화학공학소재연구정보센터
Powder Technology, Vol.283, 9-15, 2015
Fabrication of micro-fine spherical high Nb containing TiAl alloy powder based on reaction synthesis and RF plasma spheroidization
A compact process for fabricating micro-fine spherical TiAl-Nb alloy powders was developed with a combination of reaction synthesis and plasma spheroidization technique. Powders of TiH2, Al and Nb were firstly mixed and refined by high-energy ball milling, and the mixture was then heated at different temperatures ranging from 600 to 1200 degrees C for 2 h, allowing synthesis reaction to take place. Ultimately, the synthesized powders melt through radio frequency (RF) argon plasma and rapidly solidified into micro-fine spherical TiAl-Nb alloy powders. The fabrication process and powder characteristics were investigated. With the process described above, the alloy powders with high composition homogeneity and good sphericity can be fabricated. The obtained spherical powders perform a uniform equiaxed-grain microstructure dominated by a supersaturated alpha(2)-Ti3Al phase. The powders possess a micro-fine average particle size of 9.6 mu m, with a distribution uniformity level of 0.622. (C) 2015 Elsevier B.V. All rights reserved.