Withdrawn: Research progresses in flow field of close-coupled atomizer and atomization mechanism

With the development of part manufacturing technology, many fields, such as medical treatment, military industry, machine and three-dimensional (3D) printing, propose increasingly higher requirements on performances of metal/alloy powder. Low oxygen content, accurate alloy composition, small particle size and high particle sphericity become characteristics of high-quality powder. With high atomization efficiency, low oxygen content in powder and high cooling rate, the close-coupled gas atomized powder preparation technology is an ideal choice to prepare high-quality powder. Nevertheless, powder preparation technology based on close-coupled gas atomization is a complicated process with mutual coupling effects of multiple-phases flows. However, the atomization mechanism still is not revealed fully yet. Close-coupled gas atomized powder preparation technology is facing with great challenges in mass preparation of high-quality powders at a low cost. It is expected to improve close-coupled gas atomized powder preparation technology and even achieve breakthroughs in atomizing principle. For this reason, this study summarized atomizer structure, gas atomization flow field test technology and gas flow field numerical simulation thoroughly according to existing associate studies. Moreover, the gas atomization mechanism of close-coupled atomizer was analyzed. Finally, further deep studies on atomizing characteristics and atomization mechanism of close-coupled vortical loop slit atomizer were prospected and several research directions were proposed.