摘要:
不同应用场景对粉体材料的性能需求各不相同，而粉体的基本特性主要由其制粉工艺决定。NiCoCrAlY是一种性能优异的镍基高温合金粉末，广泛应用于增材制造、激光熔覆、喷涂涂层及粉末冶金等领域。基于当前主要的粉体制备技术，本文探讨了等离子旋转电极法、真空气雾化法和团聚烧结法对NiCoCrAlY粉末粒形、粒径、孔隙率及氧含量等基本特性的影响。研究结果表明，等离子旋转电极法制备的粉末粒形最为规则，粒径分布最为集中，且氧含量和孔隙率最低，非常适用于高精度增材制造和高性能涂层制备；真空气雾化法制备的粉末粒径均匀性较好，但存在少量非球形颗粒，氧含量和孔隙率略高，较适用于大规模工业应用；团聚烧结法制备的粉末孔隙率适中，但粒径分布不均，氧含量极高，仅适用于对粉体质量要求不高且注重成本控制的领域，如大粒径粉末或复合粉末的制备。本研究旨在为面向具体应用需求合理选择及进一步优化NiCoCrAlY粉体制备工艺提供一定参考。
Abstract:
The specific requirements of powder materials depend on the service environments. However, the fundamental characteristics of powders are primarily determined by manufacturing processes. As a high-performance nickel-based superalloy powder, NiCoCrAlY has been widely used in the additive manufacturing, laser cladding, thermal spray coatings, and powder metallurgy. Based on the major powder production techniques, this study investigated the effects of plasma rotating electrode process (PREP), vacuum gas atomization (VGA), and agglomeration-sintering methods on the basic characteristics of NiCoCrAlY powders, including the particle shape, particle size, porosity, and oxygen content. The results indicated that powders prepared by the plasma rotating electrode process exhibited the most regular particle shape, the best distribution of particle size, and the lowest oxygen content and porosity, making them highly suitable for the high-precision additive manufacturing and high-performance coatings. Powders produced by the vacuum gas atomization showed a relatively uniform particle size but contained a small fraction of non-spherical particles. The oxygen content and porosity were slightly higher, making them more suitable for large-scale industrial applications. In comparison, powders produced by the agglomeration-sintering exhibited a moderate porosity but a strikingly uneven distribution of particle size and an extremely high oxygen content, putting their applications only in where low-quality requirements and the cost control are prioritized, such as the production of large-particle powders or composite powders. This study aimed to provide a reference for the rational selection and further optimization of NiCoCrAlY powder production techniques based on specific application requirements.
百度学术
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