The work deals with the behaviour in tension of a particular structure generated in steels, a mixture of bainitic ferrite and carbon-enriched retained austenite. Tensile stresses were applied to the point of fracture. The raw load-extension data, converted into stresses and strains by considering the specimen geometry, are included in the folder "Tensile-test". Microscopy was carried out using optical, scanning and transmission electron equipment. All the images and diffraction patterns taken are included as .eps, .jpg files. Dilatometric data were produced using the Bahr high-speed dilatometer. Vickers hardness data were determined using a pyramidal diamond indenter. Further experimental details are described in the associated publication, which is included in the dataset.

The details are all given in the README.txt file, but we have included all data generated in the project, of which a limited representative part can actually appear in the publication. For example, we have taken many more micrographs than would appear in the paper