Sintering of gamma Titanium Aluminide (TiAl) Alloys Aided by Small Additions of Copper
Titanium aluminide alloy powders are difficult to sinter unless assisted with pressure. This investigation explores the use of sintering aids to enable pressureless sintering of Ti-48Al-2Cr-2Nb in order to take advantage of the conventional powder metallurgy (PM) approach for low-cost near-net shape fabrication. Thermodynamic calculations using ThermoCalc and Ti-alloys database TTTI3 predict that copper (Cu) is a potential sintering aid for Ti-48Al-2Cr2Nb. The effect of Cu additions from 0 to 2 at. ％ on the sintering of Ti-48Al-2Cr-2Nb was accordingly assessed at 1375C with 120 min isothermal holding in vacuum. The sintered density increased from (73. 9 ± 0. 6)％ theoretical density (TD) without Cu to > (98 ± 0. 5) ％TD with an addition of 2 at. ％Cu,demonstrating the significant effectiveness of Cu as a sintering aid for Ti-48Al-2Cr-2Nb. The enhanced densification is attributed to liquid formation. A minor Cu- and Crenriched phase was detected with additions of ≥1. 0 at. ％Cu. The as-sintered microstructures and phase constituents were analysed by scanning electron microscopy equipped with an Energy Dispersive Spectroscopy (EDS) microanalysis system and X-ray diffraction analysis.
Titanium aluminide powder metallurgy. Sintering aids copper
Y. Xia G. B. Schaffer M. Qian
The University of Queensland, School of Mechanical and Mining Engineering, ARC Centre of Excellence for Design in Light Metals,Brisbane,QLD4072 ,Australia
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
1398-1401
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）