High Temperature Oxidation and Oxyacetylene Ablation Properties of ZrB2-ZrC-SiC Ultra-High Temperature Composite Ceramic Coatings Deposited on C/C Composites by Laser Cladding

Abstract

In order to improve the high temperature oxidation and ablation resistance of C/C composites, ZrB2-ZrC-SiC ultra-high temperature composite ceramic coatings were prepared on C/C composites by laser cladding using Zr, B4C, and Si as raw materials. The microstructure of the coating was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Air isothermal oxidation (1600 °C, 80 min) and oxyacetylene flame ablation (2400 kW/m2, 300 s) were used to evaluate the high-temperature oxidation and ablation properties of the coating, respectively. The results show that the microstructure of laser cladding coating is a totem of black and white. The white part is mainly the first solidified high melting point ZrB2 phase, and the black part is the latter solidified eutectic structure, which is mainly composed of ZrB2(ZrB12)-ZrC or ZrB2(ZrB12)-SiC two phases. After oxidation at 1600 °C and 80 min, the coating is mainly composed of ZrO2 and ZrSiO4 phases, and ZrSiO4 is basically distributed among ZrO2 particles. The high temperature oxidation and ablation properties of the coating are better than the C/C composite matrix, and the mass ablation rate of the coating is about 1/4 of the latter.

High speed laser cladding as a new approach to prepare ultra-high temperature ceramic coatings

“…That is, the whole coating would have a strong bonding ability with substrate to protect the substrate from ultra-high temperature thermal ablation. Compared with the work on the SLM fabrication of a eutectic UHTC coating reported by King et al [14] from AFRL, the HSLC process not only accomplishes the preparation of UHTC coatings with relatively integrated microstructure, but also a strong bonding with the substrate, which paves a new way for fabricating UHTC coatings. Besides, Tan et al [41] prepared Ta-Hf-W-C solid solution coating with the plasma spraying technology on the refractory tungsten substrate.…”

“…For years, the laser surface technology is rarely mentioned to fabricate UHTC coatings as the extremely high energy density of laser and the inherent brittleness of UHTC materials. A representative work from the research group of the US Air Force Research Laboratory (AFRL) [14] has made an attempt to prepare ZrB 2 -ZrC-B 4 C composite ceramic coating on tungsten substrate by selective laser melting (SLM) technology for the first time. However, the thermal expansion mismatch between the ceramic coating and the substrate was proved to be detrimental to coating integrity after cross-sectioning.…”

The Effect of an Ultrasonic Field on the Microstructure and Tribological Behavior of ZrB2/ZrC+Ni60A/WC Composite Coating Applied by Laser Cladding

“…Metallic nickel-based materials, including Ni60A, are among the materials that are used as coating materials [20]. To increase the efficiency of the coating, various ceramic materials such as ZrB 2 and ZrC have been recommended as reinforcements in Ni60A due to their excellent thermal stability, corrosion, and wear resistance [21]. To reduce the probability of the formation of Ni-Zr intermetallic compounds, adding WC is recommended [22].…”