Abstract:
This paper describes the CCDS2000 detonation coating system and demonstrates its capability for depositing electrically insulating and wear-resistant aluminum oxide coatings. The dielectric strength of the coatings exceeds 25 kV/mm within a thickness range of 50–300 $\mu$m. The coatings exhibit an electrical resistivity $\rho_e$ > 2.67 $\times$ 10$^{13}$$\Omega$$\cdot$ cm at 20$^{\circ}$C and a relative humidity of up to 59%. A further increase in humidity caused a sharp decrease in $\rho_e$ by 2–3 orders of magnitude. The coatings exhibit adhesion to a steel substrate of 60–70 MPa, a microhardness value HV$_{0,1}$ = 1522–1655, and a porosity of 0.35–1.00%. Evidently, the C$_2$H$_2$ + 2O$_2$ detonation mixture is optimal for obtaining electrically insulating coatings, whereas the 0,69C$_2$H$_2$+ 0,53C$_3$H$_6$ + 2,51O$_2$ mixture yields the best wear resistance. The use of the dual-fuel mixture results in a fourfold increase in abrasive wear resistance and a 34% improvement in erosive wear resistance.
Fulltext:
PDF file (1750 kB)
First page:
PDF file