Variation of Hardness with Microstructure Evolutions in Metastable β Titanium Alloy TIMETAL®LCB
Microstructure evolutions and hardness variation during aging in metastable β titanium alloy TIMETAL®LCB have been examined. In as-quenched specimen after solution treatment, athermal ω phase formed. Isothermal ω phase formed during aging at 623 K, and α phase formed after precipitation of isothermal ω phase during aging at 673 and 773 K. Alpha phase nucleated at isothermal ω phase, and had the orientation relationship with β and ω, (111)β//(0001)ω//(1120 )α and [10 1 ]β//[1120 ]ω//α . During aging at 873 K, α phase formed without isothermal ω phase. Hardness increased with increasing aging time and decreasing aging temperature, partly because number density of isothermal ω or α precipitates increased with increasing aging time and decreasing aging temperature.
Young Won Chang, Nack J. Kim and Chong Soo Lee
T. Sakamoto et al., "Variation of Hardness with Microstructure Evolutions in Metastable β Titanium Alloy TIMETAL®LCB", Materials Science Forum, Vols. 561-565, pp. 2067-2070, 2007