动态压缩行为,构成型建模和30体积%B的完整失败标准C/2024Al复合材料
Qiang Yan1, Zhihong Zhao1, Tian Luo2
1Institute of Defense Engineering, Academy of Military Science, People's Liberation Army, Beijing 100036, China.
Materials (Basel, Switzerland)
|March 13, 2025
概括
这项研究增强了碳化物/复合材料的约翰逊-库克模型,准确预测动态负载下塑料变形和故障. 修改后的模型捕捉了应变软化和裂传播,这对于材料设计至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 碳化物 (B4C) / (Al) 复合材料是具有重要的工程应用的先进材料.
- 了解它们在动态负载和变化温度下的行为对于性能预测至关重要.
- 现有的模型可能无法完全捕捉这些复合材料中复杂的变形和故障机制.
研究的目的:
- 研究B4C/Al复合材料在准静态和动态负荷下的压缩行为.
- 开发和验证一个修改的约翰逊-库克 (JC) 模型,对这些复合材料具有完全失败标准.
- 分析收益强度增强和材料故障的潜在机制.
主要方法:
- 在各种负载条件和温度下对B4C/Al复合材料的实验研究.
- 修改 JC 模型并开发一个故障标准.
- 使用Abaqus的有限元分析 (FEA) 与一个用户子程序 (VUHARD) 结合了修改的JC (MJC) 模型和故障标准.
- 微结构分析以确定故障机制.
主要成果:
- 在复合材料的应力-应力曲线中观察到应力软化.
- 泰勒和负载转移机制显著促进了产力强度的提高 (89.6%).
- 粒子断裂和矩阵损伤是主要的故障机制,微裂通过矩阵,接口或粒子传播.
- 在动态负载下预测塑料变形时,MJC模型实现了高准确度 (MAE <15%).
- FEA模拟准确地捕获了塑料变形和裂传播.
结论:
- 经过修改的约翰逊-库克模型和故障标准提供了一个准确的B4C/Al复合材料在动态负载下的表现.
- 该研究阐明了控制这些复合材料产量强度和故障的关键机制.
- 这项工作提供了一个有价值的计算工具,用于预测陶增强矩阵复合材料的性能.
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