Multiscale characterisation of weldments

In this review, a brief introduction to different multiscale characterisation techniques and their application to the characterisation of weldments is presented. The techniques are presented from a historical point of view. The techniques reviewed include optical microscopy, electron microscopy, atom probe field ion microscopy, microhardness mapping and nanoindentation. Although these techniques are discussed with examples from fusion welds, they can easily be applied to solid state welding processes. The paper also refers to other advanced characterisation techniques that are discussed in detail in other sections of this special issue.