Investigation of morphology and texture properties of WSi2 coatings on W substrate based on contact-mode AFM and EBSD

The WSi2 coatings on W substrate were successfully prepared by hot dip silicon-plating (HDS) method. The surface roughness, surface and cross section morphology, and texture evolution were characterized by fielde-mission scanning electron microscope (FE-SEM), energy dispersive spectroscopy (EDS), atomic force microscope (AFM), and electron back scattering diffraction (EBSD). The FE-SEM results show that the WSi2 coatings have a good adhesion with the substrate, and no microcracks and pores are observed at the surface. AFM images show that the WSi2 coatings have a similar and homogeneous surface morphology with a granular structure and nanoscale roughness, and most of surface vertical heights are less than 600 nm. The low roughness is observed when the deposition temperature is 1470 degrees C to 1530 degrees C, the Ra and Rq are 82.1-115.6 nm and 109.1-140.3 nm, respectively. EBSD analysis indicates that the WSi2 coatings have typical {100} and {110} textures with the coating thickness of 18 to 42 mu m and average grain size of 6.78 to 10.92 mu m.