Dynamic shearing resistance of hydroxyl-terminated polybutadiene (HTPB)
Dynamic shearing resistance of hydroxyl-terminated polybutadiene (HTPB)
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DOI：
10.1063/5.0054654
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发表时间：
2021-06
影响因子：
3.2
通讯作者：
P. Malhotra;T. Jiao;D. Henann;R. Clifton;P. Guduru
中科院分区：
文献类型：
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作者：
P. Malhotra;T. Jiao;D. Henann;R. Clifton;P. Guduru
端羟基聚丁二烯（HTPB）是聚合物粘结炸药（PBX）和固体火箭推进剂中广泛使用的聚合物粘结剂。即使以小比例使用，弹性体粘合剂也会吸收大部分冲击能量，因此需要对其机械行为进行仔细建模，以准确模拟PBX在承受大应变和应变率时的响应。虽然HTPB的正常响应的特点是在单轴应力和单轴应变加载下，剪切强度的测量在大压力和大剪切应变率下还没有到目前为止。这种测量对于PBX中的局部化和故障建模以及准确预测热点形成至关重要。本文采用压力剪切平板冲击（PSPI）实验，研究了不同压力下HTPB的抗剪切性能。HTPB的剪切阻力具有很强的压力依赖性。采用剪切波速和剪切阻力与压力相关的准线性粘弹性模型来描述HTPB的动态响应。该模型由瞬时弹性响应和弹性响应的粘弹性松弛组成。
Hydroxyl-terminated polybutadiene (HTPB) is a widely used polymeric binder in polymer-bonded explosives (PBXs) and solid rocket propellants. Even though used in small fractions, the elastomeric binder absorbs much of the impact energy and therefore requires careful modeling of its mechanical behavior to accurately simulate the response of PBXs when they are subjected to large strains and strain rates. While the normal response of HTPB has been characterized under uniaxial stress and uniaxial strain loading, shear strength measurements under large pressures and large shear strain rates have not been made so far. Such measurements are critical for modeling localization and failure in PBXs and accurate prediction hotspot formation. In this study, pressure-shear plate impact (PSPI) experiments have been used to measure the shearing resistance of HTPB at different pressures. The shearing resistance of HTPB is found to be strongly pressure dependent. A quasi-linear viscoelastic model with pressure-dependent shear wave speeds and shearing resistance is used to describe the experimentally observed dynamic response of HTPB. The model consists of an instantaneous elastic response and viscoelastic relaxation of the elastic response.