The effects of hot isostatic pressing temperature and cooling rate on the microstructure of two powder metallurgy beta-gamma titanium aluminide alloys with nominal compositions TiAl-4Nb-3Mn (G1) and TiAl-2Nb-2Mo (G2) are investigated. Particular attention is placed on the volume fraction of the beta phase, which is known to improve the hot workability. The alloys are consolidated by hot isostatic pressing at 1200 °C, 1250 °C, and 1300 °C, and cooled at rates between 3.0 °C/min and 17.5 °C/min. The volume fraction of beta phase in both alloys was unaffected by the change in cooling rates. The volume fraction of the beta phase in G2 decreased linearly from ∼9.5 vol.% to ∼3.5 vol.% with increasing HIP temperature from 1200 °C to 1300 °C.

Additional Metadata
Keywords Beta phase, Hot isostatic pressing, Powder metallurgy, Titanium aluminide
Persistent URL dx.doi.org/10.4028/www.scientific.net/AMR.89-91.325
Citation
Laurin, D., Seo, D.Y., Saari, H, & Kim, Y.-W. (2010). The effects of hot isostatic pressing conditions on the microstructure of beta-gamma titanium aluminide powder alloys. doi:10.4028/www.scientific.net/AMR.89-91.325