Zircon-based ceramic coatings formed by a new multi-chamber gas-dynamic accelerator

Abstract

In this work, dense zircon-based ceramic coatings were obtained from inexpensive zircon powder on a steel substrate by using a newmulti-chamber gas-dynamic accelerator. Themicrostructure and phase composition of the coating were characterized by scanning electron microscopy, optical microscopy, and X-ray diffraction. The mechanical properties of the coatings were evaluated using microindentation, wear tests and bonding strength tests. The results showed that the obtained zircon-based ceramic coatings were continuous without cracks and bonded well with substrate without a sublayer. The zircon-based ceramic coatings consisted of c-ZrO 2 (major phase), m-ZrO 2 and SiO 2 . The zircon-based ceramic coatings had a porosity of 0.1%, hardness of 526 ± 65 HV0.2, and a fracture toughness of 2.5 ± 0.6 (MPa·m 1/2 ). The coatings showed the low specific wear rate and average erosion rate. The failure mode occurring in the tested coatings was cohesive.