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

二零一九财政年度致力于精细不锈钢金属玻璃粉末。为了将它们用于冷喷涂，以实验室规模制备大量（约3 kg）。X射线衍射证实了矿石的玻璃态。矿石的雾化工作承包给了一家公司.要求粒度分布在约20-30微米，并通过激光散射粒度测定法确认。记录X射线衍射图以检查玻璃态。SEM观察结果显示了适用于冷喷涂的球形和细长颗粒的混合物。进行了高压冷喷涂沉积。通过添加分散剂解决了颗粒的团聚。然而，由于冷喷涂装置所允许的最高温度，无法实现高沉积速率，因此，采用放电等离子烧结法制备金属玻璃样品。结果表明，升温速率对结晶度有直接影响，但降低了致密化程度。第一篇论文讨论了这一点和这些材料的耐腐蚀性。陶瓷颗粒也加入到SPS样品中。实现了更高的密度，因为金属玻璃颗粒之间的空隙也被陶瓷填充。进行了磨损测试，第二篇论文正在考虑中。

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.