Strain Rate Dependence of Compressive Stress-Strain Loops of Several Polymers
Strain Rate Dependence of Compressive Stress-Strain Loops of Several Polymers
复制标题
几种聚合物的压缩应力-应变环的应变率依赖性
DOI：
10.1299/jmmp.2.557
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
T. Yokoyama
中科院分区：
文献类型：
--
作者：
K. Nakai;T. Yokoyama
在标准分离式霍普金森压杆上测定了几种商品聚合物在近700/S应变率下的压缩应力-应变曲线。四种不同的聚合物或典型的热塑性塑料：ABS、PA-6、PA-66和PC在室温下进行了测试。长细比(=高L/直径d)为0.5的圆柱体试件用于霍普金森杆试验，静力试验采用ASTM规范E9-89a中规定的L/d=1.5的圆柱体试件。在Instron试验机上测量了低应变率和中等应变率下的压缩应力-应变曲线。研究了应变率对弹性模量、2.5%流动应力和耗散能的影响。结果表明，随着应变率的增加和应变的增加，应力-应变环内的面积(或耗散能)增大，即所有受试聚合物都表现出本征的动态粘弹性和完全卸载后的高弹性后效。
The compressive stress-strain loops of several commercial polymers at strain rates of nearly 700/s are determined in the standard split Hopkinson pressure bar. Four different polymers or typical thermoplastics: ABS, PA-6, PA-66 and PC are tested at room temperature. Cylindrical specimens with a slenderness ratio (= height l /diameter d) of 0.5 are used in the Hopkinson bar tests, and those with l/d = 1.5 as specified in the ASTM Designation E9-89a are used in the static tests. The stress-strain loops in compression at low and intermediate strain rates are measured in an Instron testing machine. The influences of strain rate on the Young's modulus, 2.5% flow stress and dissipation energy are investigated. It is demonstrated that the area within the stress-strain loop (or dissipation energy) increases with increasing strain rate as well as given strain, that is, all polymers tested exhibit intrinsic dynamic viscoelasticity and a high elastic aftereffect following complete unloading.