Residual stress analysis by neutron and X-ray diffraction applied to the study of two phase materials: Metal matrix composites
Residual stress analysis by neutron and X-ray diffraction applied to the study of two phase materials: Metal matrix composites
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DOI：
10.1111/j.1747-1567.1996.tb00893.x
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发表时间：
1996-05
影响因子：
1.6
通讯作者：
M. Ceretti;C. Braham;J. Lebrun;J. Bonnafe;M. Perrin;A. Lodini
中科院分区：
文献类型：
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作者：
M. Ceretti;C. Braham;J. Lebrun;J. Bonnafe;M. Perrin;A. Lodini
近年来，金属基复合材料（MMCs）在其结构部件的应用中变得重要，因为与常规合金相比，该材料在高温下具有改善的比强度和蠕变性能。当MMC在高温下制造或退火并冷却至室温时，残余应力被引入基体和增强体中，这基本上是因为两种成分的热膨胀系数之间的显著差异。这些残余应力可能会对材料的机械性能和疲劳损伤产生不良影响，因此对其进行评估至关重要。在金属基复合材料的塑性变形过程中也会引入残余应力。硬增强颗粒的存在促进了材料中的非均匀流动，从而在去除施加的载荷时产生残余应力。用X射线和中子衍射方法测量了复合材料中的平均残余弹性应变。实际上，衍射技术是研究MMC中残余应力的有力工具，因为可以分析基体和增强体，因为它们给出单独的衍射图案。
In recent years metal matrix composites (MMCs) became important in their application to structural components as materials with improved specific strength and creep properties at elevated temperatures compared to conventional alloys. When MMCs are fabricated or annealed at a high temperature and cooled down to room temperature, residual stresses are induced into the matrix and the reinforcement, essentially because of the significant difference between the thermal expansion coefficients of the two constituents. These residual stresses may have undesirable effects on the mechanical properties and the fatigue damage of the materials and thus their evaluation is of fundamental importance. Residual stresses are also introduced during plastic deformation of metal matrix composites. The presence of hard reinforcement particles promotes nonhomogeneous flow in the material, resulting in residual stress when the applied load is removed.Average residual elastic strains in composites have been measured both by X-ray and neutron diffraction methods.'-6 Diffraction techniques are, in fact, powerful tools to investigate residual stresses in MMCs, since it is possible to analyze both the matrix and the reinforcement as they give separate diffraction patterns.