A new method, called pressure gas atomization, capable of producing metal powder with a narrow size distribution, small size and spherical shape is presented. The employed pressure-gas atomizer combines a pressure-swirl nozzle, which produces a liquid hollow-cone-film, and a ring-gas nozzle to atomize the ligaments and/or the droplets of the film. The relationship between gas flow and spray angle are investigated. An enlarged hollow-cone film resulted from an increased gas mass flow. Besides the larger amount of energy provided by the increased gas mass flow, the widening of the hollow cone causes the atomization zone to be moved closer towards the gas nozzle. This leads to a reduction in particle size. The breakup of the film is visualized with video recording and high speed photography. Laser diffraction and image analysis are used to measure the size distribution of metal powder. The process parameters: molten metal mass flow (160-190 kg/h), gas mass flow (40-225 kg/h) and the geometry of the atomizer are varied.
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机译：呈现了一种新的方法，称为压力气体雾化，能够产生具有窄尺寸分布，小尺寸和球形的金属粉末。所用的压力气体雾化器结合了一种压力 - 旋流喷嘴，其产生液体中空锥膜，以及环 - 气体喷嘴，以雾化膜的韧带和/或薄膜的液滴。研究了气流和喷射角之间的关系。扩大的空心膜膜由增加的气体质量流量产生。除了由增加的气体质量流量提供的较大量之外，中空锥体的加宽导致雾化区朝向气体喷嘴移动更靠近。这导致粒度的降低。通过视频录制和高速摄影可视化电影的分解。激光衍射和图像分析用于测量金属粉末的尺寸分布。工艺参数：熔融金属质量流量（160-190 kg / h），气体质量流量（40-225 kg / h）和雾化器的几何形状变化。
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