发表机构
Institut Langevin, ESPCI Paris, PSL University, CNRS; Safran Tech（朗之万研究所，巴黎高等物理化工学院，巴黎文理研究大学，法国国家科学研究中心; 赛峰科技）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出一种基于超声反射矩阵的方法，通过分析背散射波估计多晶材料的纵波与横波速度，进而推导弹性常数，并经实验与模拟验证，展现定量无损表征潜力。
AI 中文摘要
对非均质材料的深入表征长期以来一直是无损检测领域的一项挑战。本文提出了一种利用背散射超声确定金属多晶材料弹性常数的方法。通过分析由微结构散射的波来成像有效体波速度。为此，使用换能器阵列采集反射矩阵。将该矩阵投影到聚焦基上，用于估计平均点扩散函数。针对传播模型优化该函数，可实现对纵波速度的估计。进一步开发了附加处理，使该方法适用于横波速度的映射。随后，由这两种速度之比推导出局部泊松比。在假设密度已知的情况下，还可获得杨氏模量和剪切模量。该矩阵方法在不同多晶材料上得到了实验验证。随后，对一块具有非均质力学性能的样品进行模拟，以评估该方法的精度和分辨率。讨论了其优势与局限性，展示了其在定量无损材料表征方面的潜力。
英文摘要
In-depth characterization of heterogeneous materials has long been a challenge in non-destructive testing. Here, a method is proposed to determine the elastic constants of metallic polycrystalline materials using back-scattered ultrasound. The waves scattered by the microstructure are analyzed to image the effective bulk velocities. To this end, a reflection matrix is acquired with an array of transducers. The projection of this matrix onto a focused basis is used to estimate an average point spread function. Optimizing this function with respect to the propagation model leads to an estimation of the longitudinal velocity. Additional treatments are developed to adapt the method to map the shear wave velocity. The local Poisson's ratio is then deduced from the ratio between those two velocities. Young's modulus and shear modulus can also be obtained assuming known densities. This matrix approach is experimentally validated on different polycrystalline materials. A sample displaying heterogeneous mechanical properties is then simulated to assess the accuracy and the resolution of the method. Its strengths and limitations are discussed, demonstrating its potential for quantitative non-destructive material characterization.
Comments13 pages, 14 figures
