Fabrication of Y2O3 coatings by cold-spray

As a candidate material against plasma etching, yttrium oxide has been coated onto etching chamber by plasma spray technique. However, the plasma spray technique introduces undesirable coating properties such as porous structure and deleterious thermal effects. To reduce the disadvantage of thermal impact, cold spray was used as an alternative technology to deposit thick and dense yttrium oxide coatings. Many studies have shown that the powders suitable for cold spray process should be with a size around 20μm. However, the Y2O3 are ceramics, it is difficult to form coatings by cold spray due to the lack of ductility when using the powders with a size about 20 μm. It is also difficult for nano-particles to get through the bow shock of cold spray process, which may cause deceleration or even deflection of lighter particles away from the surface, and therefore fail to be cold sprayed. In this paper, we use Y2O3 with an original average size of 30 nm to form agglomerated Y2O3 particles b