Hot Deformation Studies on beta(0) Stabilized TiAl Alloy Made Through Ingot Metallurgy Route

Artikel i vetenskaplig tidskrift, 2021

Hot deformation studies of a newly designed gamma + alpha(2) based TiAl alloy of composition Ti-42Al-6Nb-3Cr-0.1B at.% (nominal) realized through ingot metallurgy route using double vacuum arc remelting were carried out. Hot isothermal compression testing was performed in Gleeble (TM) 3500 at different temperatures ranging from 1123 to 1373 K at 50 K intervals and strain rates of 0.001-1 s(-1). Processing maps were developed using an approach of dynamic material modeling of the flow curves to establish the safe hot working regime. Strain rate sensitivity and Zener-Holloman parameters were calculated and constitutive equation was derived. Microstructural investigation revealed dynamic recrystallization and activation of multiple twin systems as the main softening mechanisms operating at optimum hot working conditions. Safe hot working temperature and strain rate regime for the alloy was found to be in the temperature range of 1323-1373 K and strain rate range of 0.001-0.01 s(-1).