固体发动机绝热层横观各向同性超弹性本构模型  

A transversely isotropic hyperelastic constitutive modelfor insulation layer in solid rocket motors

作　　者：陈胜豪 王春光 李群[1] CHEN Shenghao;WANG Chunguang;LI Qun(State Key Laboratory for Strength and Vibration of Mechanical Structure,School of Aerospace,Xian Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学航天航空学院,复杂服役环境重大装备结构强度与寿命全国重点实验室,西安710049

出　　处：《固体火箭技术》2024年第5期685-693,共9页Journal of Solid Rocket Technology

基　　金：短纤维增强绝热橡胶老化-损伤耦合机理及贮存指标体系研究项目(SY41ZXF2021004)。

摘　　要：固体火箭发动机绝热层因内部存在短纤维,其力学行为难以准确表征,为了建立考虑短纤维影响的本构模型,针对芳纶短纤维增强三元乙丙橡胶材料开展了平行于压延方向(0°)与垂直于压延方向(90°)的拉伸试验,验证了绝热层材料内部短纤维近似定向分布的假设;同时基于断面SEM图像分析了绝热层材料的纤维抽离、纤维断裂、基体损伤等失效行为。基于试验观测,在应变能密度函数中引入纤维项,建立了适用于绝热层材料的横观各向同性超弹性本构模型,并通过0°、45°和90°单轴拉伸试验验证了该模型的准确性,不同角度预测误差均在10%以内。最后,利用该模型给出了在不同方向上绝热层简单变形的应力响应表达式。Due to the presence of short fibers,the mechanical behavior of the insulating layer inside solid rocket motors is difficult to be accurately characterized.In order to establish an accurate constitutive model for the insulation layer,tensile tests on samples parallel to the rolling direction(0°)and perpendicular to the rolling direction(90°)of aramid short fiber reinforced EPDM rubber material were carried out.The assumption of approximate directional distribution of short fibers within the insulation layer material was verified.Additionally,the failure behavior of the insulation material,such as fiber pull-out,fiber fracture,and matrix degradation,were analyzed based on scanning electron microscopy(SEM)image of the fracture surface.Based on experimental observations,a strain energy density function incorporating a fiber term was developed to establish a transversely isotropic hyperelastic constitutive model suitable for the insulation layer material.The accuracy of the model was confirmed through uniaxial tensile tests on 0°,45°and 90°specimens,prediction errors are within 10%for the different angles.Finally,the stress response expressions for simple deformations of the insulation material in different directions were derived using the proposed model.

关 键 词：固体火箭发动机 绝热层 横观各向同性 超弹性模型 短纤维增强橡胶材料 

分 类 号：V255[一般工业技术—材料科学与工程]