Titanium materials are widely used in aviation; their poor wear resistance and easy high-temperature oxidation defects limit their further application. Cold spraying technology is an excellent way to solve these defects, has essential significance for its surface research. This study reports the deposition mechanism of Aluminium (Al) + Titanium (Ti) mixed powders deposited onto Ti6Al4V by cold spraying technology using Abaqus/Explicit. Because of its high surface hardness, it is not easy to obtain effective deposition by direct spraying with pure Al powder. Hence, Ti powder as the intermediate coating was proposed between Ti6Al4V and pure Al powder. Since there are few reports on numerical simulation of mixed particles, most studies focus on single or multi-particles of the same material. The critical process of numerical simulation of mixed powders is emphasized in detail. Using the recovery coefficient is defined to determine the critical speed. The results show that it is feasible to determine the critical velocity of mixed powder through the smaller value of recovery coefficient from the perspective of energy. In this paper, the recommended critical speed of mixed powder is 500 m/s–900 m/s. It will provide theoretical guidance for researchers and is of great significance to further expand the application of other mixed powders.