Corrosion-wear mitigation: are metallic glass coating deposited by cold spray good candidates?

FY2019专注于精密不锈钢金属玻璃粉末。为了将它们用于冷喷雾，在实验室规模上制造了大量（约3公斤）。用x射线衍射证实了矿石的玻璃态。矿石的雾化工作外包给了一家公司。用激光散射粒度法确定了20 ~ 30微米左右的粒度分布。记录x射线衍射图以检查玻璃态。扫描电镜观察显示适合冷喷涂的球形和细长颗粒混合。进行了高压冷喷涂沉积。加入分散剂可解决颗粒团聚问题。然而，由于冷喷涂装置允许的最高温度，没有达到高沉积速率。为此，采用火花等离子烧结法制备了金属玻璃样品。结果表明，升温速率对结晶性有直接影响，但降低了致密性。第一篇书面论文论述了这一点以及这些材料的耐腐蚀性。SPS样品中还添加了陶瓷颗粒。由于金属玻璃颗粒之间的空隙也被陶瓷填充，因此实现了更高的密度。进行了磨损试验，目前正在审议第二篇论文。

FY2019 was dedicated to elaborate stainless steel metal glass powders. In order to use them for Cold spray, a large quantity (at about 3 kg) was made at the lab scale. The glassy state of ores was confirmed by X-ray diffraction. Atomisation of ores was contracted out a company. Size distribution at about 20-30 micronmeter was requested and confirmed by laser scattering granulometry. X-ray diffraction patterns were recorded to check the glassy state. SEM observations shown a mix of spherical and elongated particles suitable of cold spray.FY2020. High pressure cold spray deposition were performed. Agglomeration of particles was solved by a dispersant addition. However high deposition rate was no achieved because of maximum temperature allowed by cold spray setup.Therefore, Metallic glass samples were produced by Spark Plasma Sintering. The results show that the heating rate has a direct effect on the crystallinity but reduces the densification. A first paper in writting deals with this point and the corrosion resistance of these materials.Ceramic particles were also added to SPS samples. Higher density were achieved because the voids between metal glass particules was also filled by the ceramic. Wear tests were carried out and a second paper is under consideration.