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A theory has been developed for the mechanical stabilisation of plastically deformed austenite by balancing the force which drives the transformation interface against the resistance from dislocation debris in the austenite. The work has been used to explain why very large strains are required to mechanically stabilise certain stainless steels, and also to interpret the subunit mechanism of bainite growth.

A variety of different transmission electron microscopy techniques, and particularly high-angle annular dark-field scanning transmission electron microscopy, has been used to reveal that V defects or inverted hexagonal pyramid defects in multiple InGaN / GaN quantum well ͑QW͒ layers nucleate on threading dislocations that cross the InGaN QW. The defects have thin walls lying parallel to ͕101 ¯1͖ with the InGaN / GaN QW structure. A formation mechanism for the V defects is proposed taking into account the growth kinetics of GaN and the segregation of In atoms in the strain field around the cores of the threading dislocations.

Experimental evidence indicates that bainitic ferrite formed by transformation at low temperatures (200-350ºC) contains quantities of carbon in solid solution far beyond those expected from para-equilibrium. A change in the conventional symmetry of the bainitic ferrite lattice from cubic to tetragonal explains the abnormal solid solubility detected. This carbon supersaturation was measured by atom probe tomography, and the tetragonality of the bainitic ferrite, was characterized by means of X-ray diffraction analysis and high resolution transmission electron microscopy.