Thermal spraying has become an industrial standard in the production of wear-resistant WC-Co and Cr₃C₂-NiCr composite coatings. However, generating optimum wear-resistant nano-reinforced carbide microstructures within the coatings remains challenging. The alternative two-step approach in this work involves coating formation under high energy conditions to generate maximum carbide dissolution, followed by heat treatment to precipitate nanocarbides. Microwave heating of particulate materials has been reported to offer several benefits over conventional furnace heating, including faster heating rates, internal rather than external heating, and acceleration of reactions/phase transformations at lower temperatures. This novel work explored the use of microwaves for heat treatment (as distinct from melting) of WC-Co and Cr₃C₂-NiCr thermal spray coatings and contrasted the rate of phase development with that from conventional furnace treatment. Coatings were successfully microwave heat-treated to generate the same phase composition as furnace treatment. Both treatments generated comparable results in the Cr₃C₂-NiCr system. The WC-Co system achieved a much more crystalline structure in a dramatically shorter time relative to the conventional furnace-treated sample. The results are contrasted as a function of material and microstructure interaction with microwaves and the critical phase transition temperatures to account for the observed responses.

热喷涂已成为生产耐磨WC-Co和Cr ₃ C ₂ -NiCr复合涂层的工业标准。然而，在涂层内生成最佳的耐磨纳米强化碳化物微观结构仍然具有挑战性。这项工作中的替代两步方法包括在高能条件下形成涂层，以产生最大程度的碳化物溶解，然后进行热处理以沉淀纳米碳化物。据报道，颗粒材料的微波加热比传统炉加热具有多种优点，包括更快的加热速率、内部加热而不是外部加热以及在较低温度下加速反应/相变。这项新颖的工作探索了使用微波对 WC-Co 和 Cr ₃ C ₂ -NiCr 热喷涂涂层进行热处理（与熔化不同），并将相发展速率与传统炉处理的相发展速率进行了对比。涂层成功地进行了微波热处理，产生与炉处理相同的相组成。两种处理在 Cr ₃ C ₂ -NiCr 系统中产生了类似的结果。与传统炉处理样品相比，WC-Co 系统在更短的时间内获得了更多的晶体结构。将结果作为材料和微观结构与微波相互作用的函数以及临界相变温度进行对比，以解释观察到的响应。