When the true strain is 0.8 and deformation temperature is in the range of 1223~ 1323 K, full dynamic recrystallization occurs in the test steel at strain rate of 0.2~ 10 s~-1.The hot deformation activation energy Q of test steel is 289.9 kJ/ mol. 试验用钢在真应变为0.8,温度为1223~1323K,应变速率为0.2~10s-1的条件下,发生完全动态再结晶。