EBSD characterisation of grain size distribution and grain sub-structures for ferritic steel weld metals

Abstract Microstructural characterisation of engineering materials is required for understanding the relationships between microstructure and mechanical properties. Conventionally grain size measured from boundary maps obtained using optical or electron microscopy. This paper implements EBSD-based linear intercept measurement spatial variation ferritic steel weld metals, making analysis flexible robust. While has been shown to correlate with strength material according Hall–Petch relationship, similar sizes in metals different phase volume fractions can have significantly Furthermore, solidification pool induces formation sub-structures that alter The recently developed domain misorientation approach used this study provide a more comprehensive metals. studied consist varying mixtures primary ferrite, acicular bainite/martensite, large differences observed hardness, size, morphology, dislocation cell size. For average varied 0.68 1.41 µm, bainitic/martensitic showing smallest ferrite largest. In contrast, volume-weighted was largest metal. Results indicate Hall–Petch-type relationship exists hardness it partially corrects size—hardness methods datasets are provided as open access.