在循环压缩下对聚合物结合爆炸模拟剂局部变形和损伤行为的实验研究
Dong Jia1,2, Zhiming Hao1,2, Yunqiang Peng1
1Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621999, China.
Materials (Basel, Switzerland)
|February 24, 2024
概括
这项研究研究了在循环压缩下聚合物结合爆炸物 (PBX) 模拟剂损伤. 关键发现揭示了不同的变形阶段和故障机制,其中应变不变I1量化了损伤进展.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 聚合物结合爆炸物 (PBX) 是关键的能量材料,需要详细了解它们的机械行为.
- 调查PBX模拟器在循环负荷下变形和损坏对于预测性能和确保安全至关重要.
研究的目的:
- 在单轴循环压缩下分析聚合物结合爆炸物 (PBX) 模拟剂的压缩变形和损伤,特别是剪切定位.
- 阐明中大尺度故障机制和宏观机械反应.
主要方法:
- 在PBX模拟器上进行了单轴循环压缩测试.
- 光学显微镜和扫描电子显微镜 (SEM) 用于表面分析.
- 使用X射线计算机断层扫描 (CT) 和数字体积相关性 (DVC) 来分析内部3D变形.
主要成果:
- 应力-应变曲线呈现出五个不同的阶段,与表面形态变化相关.
- 中等尺度故障涉及颗粒结合剂解和结合剂撕裂,微小的颗粒断裂.
- 确定了三个菌株分支点 (T1,T2,T3),标志着损伤演变中的转变,从均到局部失效.
结论:
- 识别的分叉点准确地反映了损伤的进展,包括剪切位置和骨折.
- 应变不变I1提供了PBX模拟器在循环压缩下变形和损坏的全面定量测量.
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