热处理对冷喷涂Fe涂层组织与性能影响研究

冷喷涂作为一种新型的涂层技术,在制备大部分金属涂层、金属陶瓷复合涂层方面有着巨大的潜力。本文采用冷喷涂在Al基体上制备了Fe涂层,并结合喷涂后热处理研究了涂层组织与性能特点。结果表明,所得Fe涂层的内部组织比较致密;受到喷涂过程中空气的影响,喷涂射流呈现亮流,所制备涂层表面有较大、较深气孔。在较低温度下热处理后Fe涂层的显微组织变化不明显,显微硬度明显降低;Fe涂层与Al基体之间形成约10μm厚度的金属间化合物层。

Effect of Heat Treatment on Microstructure and Properties of Cold Sprayed Iron Coating

Cold spraying has great potentials in deposition of a majority of metallic coatings and metal-ceramic composites for many industry applications. In this study, iron coatings were deposited on aluminum substrates and the effect of post-spray heat treatment on the coating microstructure and microhardness was examined. The results showe that the as-sprayed Fe coating presents a relatively dense inner structure but a relatively porous top layer. Some large open pores were present on the coating surface due to the influence of in-flight particle surface oxidation which was observed as the bright spray jet during spraying. The microstructure of the annealed Fe coating changed little, but the coating microhardness was decreased significantly. The intermetallics of 10μm thickness were formed between the Fe coating and Al substrate.