Microstructural Properties of Air Plasma Sprayed Coating Consisting of Tungsten Carbide and Yttria‐Stabilized Zirconia

Abstract

Thermal Spraying technologies are proven to be capable of producing composite materials and structures. In the present work, an innovative composite coating was produced to achieve high wear and thermal resistant properties in a single‐step process using air plasma spraying (APS) technique. Tungsten carbide has shown high wear resistance and zirconia coatings exhibited excellent tribological and insulation properties. It is speculated that a composite material consisting of zirconia and tungsten carbide exhibits excellent thermomechanical properties. A powder mixture of 50wt% WC‐10wt% Ni (WC‐Ni) and 50wt% ZrO2‐8wt% Y2O3 (YPSZ) was deposited on a low carbon steel substrate using APS technique. Important microstructural properties of WC‐Ni/YPSZ coating such as splat boundaries, pore and grain morphology, microcracks, phase composition, elemental distribution of coatings, and lattice parameters of the crystals were investigated using optical microscopy, scanning electron microscopy (SEM), energy dispersive X‐ray (EDS), and X‐ray diffractometry (XRD). A good adhesion was observed between different phases in tungsten carbide mixed with zirconia coatings. Decarburization process which occurred during APS process resulted in formation of tungsten hemi‐carbide (W2C) phase in plasma sprayed samples. The calculated crystal size for APS‐deposited coating was smaller than those of feedstock powder.

Effect of volume fraction of reinforcement phase on mechanical behavior of ultra-high-temperature composite consisting of iron matrix and TiB2 particulates

“…Indentations were made at enough distance from each other to avoid the interaction of indentations on each other. 42,43 Compression tests were also conducted on P/M processed samples to determine the mechanical properties such as Young’s modulus, yield strength, and ultimate compression strength. Five cylindrical compression test samples with aspect ratio of 2:1 (Ø: 10 cm, H: 20 cm) were fabricated and tested according to ASTM E9-09 standard for each group of P/M samples.…”

High temperature corrosion and electrochemical behavior of HVOF sprayed Inconel 718 coating using an innovative device: HTCMD

“…The sample preparation procedure for microstructural characterization was mentioned in the author's previous work . Inconel 718 coated sample was prepared accordingly and its microstructure was studied by scanning electron microscopy (SEM) using a JEOL JSM‐6490LV scanning electron microscope (JEOL USA, Inc., Peabody, MA).…”

“…The most common fuel gases used in this process are propane, propylene, and acetylene. HVOF technology is capable of generating very dense coating with less oxidized particles, compared to the other thermal spray techniques . Providing high density, smoother surface finish, low oxide level and porosity, less effect of environment during the spraying process, and consequently better corrosion and wear resistance properties, made HVOF as a promising and highly acceptable process for metal‐based coating deposition …”

Evaluation of solid particle erosion and electrochemical corrosion of plasma-sprayed WC/8YSZ coating on SS316

“…Electrochemical corrosion tests were carried out on the coated surfaces in potentiostat/galvanostat devices (ACM Instruments GillAC, UK) in compliance with Microcracks are discovered due to a mismatch in the thermal coefficients of the components in the coating [11]. The higher temperature associated with the plasma jet can cause carbide breakdown or severe oxidation when spraying in the air.…”

“…Galedari et al [11] prepared a composite coating consisting of 50wt%WC-Ni and 50 wt% ZrO 2 -Y 2 O 3 and applied it on low carbon steel. The results highlighted that the ZrO 2 had shown remarkable tribological characteristics and the presence of WC has resulted in high wear resistance.…”