覆层硬度也随之提高 ;对比加入颗粒状和纤维状 Si C的熔覆层的显微硬度表明 ,同含量情况下纤维状 Si C的强化效果更显著 ;造成熔覆层硬度显著提高的原因是未熔 Si C,析出相 Fe Si C的弥散强化和熔入的 Si,C元素引起的固溶强化作用 .

Microstructure and Performance of the SiC/Stainless Steel Composite Coating Produced by Nd:YAG Laser Cladding

SiC reinforced iron matrix composite coatings have been successfully produced by using a 2 kW Nd:YAG laser on a 40Cr steel substrate, and microstructure analysis and performance testing of the coatings are carried out. There are two forms of SiC in the experiment: particle and fiber. By adjusting the adding content of SiCp and of SiCf, evolution of SiC of different forms during laser cladding, existing forms of SiC in cladding layers and affection on hardness of cladding layers are studied. The results show that during laser cladding, SiC of different forms is decompounded partially; with the increasing of the SiC adding content, the quantity of un-melt SiC increases and hardness of cladding layers improves. Comparing the hardness of SiC particle reinforced coating with the SiC fiber reinforced coating, the reinforcing effecting of SiC fiber is higher; the main reasons bring hardness remarkable improvement are disperse reinforcement of un-melt SiC and propitiation FeSiC, and solution reinforcement of decompounded Si, C.