TC21 alloy was carried out on Gleeble–3800 thermal compression simulation tester at temperatures and strain rates ranging of 830–1010℃ and 0.0005–10s

–1

. Based on the compressed experimental data

taking the hot deformation constitutive relation model derivation of Arrhenius and the hot processing map construction under different instability criterion as the main line of the study

the constitutive model under different hot deformation parameters and the hot processing map under different instability criterion (Gegel

Malas

Prasad

Murty

Semiatin) were obtained. Then

the theoretical basis and prediction results of above five instability criterion were analyzed. By using the theory of hot processing map combining with microstructure

the suitable forming and flowing instability areas were p

redicted

and hot working processing parameters of TC21 alloy are optimized scientifically and rationally.