摘要
本文从非线性粘弹性物质的多重积分型本构方程出发,引入塑性应变,推导了粘弹塑性物质的微分型本构方程.进一步考虑材料的损伤特性,建立了泡沫塑料包装衬垫的缓冲性能模型.根据在一种跌落高度、衬垫厚度和静态应力组合条件下的国产可发聚苯乙烯沫泡塑料的连续多次跌落冲击试验数据,识别了其缓冲性能模型参数.动力学计算与试验结果的比较表明,该模型能较好地反映可发聚苯乙烯泡沫塑料包装衬垫在连续多次跌落冲击过程中的加速度、速度、位移变化,冲击能量的吸收性和塑性变形等基本特性.并且仅根据在一种组合条件下的试验数据所识别的这一模型,在其它组合条件下其缓冲性能与试验结果也吻合较好.
Introducing the plastic strain the differential constitutive equation for viscoelastic and plastic materials is deduced from multi-integral constitutive equation for nonlinear viscoelastic materials.The dynamic cushioning performance model of expanded plastics cushions in shockproof packaging is constructed based on the differential constitutive equation for viscoelastic and plastic materials and considering the breakage character of materials.The parameters of the model of expanded polystyrene made in China are identified according to the experimental data in serial drop-type shock tests under one composite condition of drop height,cushion thickness and static stress.The comparing of dynamic calculation results with testing results expresses that the model can reflect the fundamental dynamic characters such as the variations of acceleration,velocity and displacement,the plastic deformation of cushion and so on well.The dynamic cushioning performances of the model can also fit testing results under other
composite conditions.
出处
《振动工程学报》
EI
CSCD
1990年第3期9-17,共9页
Journal of Vibration Engineering
关键词
包装
泡沫塑料
衬垫
缓冲性能
viscoelasticity
viscoplasticity
constitutive equations
model of dynamic cushioning performances
drop-type shock
