中等时间尺度下弹道明胶的线性黏弹性模型  

Linear Viscoelastic Model for Ballistic Gelatin at Medium Time Scales

作　　者：马小林[1,2] 范毓润 Xiaolin Ma;Yurun Fan(State Key Laboratory of Fluid Power and Mechatronic Systems,Zhejiang University,Hangzhou 310027,China;School of Mechanical and Electrical Engineering,Hunan City University,Yiyang 413002,China)

机构地区：[1]浙江大学流体动力及机电系统国家重点实验室,浙江杭州310027 [2]湖南城市学院机械与电气工程学院,湖南益阳413002

出　　处：《高分子材料科学与工程》2018年第12期95-100,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金创新研究组资助项目(51221004)

摘　　要：在不同时间尺度下,明胶表现出不同的黏弹性行为。应用蠕变和应力松弛模式研究质量分数为10%的弹道明胶在中等时间尺度下的线性黏弹性行为。低剪切速率下的连续加载-卸载实验显示,在常规感知的时间尺度下(～1min)弹道明胶接近完全弹性体,其线性区应变范围为0～0.25。对蠕变实验对应的中等时间尺度(>1h),选择样品老化24h作为实验起点,这时明胶结构缓慢老化带来的影响可以忽略,从而能够构建恒定参数的本构方程来描述弹道明胶的线性黏弹性行为。对1组蠕变实验结果进行分析,可确定Burgers模型的4个粘弹性参数,然后使用该组参数的模型预测另外2组蠕变实验以及应力松弛实验。结果表明Burgers模型能较好地表征弹道明胶在中等时间尺度下的线性黏弹性行为。Ballistic gelatin is widely used as physical surrogate of biological tissues to simulate blunt impact and blast loading effect on human tissue.Gelatin shows different viscoelastic behaviors at different time scales. The linear viscoelastic behavior of 10% gelatin at medium time scales was studied by rheological creep and relaxation experiments.According to the results of aging experiments of ballistic gelatin,the onset of creep experiment is selected after 24 h of aging,so that the intricate influence of gelatin structural aging during the experiment can be neglected.Therefore,a constitutive equation with constant parameters can be constructed to predict the linear viscoelastic behavior of ballistic gelatin.The linear elastic range of ballistic gelatin was determined by steady shearing and continuous loading-unloading experiments.The experimental data of a group of creep tests were analyzed to determine the four parameters of the Burgers model.Then the model with the same parameter values was used to predict the other two sets of creep experiments and stress relaxation experiments. The experimental results show that the Burgers model can characterize the linear viscoelastic behavior of ballistic gelatin at medium time scales.

关 键 词：弹道明胶 老化行为 中等时间尺度 线性黏弹性 BURGERS模型 蠕变与应力松弛 

分 类 号：O631.13[理学—高分子化学]