Experimental study of cold gas spraying through a mask. Part 1

Abstract

The paper presents experimental data for production of a coating using cold gas dynamic spraying with a mask with transverse size in the range 0.3–1 mm and placed at different distances from the substrate. The coated samples were produced, and coating profiles were measured in the vicinity of the masked zone. The tests with depositing of aluminum powder and copper powder demonstrated that the distinct profile of masked zone is obtained for placing the mask at a distance below critical (depending of spray conditions). The most accurate boundary of the masked zone takes place at a minimal distance (depends on the coating thickness). Depending on the spraying conditions, the increase in the mask-substrate distance may result either in monotonic decline of the masked zone width or a slight increase for a certain range. Experimental data are generalized by normalizing with the transverse size of the mask (under other equal conditions).