以Fe60合金粉末为原材料, 通过添加1%～5%的SiC形成复合合金粉末, 利用激光直接沉积技术在Q235钢表面制备SiC增强Fe60合金高耐磨涂层, 主要应用OM、SEM、EDS、XRD、显微硬度测试和摩擦磨损等分析手段对样品的组织结构及性能进行了研究。结果表明, 在优化的激光工艺参数: 功率1 700 W、扫描速度6 mm/s、送粉量8.8 g/min、搭接率30％、光斑直径4 mm×4 mm和300 ℃预热等条件下, 成功制备出了无裂纹缺陷厚度达到6 mm的Fe基合金涂层; 沉积层组织由等轴晶、枝晶、柱状晶组成, 主要由α-Fe、γ-Fe及Cr23C6、Fe2B、Cr3Si原位增强相组成; 发现在300 ℃温度下预热能够有效消除制备高C高Cr含量Fe基涂层易出现裂纹的难题; 当SiC添加量为3％时, 制备涂层具有最高的硬度达到1 072 HV, 比未添加SiC的合金涂层提高了284 HV, 具有良好的耐磨性能。

With Fe60 alloy powder as raw material and by adding SiC 1%~5% to form composite alloy powder, high wear resistant coating of SiC reinforced Fe60 alloy were formed on the surface of Q235 steel by laser direct deposition technology. The main application of OM, SEM, EDS, XRD, micro hardness test and friction and wear analysis method were studied for the sample’s structure and performance. Results showed that laser process parameters in optimization: power 1 700 W, scanning speed 6 mm/s, powder feed rate 8.8 g/min, lap ratio 30%, spot diameter 4 mm × 4 mm and 300 ℃ preheating and other conditions, the Fe based alloy coating with no crack defect thickness of 6 mm was successfully prepared; the microstructure of the deposited layer was composed of equal axial grains, dendrites and columnar crystals and mainly composed of α-Fe、γ-Fe and Cr23C6、Fe2B、Cr3Si in situ reinforced phase composition; the problem of cracks of preparing high C content based coating with high Cr content and high Fe content can be effectively eliminated by preheating at the temperature of 300 ℃; when the SiC content was 3%, the coating has the highest hardness of 1 072 HV, compared with the alloy coating without adding SiC increase 284 HV, which has good wear resistance.