Alumina Coatings Produced Using the CCDS2000 Detonation System

Abstract

In this paper, we describe the CCDS2000 detonation system and demonstrate its capabilities for producing insulating and wear-resistant alumina coatings. The dielectric strength of such coatings is above 25 kV/mm at thicknesses in the range 50–300 μm. The resistivity of the coatings at a temperature of 20°C and relative humidity below 59% is ρ_e > 2.67 × 10¹³ Ω cm. As humidity increases, ρ_e drops sharply, by two to three orders of magnitude. The adhesion of the coatings to a steel substrate is up to 60–70 MPa, their microhardness is HV_0.1 = 1522–1655, and their porosity ranges from 0.35 to 1.00%. Our results demonstrate that, to obtain electrical insulation coatings, it is reasonable to use a C₂H₂ + 2O₂ detonating mixture, and that optimal wear resistance parameters can be obtained with a 0.69C₂H₂ + 0.53C₃H₆ + 2.51O₂ mixture. Switching to the dual-fuel mixture ensures a fourfold increase in abrasion resistance and a 34% increase in erosion resistance.