Quantitative characterisation of metals using multiple scattering of ultrasonic waves

该项目将侧重于利用超声多次散射现象来定量表征金属材料的微观结构特性（晶粒尺寸和形状或尺寸以及微观织构区域的各向异性晶体取向）。与使用单个传感器的传统测量相比，有几个主要优点。首先，该方法完全基于发射器接收器后向散射阵列数据的后处理，并且不需要阵列硬件的任何改变或对样品的几何形状的特定要求。其次，可以提取材料的每个局部区域的数据，这导致每个局部材料区域的微观结构表征的可能性。第三，该方法还可以用于检测和定位弱的局部材料不均匀性，这是不可检测的使用常规成像（例如，显微纹理区域，蠕变损伤）。该项目包括几项任务，概述如下。- 粗颗粒材料阵列数据快速半分析模型的开发，其中包括超声波的多次散射。- 发展有效的算法，从阵列数据中提取多个散射参数。- 不同多次散射参数对材料微结构的敏感性研究。- 发展有效的方案来解决从提取的多次散射特性估计微结构特性的逆问题。- 实验验证。- 软件演示器的开发。

This project will focus on exploiting ultrasound multiple scattering phenomenon to quantitatively characterise microstructural properties of metallic materials (grain size and shape or size and the anisotropic crystal orientation of micro-textured regions). There are several major advantages compared to the traditional measurements using a single transducer. Firstly, the approach is based entirely on post-processing of the transmitter receiver backscattering array data and does not require any changes in array hardware or specific requirements on the specimen's geometry. Secondly, it is possible to extract data for each local area of the material, which leads to the possibility of microstructural characterisation of each local material region. Thirdly, the method can also be used for detection and localisation of weak local material inhomogeneities, which are undetectable using conventional imaging (for example, microtextured regions, creep damage). The project consists of several tasks, briefly outlined below. - Development of the fast semi-analytical model of array data for coarse grain materials, which includes multiple scattering of ultrasonic waves. - Development of efficient algorithms to extract multiple scattering parameters from the array data. - Sensitivity study of different multiple scattering parameters to material microstructure. - Development of efficient scheme to solve the inverse problem of estimating microstructural properties from extracted multiple scattering characteristics. - Experimental validation. - Development of software demonstrator.