基于内时大变形弹塑性本构模型的镦粗热力耦合分析

采用一个简单机械模型得到了热力耦合的弹塑性大变形本构方程,它满足不可逆热力学的基本约束,并考虑到了储存在残余微应力场中的能量对后续变形的贡献.发展了相应的算法,对弹性压板间的圆柱镦粗进行了分析.结果表明,在镦粗过程中的塑性耗散和工件两端的热传导造成工件中温度分布的不均匀,因此导致了材料力学性能的改变.与实验结果和等温假设下的计算结果进行了比较,表明计及塑性耗散热的计算结果与实验结果更为一致.

ENDOCHRONIC MODEL FOR COUPLED THERMAL-MECHANICAL PROBLEMS AND APPLICATION TO UPSETTING ANALYSIS

A thermomechanically consistent constitutive model for finite elastoplastic deformation was derived by using of a simple mechanical model,which satisfies the fundamental constraints of irreversible thermomechanics.The coupled temperature and deformation in upsetting processes were analyzed.It shows that the plastic deformation and the heat conduction results in a severe non-uniform temperature distribution,which may further lead to the change in the mechanical properties of the work-material.Comparison with the experimental results shows satisfactory agreement with each other.