Improving deposition efficiency and inter-particle bonding of cold sprayed Cu through removing the surficial oxide scale of the feedstock powder
Improving deposition efficiency and inter-particle bonding of cold sprayed Cu through removing the surficial oxide scale of the feedstock powder
复制标题
通过去除原料粉末表面氧化皮提高冷喷涂Cu的沉积效率和颗粒间结合
DOI：
10.1016/j.surfcoat.2020.126709
复制
发表时间：
2021-02-15
影响因子：
5.4
通讯作者：
Li, Chang-Jiu
中科院分区：
文献类型：
--
作者：
Li, Yu-Juan;Luo, Xiao-Tao;Li, Chang-Jiu
在冷喷涂工艺中，原料粉末表面的氧化物氧化皮不仅降低了喷涂粉末的沉积效率，而且影响了颗粒间的结合，从而使存款层的性能恶化。为了同时提高喷涂粉末的沉积效率和存款层的性能，以铜为典型材料，采用酸洗方法去除原始粉末表面的氧化皮。在酸洗过程中，将铜粉颗粒浸入酸性醇溶液中，然后在低压罐中干燥。分别采用原始粉末和酸洗粉末作为喷涂粉末，在相同的喷涂条件下制备了铜镀层。系统研究了喷涂粉末的沉积行为、铜镀层的组织和性能，包括力学性能、导电性能和耐蚀性能。结果表明，酸洗可有效去除原始粉末表面的氧化皮，使粉末氧含量从0.12wt%降低到0.044wt%，从而使喷涂粉末的沉积效率从74%提高到84%。虽然这两种Cu沉积物都显示出致密的显微组织，从而显示出良好的抗腐蚀性，但Cu沉积物的拉伸性能和电导率随着喷涂粉末中氧含量的增加而降低，这对颗粒间结合敏感。采用酸洗粉末制备的铜存款层具有良好的上级拉伸性能和导电性能，抗拉强度为245 MPa，杨氏模量为85 GPa，电导率和热导率分别为90%IACS和298 W.m（-1）.K-1。因此，采用酸洗去除颗粒表面的氧化皮是提高喷涂粉末沉积效率，同时制备高性能冷喷涂金属存款层的有效途径。
In cold spray, surficial oxide scale of the feedstock powder not only reduces the deposition efficiency of spraying powder, but also deteriorates the properties of the deposit due to its influence on inter-particle bonding. To simultaneously improve the deposition efficiency of spraying powder and the properties of the deposit, in this study, taking Cu as a typical material, acid pickling was used to remove the oxide scale on the surface of the as-received powder. During acid pickling, Cu powder particles were immersed into the acid alcohol solution and then dried in a low-pressure tank. Using the as-received powder and acid-pickled powder as the spraying powder, Cu deposits were prepared under the same spraying conditions. The deposition behavior of spraying powders, the microstructure and properties, including mechanical properties, conductivities and anti-corrosion behavior of the Cu deposits were systematically studied. Results show that acid pickling can effectively remove the oxide scale on the surface of the as-received powder and reduce the powder oxygen content from 0.12 wt% to 0.044 wt%, leading to an increase in deposition efficiency of the spraying powder from 74% to 84%. Although both the Cu deposits reveal dense microstructure and thereby show good anti-corrosion, the tensile properties and conductivities of Cu deposits, which are sensitive to the inter-particle bonding, decrease with increase of the oxygen content in spray powder. Cu deposit prepared by acid-pickled powder shows the superior tensile properties and conductivities, and the tests yielded the tensile strength of 245 MPa, Young modulus of 85 GPa, electrical and thermal conductivities of 90%IACS and 298 W.m(-1).K-1. Therefore, it is an effective approach to improve the deposition efficiency of spraying powder and prepare high-property cold-sprayed metallic deposit simultaneously by using acid pickling to remove the surficial oxide scale of particle.