Challenges in microstructural metrology for advanced engineered materials

Abstract

Measurement of microstructural parameters is essential for both controlling and modelling properties of and production processes for advanced materials. In the past decade new techniques such as electron backscatter diffraction have enabled a considerable increase in the amount of data and degree of detail in microstructural measurements of, for example, the extent of recrystallization in a metal deformed at high temperatures. However, the many parameters involved and automated nature of the methods can lead to artefacts and bias in calculated values, and increased resolution will lead to disagreement with more conventional methods. Examples are given of the range of microstructural measurements possible by new techniques and how different results can be obtained from the same underlying data. The need is stressed for interlaboratory comparisons to enable underpinning data to be derived on the validity, repeatability and reproducibility of measurements of key microstructural parameters.