关于HTPB推进剂在疲劳负荷下机械性质及其机制演变的实验研究
Feiyang Feng1, Xiong Chen1, Jinsheng Xu1
1Key Laboratory of Special Engine Technology, School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Polymers
|October 28, 2025
概括
疲劳负荷降解基终结聚乙烯 (HTPB) 推进剂,减少随时间的剩余延长. 使用威廉姆斯-兰德尔-费里理论的新模型预测了这种退化,有助于长期性能评估.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 机械工程 机械工程
背景情况:
- 基终结聚乙烯 (HTPB) 推进剂是重要的能量材料.
- 了解它们在疲劳时的机械性质演变对于安全性和可靠性至关重要.
- 疲劳负荷可能导致过早故障和性能恶化.
研究的目的:
- 为了研究受疲劳负荷的HTPB推进剂的机械性能变化.
- 描述残留延长的演变,作为材料降解的关键指标.
- 识别导致财产变化的潜在中层结构损害机制.
主要方法:
- 对HTPB标本进行了疲劳测试,在不同的最大应力和周期数下进行.
- 在疲劳后的样本上进行了单轴拉伸试验,以评估剩余的机械性能.
- 扫描电子显微镜 (SEM) 用于分析中介结构形态变化.
- 威廉姆斯-兰德尔-费里 (WLF) 理论被应用于开发残余延长衰变的主曲线.
主要成果:
- 随着疲劳周期的增加,残留延长减少,呈现出三种不同的衰退阶段 (缓慢变化,逐渐衰退,快速恶化),取决于压力水平.
- SEM 揭示了损伤机制,如"露水"和粒子碎裂在中层结构层面.
- 一个基于WLF理论的概括模型准确地预测了疲劳负荷下的材料降解.
结论:
- 疲劳负荷显著影响HTPB推进剂的机械完整性.
- 半结构损伤机制与观察到的残余延伸减少直接相关.
- 开发的基于WLF的模型为预测HTPB推进剂降解和评估长期性能提供了经过验证的方法.
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