Phase-Specific Analysis and Simulation of Micro Deformation and Damage in Metal Matrix Composites

金属基复合材料微变形和损伤的相特异性分析与模拟

• 批准号: 298892085
• 负责人: Professor Dr. Siegfried Schmauder
• 金额: --
• 依托单位: Lehrstuhl für Werkstofftechnologie (LWT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/298892085?language=en
• 关键词: Phase; Specific; Analysis; Simulation; Micro

The localization of strain and the nucleation of micro damages in ductile materials like metals are of high technical significance since these microstructural processes affect the mechanical behavior during loading, forming and machining of such materials. Moreover, there is a relationship between the regions of elevated strain on one side and the sites of micro damages and the modes of macroscopic failure on the other side. In order to control such microstructural processes, metallic materials are reinforced for example by dispersing hard particles. Such metal matrix composites (MMCs) have become more and more attractive since their mechanical properties can be tailored to various applications over a wide range.Using a combination of 2D/3D experimental analysis and simulation techniques and under consideration of residual stresses, this project aims at the understanding of micro deformation and damage processes in microstructural regions of MMCs by the example of the system Co/WC diamond:Specimens made of various Co/WC diamond MMCs will be loaded in tension to different stages of strain. In these stages, the gauge sections of the specimens are imaged by SEM and 3D micro-tomography (µCT). With a test rig which will be constructed in the project and which is dedicated for the µCT setup in situ tensile tests will be carried out. A correlation algorithm for the phase-specific analyses of the 3D strain fields will be developed and applied to the 3D images. This iterative correlation algorithm takes into account the distributions of the phases in the microstructure which can be extracted from the tomographic images. Furthermore, the effect of residual stresses, microstructural parameters and the Co/diamond bonding on the initiation of strain and stress concentration sites and the beginning of damage at a microscopic scale will be investigated.Based on the experimentally obtained phase distributions a realistic 3D FE model of the phase geometry of the Co/WC diamond MMC will be built up to simulate the micro deformation and damage processes of the investigated MMC. Displacement vector fields measured at the model boundaries will be used as boundary conditions for the FE simulation. The comparison of the simulation results with the experimental findings on the basis of strain fields, residual stresses and damage processes will help to verify the simulation model. With such a verified numerical model, it will be possible to derive a better understanding of the deformation and damage behavior of the composite by performing parameter studies concerning different phase arrangements and different phase volume fractions. The close cooperation between the experimental analyses and simulations is considered to be a key element for achieving these aims.

由于这些微观结构过程会影响加载，形成和加工在此类材料的加载，形成和加工过程中的机械行为，因此应变的定位和延性材料中微型损伤的成核具有很高的技术意义。此外，一侧升高的应变区域与微观损害的位置与另一侧的宏观衰竭模式之间存在关系。为了控制此类微观结构过程，例如通过分散硬颗粒来加强金属材料。这种金属矩阵组合物（MMC）变得越来越有吸引力，因为它们的机械性能可以在较大范围内针对各种应用量身定制。使用2D/3D实验分析和仿真技术的组合以及在考虑残留压力的情况下，该项目的目标是理解MMC/MMC的微型降落区域的理解：MMC的examples cocy/cos cos cos cocy cos cocy cocy cocy cocy cocy cos yc cos of MMC的系统： CO/WC Diamond MMC将以张力加载到不同的应变阶段。在这些阶段，样品的仪表部分由SEM和3D微型摄影（µCT）成像。将在项目中构建的测试钻机，并将用于用于原位拉伸测试的µCT设置。将开发并应用于3D图像的3D应变场的相位特异性分析的相关算法。这种迭代相关算法考虑了可以从层析成像图像中提取的微观结构中相的分布。 Furthermore, the effect of residual stresses, microstructural parameters and the Co/diamond bonding on the initiative of strain and stress concentration sites and the beginning of damage at a microscopic scale will be investigated.Based on the experimentally obtained phase distributions a realistic 3D FE model of the phase geometry of the Co/WC diamond MMC will be built up to simulate the micro deformation and damage processes of the investigated MMC。在模型边界上测量的位移矢量场将用作FE模拟的边界条件。基于应变场，残留应力和损伤过程的模拟结果与实验发现的比较将有助于验证模拟模型。通过这样验证的数值模型，可以通过对不同相位布置和不同相体积分数进行参数研究来更好地理解复合物的变形和损伤行为。实验分析和模拟之间的密切合作被认为是实现这些目标的关键要素。