ABSTRACT Ultrasonic surface shot peening (USSP) treatment was conducted on the WC-8Co composite. The effects of different USSP-treated time on surface roughness, microstructure, mechanical and corrosion resistance were investigated. The results show that continuous bombardment on the surface of WC-8Co cemented carbide induced by high kinetic energy particles during USSP makes the WC particles and Co phase broken and refined. A nanostructured layer is generated on the top-surface of WC-Co cemented carbide and the thickness is about 3.14 µm. Due to the polishing and washing of all samples, the results of surface roughness don’t change much. Microhardness of nanostructured surface layer increases by 15.8% compared with the untreated sample. Electrochemical experiment results indicated that the refinement of grain are the main reasons for the enhanced corrosion behavior of the samples. At the same time, the most suitable shot peening time of USSP for WC-8Co cemented carbide is 30 min.

中文翻译：

---

WC-Co合金超声喷丸强化实验研究

摘要 对 WC-8Co 复合材料进行了超声波表面喷丸硬化 (USSP) 处理。研究了不同 USSP 处理时间对表面粗糙度、微观结构、机械和耐腐蚀性能的影响。结果表明，USSP过程中高动能粒子对WC-8Co硬质合金表面的连续轰击使WC粒子和Co相破碎细化。在 WC-Co 硬质合金的顶面生成纳米结构层，厚度约为 3.14 µm。由于所有样品都经过抛光和清洗，表面粗糙度的结果变化不大。与未经处理的样品相比，纳米结构表面层的显微硬度增加了 15.8%。电化学实验结果表明，晶粒细化是试样腐蚀行为增强的主要原因。同时，USSP对WC-8Co硬质合金最合适的喷丸时间为30分钟。