The deformation behaviour of particles and substrate in cold spray is dictated by the intrinsic properties of both materials, and their bonding directly affects the resulting properties of the deposited coating. The processing through heat treatment of aluminium alloy powders has only recently been developed for both cold spray and additive manufacturing, hence the necessity to evaluate and further understand the evolution of their properties. In this study, an Al 7075 gas-atomised powder was solution heat treated, quenched and subsequently aged. The powder in its as-quenched, T4 (natural ageing at room temperature for 21 days) and T6 (artificial ageing at 120 C for 24 h) condition was characterised through differential scanning calorimetry and scanning electron microscopy to evaluate the precipitation kinetics. Powders were cold sprayed using heated N₂ at 500 C and 6.0 MPa and the resulting deposits were evaluated using tubular coating tensile and pull-off bond strength tests. The precipitation development in the gas atomised powder was found to be similar to the bulk alloys, with development of η′ precipitates during artificial ageing and Guinier-Preston zone formation and development during natural ageing. A relationship between the deposition efficiency of the powders and the coating properties was discovered and explained through an adapted densification mechanism based on powder tamping.

两种材料的固有特性决定了冷喷涂中颗粒和基材的变形行为，它们的结合直接影响到沉积涂层的最终性能。铝合金粉末的热处理工艺直到最近才被开发用于冷喷涂和增材制造，因此有必要评估和进一步了解其性能演变。在这项研究中，对Al 7075气雾化粉末进行了固溶热处理，淬火并随后进行了时效处理。通过差示扫描量热法和扫描电子显微镜对处于急冷状态的粉末T4（室温下自然老化21天）和T6（120℃下人工老化24小时）进行了表征，以评估沉淀动力学。在500℃和6.0 MPa下的压力为₂，并且使用管状涂层拉伸和剥离粘合强度测试评估了生成的沉积物。发现在气体雾化粉末中的沉淀发展与块状合金相似，在人工时效过程中η'沉淀的发展以及在自然时效过程中吉尼尔-普雷斯顿区的形成和发展。通过基于粉末夯实的适应性致密化机理，发现并解释了粉末的沉积效率与涂层性能之间的关系。