【摘要】 应用 GLEEBLE- 1 50 0热模拟试验机测量了 0 .95C- 1 8W- 4Cr- 1 V高速钢的应力 -应变曲线 ,由此得到加工硬化率 -应变关系曲线 ,从而确定发生动态再结晶后的稳态应变 εs.稳态应变随着变形温度的升高和应变速率的降低而下降 ;且随着应变速率的增加 ,温度的变化对稳态应变的影响逐渐减小 .Zener- Holloman参数 Z的变化对动态再结晶的临界应变影响较小 ,而对稳态应变的影响较大 .回归分析得到 0 .95C- 1 8W- 4Cr- 1 V高速钢的动态再结晶的晶粒尺寸和体积分数的数学模型 :Ddyn=1 .2 7× 1 0 3Z-0 .16,F=1 - exp - 2 .8ε-εcεs-εc1.7.更多还原

【Abstract】 The stress σ -strain ε curves of 0.95C 18W 4Cr 1V high speed steel were measured during hot deformation with GLEEBLE 1500 thermal simulator. With working hardening rate θ -strain ε curves, which are deduced from the stress-strain curves, the static strain ε s was determined. It is found that the values of static strain decrease with the increase of deformed temperature and the decrease of strain rate, and the influence of variation temperature on static strain weakens as the strain rate increases. The effect of Zener Holloman parameter Z on the static strain is significant but that on the critical strain ε c is not so large . The mathematic model for dynamic recrystallization of 0.95C 18W 4Cr 1V high speed streel was obtained with regression. The grain size D dyn and the volume fraction F after the dynamic recrystallization are: D dyn =1.27×10 3 Z -0.16 , F =1-exp-2.8 ε - ε c ε s- ε c 1.7 .更多还原