This paper presents a review of the different electron microscopy techniques for characterisation of weld microstructures with an emphasis on the techniques to determine morphology, composition and structure determination of ferritic weld metal. The focus will be on techniques which provide an advantage due to either ease of use or greater depth of information, thereby supplementing the information obtained by traditional characterisation techniques such as scanning electron microscopy and transmission electron microscopy. The use of electron backscattered diffraction with orientation imaging microscopy as a tool to understand phase transformation paths and ferrite variant selection will be discussed. The use of energy dispersive X‐ray spectrometry and electron energy loss spectrometry as complementary techniques to determine chemical composition of precipitates will be described. The advantages of annular dark field imaging and bright field scanning transmission electron microscopy for imaging precipitates and defects will be discussed.
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