Properties of high velocity arc sprayed coatings

High Velocity Air Fuel Electric arc spraying (HVAF Arc) is a thermal spraying technology that is quite similar to electric arc spraying. The difference between these two types of spraying equipment is that whereas the electric arc spraying technology uses compressed air as the atomizing gas, HVAF Arc uses the combustion products of propane and air. In the present study, results from tests made to HVAF Arc coatings that have been sprayed with different spraying parameters are presented. These tests include composition and thickness analyses, surface roughness tests, Vickers hardness tests, an erosion and a corrosion test. According to the results, HVAF Arc coatings have fine microstructure, with low porosity, but are quite heavily oxidized. They are typically more oxidized than coatings made without using propane as a process gas, though the HVAF Arc coatings have lower surface roughness, less pores and slightly higher hardness, due to the amount of oxides in the coating.