Cold Spray Additive Manufacturing of Al/Diamond Composites Using Core-Shell-Structured Diamond

In this work, advanced Al/diamond wear-resistance composites were fabricated by solid-state cold spray additive manufacturing using core-shell-structured diamond powders. Based on the experimental results and thorough discussion, it is found that core-shell-structured diamond powders were much easier to deposit than pure Al by cold spray, showing great potentials as feedstock for cold spraying. The deposition mechanism of the Al/diamond composites were dominated by the true metallic bonding between Al matrix and Cu layer, which is different from other conventual cold sprayed metal matrix composites. Tensile tests indicated that the tensile strength of the Al/diamond composites can be higher than cold sprayed pure Al. In addition, the Al/diamond composites had super wear-resistance performance. The wear rate was reduced by 17.8 times for the N_4-1 composite and by 37.5 times for the N_1-1 composite as compared with cold sprayed Al/Al₂O₃ composite.