Effect of powder particle size on microstructure and properties of low pressure cold sprayed high aluminium bronze coating

Abstract

High-aluminum bronze alloy powder was mixed with 16 wt% Al2O3 powder to prepare low-pressure gas dynamic spray coatings with different sized powder particles. The mechanical properties of coatings were tested and the surface, cross section and stretch section of coatings were observed by scanning electron microscopy. Uniform experiment was performed to analyze the effects of particle size of the high-aluminum bronze and Al2O3 powder on coating performance. Experimental results shows that the degree of deformation of the high-aluminum bronze particle in the coating increased with decreasing particle size in the high-aluminum bronze and Al2O3 in the mixed powder. The degree of deformation of the high-aluminum bronze particle in the coating affected the mechanical properties of the coating showing a linear relationship between powder size and coating performance. When the particle size of Al2O3 and high-aluminum bronze particle ranged between 23-25 μm, the coating has the outstanding mechanical properties.