【摘要】 利用Gleeble 3500热模拟试验机对中碳钢淬火和完全退火组织的温加工流变应力在不同的变形参数条件下进行了对比研究,并根据其真σ-ε曲线拟合了可反映该材料两种原始状态下压缩的稳态流变曲线和变形参数之间关系的中温压缩变形本构方程。结果表明:当.ε为0.01 s-1时,室温压缩的σ-ε曲线,淬火态的远高于退火态;350~550℃压缩,淬火态稍高于退火态;高于600℃压缩,淬火态的流变应力在变形初期略高于退火态,随应变的增加,淬火组织的流变曲线低于退火组织;在压缩温度为650℃,.ε为1 s-1、0.1 s-1、0.01 s-1时,淬火和退火组织压缩的σ-ε曲线有交点,在.ε为0.001 s-1时,淬火组织的σ-ε曲线低于退火组织的σ-ε曲线。更多还原

【Abstract】 A comparative study of warm flow stresses of the as-quenched and the as-annealed samples from a medium carbon steel was conducted by using a Gleeble3500 heat-analogue machine.And the constitutive equations for warm deformation were obtained through the analysis of simulated σ-ε curves under various warm deformation conditions.The results show that,when deformed at room temperature and strain rate,,was 0.01 s-1,the flow stress of the as-quenched sample was much higher than that of the as-annealed sample.For deformed at 350 ℃,the σ-ε curves of the as-quenched sample is still higher.For compression at or above 600 ℃ with was 1 s-1,0.1 s-1 and 0.01 s-1,a critical strain was found,after the critical strain,the flow stress of the as-quenched sample is lower than that of the as-annealed one.It should be noted that,when deformed at 650 ℃ with of 0.001 s-1,the whole flow curve of the as-quenched sample was lower than that of as-annealed one.更多还原