Properties of Al2O3 coatings obtained by electric arc plasma method in "dynamic vacuum"

The results of studies of the influence of the electrophysical characteristics of a heterogeneous plasma flow on the properties of Al2O3 coatings (phase composition, adhesion, porosity) during plasma arc thermal spraying on a steel grade 20 in dynamic vacuum, in the pressure range from 7 to 50 kPa and at 100 kPa are presented. As well as the results for different plasma thermal spraying modes (power, consumption rate of plasma-forming gas and powder, pressure in the chamber). For the plasma torch design in this work, it was shown that Al2O3 particles are deposited most efficiently when their size is up to 100 μm, with an arc current of 300 A, flow rates for powder 0.1 g/s and for plasma-forming gas of up to 1 g/s in the pressure range (2.0-3.0) * 104 Pa.