Fe-Cr-Ti-Ccomposite powder was prepared by precursor carbonization-composition process using the mixture of ferrotitanium, chromium, iron powders and precursor sucrose as raw materials. In situ synthesized TiC particle reinforced composite coating was fabricated on substrate of Q235 steel by reactive plasma cladding process using Fe-Cr-Ti-C composite powder. Microslructure of the coating was observed by scanning electron microscope (SEM) ,the phases in the coating were determined by X-ray diffraction (XRD) ,and the wear resistance of the composite coating was evaluated under dry sliding wear test conditions at room temperature. The results indicate that the composite coating consists of in-situ the reinforcing TiC carbide, ( Cr ,Fe)7C3eutectics and austenitic ,and is metallurgical^ bonded to ihe Q235 steel substrate. TiC carbide in the composite coating showed a gradient distribution. TiC particles present granular in the fusion zone and central zone,and present dendritic in the surface of the composite coating. There is little difference in the hardness of the coating from surface to fusion zone, and the average hardness of the coating is approximately HV02750,3.2 times as the base. The wear mass loss of Q235 base material is 12 times as that of the composite coating.%TiC增强涂层以钛铁粉、铁粉、铬粉和碳的前驱体(蔗糖)等为原料,通过前驱体碳化复合技术制备了Fe-Cr-Ti-C等离子熔覆复合粉末,并通过等离子熔覆技术在Q235钢表面成功原位合成.采用SEM、XRD和EDS对涂层的相组成和显微组织结构进行了分析,并在室温干滑动磨损条件下测试了该涂层的耐磨性能.结果表明,等离子熔覆涂层由原位合成的TiC相和(Cr,Fe)7C3共晶相与奥氏体相构成,与基材完全冶金结合.涂层中碳化物TiC呈现梯度分布,并且涂层的熔合区和中部区域TiC颗粒形状大多呈现粒状,涂层的表层区域部分TiC颗粒呈现树枝状.涂层的硬度从表面到熔合区相差不大,平均显微硬度约是HV02750,是基体金属的3.2倍.涂层磨损质量约是基体金属的1/12,具有良好的耐磨性能.
展开▼
