喷雾造粒预合金化W-Ni-Fe三元合金粉末及射频热等离子体致密球化研究

Research on the Spray Granulation Pre-Alloyed W-Ni-Fe Ternary Powder and Densification and Spheroidization by RF Thermal plasmas

摘要:

球形致密化的钨基（W-Ni-Fe）合金粉末对增材制造等粉末成形构件的强度等物理性能的提升具有重要意义。采用喷雾造粒和射频热等离子体高温致密球化处理的方式研究了W-Ni-Fe粉末经喷雾造粒后射频热等离子体处理对其合金粉末的形貌、孔隙等的作用效果。研究表明，经喷雾造粒后所形成的96W-2.5Ni-1.5Fe三元合金粉末显微组织结构疏松，内部中空洞较多且表面粗糙；射频热等离子体对喷雾造粒粉进行处理后其综合性能提高，球形粉表面孔洞及疏松现象有所缓解，但仍有部分颗粒表面与内部存在微孔，且致密球化后的W晶粒之间Ni、Fe相含有较高含量的W元素。

Abstract:

The Spherical and densified of tungsten-based (W-Ni-Fe) alloy powder is of great significance to the improvement of physical properties such as the strength of powder-formed components for additive manufacturing. The effects of spray granulation and radio frequency (RF) thermal plasma treatment on the morphology and porosity of W-Ni-Fe alloy powder were studied by the spray granulation and radio frequency thermal plasma densification and spheroidization with high temperature. The research shows that the 96W-2.5Ni-1.5Fe ternary alloy powder formed by spray granulation has a loose microstructure, many internal voids and a rough surface. The comprehensive properties of the spray granulated powder can be significantly improved after the radio frequency thermal plasma treatment. The holes and looseness on the surface of spherical powder are alleviated, but there are also some micropores on the surface and internal with a few particles. The Ni and Fe phases between the W grains of the densified and spheroidized particles contain a relatively high content of W element.