The current growth in the automotive, aerospace, and energy generation industries has created a requirement for new metallic alloys with both high strength and ductility, and that retains these properties over a wide range of temperatures. Mechanical properties of metals are dependent on grain structure (grain size, shape, and the interface properties between neighboring grains), phase balance (type and fraction of constituent phases), the morphology and chemical composition of hard particles, and the arrangement of dislocations. Therefore, microstructural characterization is an important approach for discovering the relationships between the chemical composition, processing parameters, and mechanical properties of new materials.

In general, increasing the strength of a material is achieved at the expense of ductility, which is a difficult challenge to overcome. In situ experiments and ex situ observations using scanning electron microscopy (SEM) can significantly help to understand this strength-ductility paradox and provide possible solutions to allow for the adaptation of processing routes to minimize the losses in ductility while maximizing gains in material strength.

The aim of this special issue is to disseminate the latest findings and efforts of specialists concerned with scanning-based microstructure characterization techniques such as secondary and backscattering electron imaging, energy dispersive X-ray spectroscopy (EDS), electron backscattering diffraction (EBSD), transmission Kikuchi diffraction (TKD), and in situ heating and deformation in SEM applied in metallurgical research. Original research articles, as well as review papers, are welcome.

Potential topics include but are not limited to the following:

• Microstructure characterization of steels, aluminum, nickel, titanium, magnesium, hybrid metallic structures, and multiple principal element alloys
• The effect of processing routes (thermomechanical processing, heat treatment, severe plastic deformation, friction stirring processes, joining, additive manufacturing, etc.) on microstructure evolution
• Fracture surface characterization for the determination of fracture mode
• In situ or ex situ SEM for microstructure characterization during deformation
• Precipitation characterization by SEM correlated with EDS for chemical analysis
• Analysis of crack propagation by SEM and, in turn, of the relationship between microstructure and fracture resistance