宽γ辐照剂量范围内硅泡沫本构模型研究  

Constitutive Model for Silicone Rubber Foam over a Wide Range ofγRadiation

作　　者：晏顺坪 余勇[1] 王罗斌 邱勇[1] 万强[1] Shunping Yan;Yong Yu;Luobin Wang;Yong Qiu;Qiang Wan(Institute of Systems Engineering,China Academy of Engineering Physics,Mianyang,621999)

机构地区：[1]中国工程物理研究院总体工程研究所

出　　处：《固体力学学报》2020年第6期555-566,共12页Chinese Journal of Solid Mechanics

基　　金：NSAF重点基金项目(U1530259);国家自然科学基金项目(11632001,11602254);挑战计划项目(TZ2018007)资助.

摘　　要：基于实验和理论建模研究了白炭黑增强硅泡沫材料在γ辐照剂量范围为0~1000kGy作用后的单轴压缩力学行为.实验结果表明辐照导致硅泡沫出现明显硬化现象,初始杨氏模量和固定应变下应力幅值均随γ辐照剂量近似线性增加.辐照后硅泡沫泡孔结构完整,硅橡胶基体中高分子交联反应占主导,且交联密度随辐照剂量线性增大.基于实验分析结果,实现了Ogden Hyperfoam超弹本构模型参数与辐照剂量的关联.结果表明初始剪切模量参数与辐照剂量成线性关系,硬化指数和泊松比参数与辐照剂量无关.基于应力应变实验数据拟合得到模型参数,并与未参与拟合的实验数据对比,验证了模型的准确性,表明该模型能够表征宽辐照剂量范围内硅泡沫的压缩力学行为.Silicone rubber foam materials are widely used in industrial and biomedical fields.When exposed toγradiation,silicone rubber foam undergoes chemical changes and shows degraded mechanical performances.Hence,it is essential to establish a radiation-dose-related mechanical model to describe the mechanical behavior of silicone rubber foam underγradiation.In this work,the uniaxial compression behavior of silica-reinforced silicone rubber foam exposed toγradiation with a wide range of 0~1000kGy is investigated by mechanical tests and theoretical modeling.The experimental results show thatγradiation results in a significant hardening effect on the silicone rubber foam.The initial Young’s modulus and the stress for a particular strain both increase linearly with theγ-radiation dose.The radiation-induced hardening behavior is ascribed to the predominant chemical crosslinking reactions of silicone rubber matrix,confirmed by the solvent swelling measurement.The crosslink density of silicone rubber matrix increases linearly with the radiation dose.The scanning electron microscope shows that the void structure of silicone rubber foam does not change when irradiated.Based on experimental observations,the Ogden Hyperfoam model is generalized to describe the hyperelastic response of silicone rubber foam over a wide range ofγradiation,by correlating the model parameters with radiation dose.The initial shear-modulus-related parameters are redefined as a linear function of radiation dose,and the strain hardening exponent and Poisson’sratio-related parameters are independent of radiation dose.In the end,model parameters for the second order of the generalized Hyperfoam model are estimated based on the uniaxial compression test data,and the prediction ability of the radiation-related model is verified.The results indicate that the proposed model is capable of characterizing the large deformation behavior of silicone rubber foam for the investigated dose range.The model can be helpful in preparing silicon rubber foam materia

关 键 词：硅橡胶泡沫 Γ辐照 单轴压缩 本构模型 

分 类 号：TQ328[化学工程—合成树脂塑料工业]