大气等离子喷涂制备Fe基非晶涂层及微观结构表征

选用Fe-10W-4Cr-3Ni-2Mo-4B-4Si-1C(质量比)合金粉末作为喷涂原料,采用大气等离子喷涂工艺在1Cr18Ni9Ti不锈钢基底上制备了Fe基涂层。利用扫描电镜、透射电镜和X射线衍射仪表征了粉末和涂层的相组成和微观形貌;用Olycia m3分析软件对涂层的孔隙率进行测定;用热分析系统对喷涂粉末和涂层从室温到1 173K范围的DSC曲线进行记录;同时,测定了涂层的显微硬度和结合强度。结果表明:大气等离子喷涂制备的Fe基涂层与基底的结合良好,涂层较为致密并且存在灰色氧化带组织,表现出典型的层状组织结构;涂层不但具有低的表面粗糙度和孔隙率,而且具有高的显微硬度和结合强度;所制备涂层中的非晶含量约为89.2%(质量分数),涂层中形成的晶相组织为纳米晶结构。

Preparation and Microstructure Characterization of Atmosphere Plasma Sprayed Febased Amorphous Coating

Fe10W4Cr3Ni2Mo4B4Si1C (mass ratio) alloy powders were sprayed onto 1Cr18Ni9Ti stainless steel substrate using atmospheric plasma spraying (APS) system. Microstructure and phase composition of the powders and assprayed Febased amorphous coatings were investigated by scanning electron microscopy(SEM), transmission electron microscopy(TEM) and Xray diffraction(XRD). The porosity of the Febased amorphous coating was measured using an Olycia m3 image microscope. Moreover, the DSC curves of spraying powder and assprayed Febased amorphous coating were determined from room temperature to 1 173 K by means of differential scanning calorimetry(DSC), and their microhardness and bonding strength were measured. The results show that good adhesion is obtained between the Febased amorphous coating and the substrate, coating prepared by APS is dense, but with grey oxidation existing in the coating. Besides, the as sprayed Febased amorphous coating has typical lamellar structure. At the same time, the coating has not only low surface roughness and porosity, but also high microhardness and adhesion strength. The relative content of the amorphous phase of the coating is determined to be about 89.2% (mass fraction), and the formed metallurgical structure in the assprayed coating is nanocrystalline.