Synthesis, Microstructural Characterization, and Mechanical Property Evaluation of Vacuum Plasma Sprayed Tantalum Carbide

Abstract

Tantalum carbide (TaC) is an ultra‐high‐temperature ceramic for potential applications as protective coating, furnace components, propulsion liners for space shuttles and aircrafts, etc. Microstructural and mechanical behavior of vacuum plasma‐sprayed (VPS) TaC has been investigated in the present study. Apart from major TaC phase, microstructural definitions elucidated Ta2C, non‐stoichiometric TaCx phases (0.83≤x≤0.94), partial grain formation, polygonization of grains, and inhomogeneous C/Ta ratios in the sprayed structure. Near‐isotropy in the fracture–toughness ratio (Kaxial/Ktrans=1.01) is attributed to compact coating, fine‐closed porosity, and distribution of non‐stoichiometric phases.

TaC–NbC formed by spark plasma sintering with the addition of sintering additives

“…UHTCs such as TaC, NbC, VC, and HfC, have been consolidated using conventional hot pressing, 3),4) pressureless sintering, 5),6) vacuum plasma spraying, 7) and high frequency induction heating.…”

Microstructure and Mechanical Properties of Nanofiller Reinforced Tantalum-Niobium Carbide Formed by Spark Plasma Sintering

“…Tantalum Carbide, as well as other UHTC materials such as NbC, VC, and HfC, has been consolidated into bulk form using various processing approaches (outlined in Table 3) including hot pressing [26][27][28][29][30][31], pressureless sintering [32,33], vacuum plasma spraying [34], high frequency induction heating [35,36], and spark plasma sintering [37][38][39][40]. Differences in heating and cooling rates, temperatures, dwell times, and pressures will impact the phase formation, microstructures, and densification of the final product.…”

“…Belani et al [34] fabricated freestanding TaC structures by deposition on a graphite substrate ( Figure 8). …”

Role of carbon nanotube dispersion in fracture toughening of plasma sprayed aluminum oxide - carbon nanotube nanocomposite coating

“…Spray dried powders are spherical and free flowing, which are consequently sieved to the ideal powder particle size range of 15-60 pm required for plasma spraying. High quality thermal spraying of micro and nanostructured coatings such as WC-Co, TaC, and A12O 3 -TiO 2 are described in literature [33,87,98,114].…”

“…But, inherent brittleness of ceramics have created a need for enhancing the fracture toughness and flexural bend strength of the ceramics [1,3,4,12,49,53,54]. The structural ceramics can be broadly classified into non-oxide and oxide ceramics.…”