Tungsten carbide‑cobalt (WC-Co) thermal spray coatings are widely used for ambient temperature wear applications but are typically generated from feedstocks with 1–5 μm carbide particles rather than more desirable <1 μm carbide particles, due to challenges of carbide dissolution and carbon loss in-flight. This work explores a novel processing route for the WC-Co system that has been conceptually proven for the Cr₃C₂-NiCr system. The tendency for carbides to dissolve in-flight is maximised in this approach, with subsequent heat treatment used to precipitate submicron carbide particles. Part 1 of this two-part series assessed the theoretical feasibility of applying this concept to the Co-W-C system for WC-17wt%Co composites, and characterised high velocity oxygen fuel (HVOF), plasma Ar-He and plasma Ar-H₂ coatings. In this follow-up paper, the powder and coating samples were characterised by Differential Scanning Calorimetry (DSC), followed by heat treatments below and above the identified phase transition temperatures. Compositional and microstructural analysis led to identification of the reactions accounting for each of the DSC peaks. These observations were contrasted with theoretical predictions as a function of the extent of carbide dissolution/decomposition and carbon loss in the as-sprayed coatings.

碳化钨钴（WC-Co）热喷涂涂层广泛用于环境温度磨损应用，但由于碳化物溶解和溶解的挑战，通常由含1-5μm碳化物颗粒而不是更理想的<1μm碳化物颗粒的原料产生飞行中的碳损失。这项工作探索了一种针对WC-Co系统的新颖加工路线，该路线已在概念上证明了Cr ₃ C ₂-NiCr系统。在这种方法中，碳化物在飞行中的溶解趋势得以最大化，随后的热处理用于沉淀亚微米级碳化物颗粒。这个由两部分组成的系列文章的第1部分评估了将该概念应用于WC-17wt％Co复合材料的Co-WC系统的理论可行性，并对高速氧气燃料（HVOF），等离子Ar-He和等离子Ar-H _2进行了表征。涂料。在此后续论文中，粉末和涂料样品通过差示扫描量热法（DSC）进行表征，然后在确定的相变温度以下和之上进行热处理。组成和微观结构分析导致鉴定出每个DSC峰的反应。这些观察结果与理论预测相反，后者是喷涂涂层中碳化物溶解/分解程度和碳损失程度的函数。