Influence of Wire Feed Rate of High-Speed Electric Arc Metallisation on Structure and Corrosion Properties of 30hgsa Steel Coatings

The study examines the porosity characteristics, corrosion analysis, and microstructure of iron-based coatings sprayed by supersonic arc metallisation in order to understand the regularity of the influence of the parameters by wire feed rate dependence. The performance of iron-based coatings depends on the integrity of the coating structure. Optimisation of arc spraying parameters allows minimising defects (pores, grain boundaries, unmelted particles, oxides and microcracks) that deteriorate coating properties. At high current levels, the microstructure of the coatings becomes more dense and the particle size decreases, also the average pore size decreases. As the wire feed rate increases, the value of current increases, which leads to the release of more heat energy at the arc to melt the wire and consequently favours the formation of dense coatings with low porosity.