【摘要】 用Thermecmaster-Z热模拟试验机试验得出成分为0.006 7%C-0.045 0%Ti的Ti-IF(无间隙原子)钢在变形温度750~900℃和变形速率0.1~40 s-1时的应力-应变曲线,确定了Zener-Holloman参数Z与应变速率.ε和温度T(K)的关系式Z=.εexp(39 507/T),并建立了临界应变εc与原始晶粒尺寸d0和Z参数的临界应变方程εc=2.314 4×10-3×d00.803 9×Z0.050。结果表明,在相同变形速率下,850℃变形时动态再结晶最易发生,当变形温度提高至900℃(两相区)时,即使在低变形速率(1 s-1),也不发生动态再结晶。当变形速率大于1 s-1时,Ti-IF钢热加工时不能出现动态再结晶。临界应变预测值与实测值比较,平均误差≤5%。更多还原

【Abstract】 The stress-strain curves of（0.006 7）C-（0.045 0）Ti Ti-IF（interstitial free） steel with deformation temperature 750～900 ℃ and deformation rate 0.1～40 s^-1 has been tested and obtained by Thermecmaster-Z thermal simulation test machine,based on that the relational expression between Zener-Holloman parameter Z and deformation rate(ε[DD（-*3]·）-temperature T（K）: Z=(ε[DD（-*3]·） exp（（39 507）/T） is defined,and the critical strain formula for relation between critical strain ε_c and original grain size d₀-Z parameter: ε_c =（2.314 4）×10^-3×d^{0.803 9}₀×Z^0.050 is established.The results showed that with same deformation rate the dynamic recrystallization of steel occurred most easily at 850 ℃,as deformation temperature increased to 900 ℃（dual phase region）,the dynamic recrystallization un-occurred even at low deformation rate(1 s^-1),and as deformation rate was more than 10 s^-1, the dynamic recrystallization of Ti-IF steel also un-occurred during hot rolling.With comparison between predicted value of critical strain and measured value,the average error was no more than 5%.更多还原