玻璃态高聚物PMMA粘弹性力学行为的率温等效关系

THE RATE-TEMPERATURE EQUIVALENCE OF VISCOELAS-TIC BEHAVIOR FOR GLASSY POLYMER PMMA

摘要: 基于粘弹-塑性本构模型并以玻璃态高聚物PMMA在温度T=233—343K和应变率(?)=1.0 x 10~(-4)—1.0×10~(-1)s~(-1)范围内实测的应力-应变曲线及其拟合计算为依据,讨论了试验材料的率温等效性,从位移因子a_T和归一化应力-应变主曲线的存在,证实试验材料在屈服前存在率温等效关系,而在屈服后不复存在。

Abstract: The law of the strain-rate-temperature equivalence of PMMA up to yielding is discussed based on the viscoelastic/plastic constitutive model and experimental data of stress-strain curves at the range of T = 233-343K and ε=1.0×10-4-1.0×10-1s-1. The existence of the shifting factor ar and normalized stress-strain master curve shows the existence of strain-rate-tem. perature correspondence of PMMA before yielding.