Research Advances in Close-Coupled Atomizer Flow and Atomizing Mechanisms

As component manufacturing technology evolves, more demands are placed on improved performance of metal/alloy powders in medical, military, machining, and 3D printing applications. High-quality powders are characterized by low oxygen content, precise alloy composition, small particle size, and high particle sphericity. Coupled gas atomization powder preparation technology is an ideal choice for preparing high-quality powders with high atomization efficiency, low oxygen content, and high cooling rate. However, this powder preparation technology’s multiphase flow and multiscale coupling is a complicated physical process. In addition, the mechanism of atomization has not yet been fully understood. Thus, there is no consensus on the atomization phenomena and atomization mechanisms. Close-coupled gas atomization powder preparation technology is facing great challenges in the field of low-cost mass production of high-quality powders. Therefore, it is expected to improve the close-coupled gas atomized powder preparation technology and achieve breakthroughs in atomization principle, such as high-efficiency gas atomization technology, intelligent control of the high-efficiency gas atomization process, and so on. In this respect, this review summarizes the atomizer structures, gas atomization flow field-testing technologies, and gas atomization flow field numerical simulations based on relevant literature. In addition, the gas atomization mechanism of the closely coupled atomizers will be analyzed. Finally, several research directions are proposed for further in-depth studies on the atomization characteristics and mechanisms of close-coupled vortex loop slit atomizers.