|
| 基于同步辐射原位显微CT的铝基复合泡沫变形破坏过程研究 |
| Deformation dynamics of an aluminum martix composite foam: An in situ synchrotron tomography study |
| 投稿时间：2024-02-05 修订日期：2024-04-28 |
| DOI： |
| 中文关键词: 铝基复合泡沫材料 原位显微CT 三维数字图像分析 微观结构演化 |
| 英文关键词:Aluminum syntactic foam In situ micro computed tomography 3D digital image analysis Structural evolution |
| 基金项目: |
|
| 摘要点击次数: 607 |
| 全文下载次数: 0 |
| 中文摘要: |
| 本文基于上海同步辐射光源BL16U2线站及自主研发的材料试验机搭建了一套原位显微CT系统，研究了掺空心微珠的新型铝基复合泡沫材料在准静态单轴压缩下的三维结构变形破坏过程。原位显微CT系统获得了目标试样在准静态压缩下的宏观工程应力-工程应变曲线及数个应变处的三维结构模型。基于三维数字图像分析手段，量化表征了目标试样内孔洞形貌参数的演化历程，追踪了数个典型胞元的坍塌过程。预坍塌阶段，试样内存在少量空心微珠破碎，试样不完全是弹性变形。进入平台阶段后，基体中的空心微球被大量压缩破坏并形成斜向剪切带，应变持续增加而应力保持稳定，直至大部分胞元破碎崩溃，碎块在胞元坍塌后的缝隙间填充，试样整体逐渐致密化。跟踪单个胞元的坍塌，球形度越高的孔抗压能力越强，最长轴朝向垂直于加载方向的孔最容易被破坏。周围分布有密集小型孔洞的胞元率先破裂，并诱导临近胞元塌陷。 |
| 英文摘要: |
| Based on X-ray fast imaging beamline (BL16U2) at Shanghai synchrotron radiation facility and a home-made material test system, in situ micro-CT system is set up to study the three-dimensional structural deformation and failure process of an aluminum syntactic foam doped with hollow microbeads under quasi-static uniaxial compression. The bulk engineering stress-strain curve of the specimen under quasi-static compression and the three-dimensional structural models under the specified strain states are obtained by in situ micro-CT system. Based on 3D digital image analysis methods, the evolution of pore morphology parameters and the collapse process of cells are quantified. In the pre-collapse stage, a small number of hollow microbeads are broken, and it’s not exactly elastic deformation. After entering the plateau stage, a large number of hollow microbeads in the matrix are destroyed and an oblique shear zone is formed. The strain continue to increase while the stress remained stable until most of the cells broke and collapsed, and fragments filled in the gaps after cell collapse, and the whole specimen gradually densified. Tracking the collapse of several cells, the cells with higher sphericity has stronger compressive resistance, and the cells with the longest axis perpendicular to the loading direction is the most easily destroyed. The cell with dense small pores around it breaks first and induces adjacent cell collapse. |
| 下载PDF阅读器 |
| 关闭 |
