TRIP-Assisted Steels?

By H. Bhadeshia. 2002

203 citations recorded by the source corpus.

The weight of an automobile can be reduced by using high-strength steels as long as they have the ductility essential in metal-forming operations. One class of suitable alloys is known as the “TRIP-assisted steels”, in which the microstructure is a mixture of allotriomorphic ferrite and bainite; the term TRIP stands for transformation-induced plasticity. The typical chemical composition is Fe–0.15C– 1.5Si–1.5Mn wt%; the high silicon concentration ensures that cementite is not precipitated during the growth of upper bainite. The carbon that is partitioned from bainitic ferrite stabilises the residual austenite, enabling it to be retained at ambient temperature. The final microstructure typically contains 20% bainitic ferrite, 10% retained austenite with the remainder being allotriomorphic ferrite. There have been many publications on the microstructure and property relationships of TRIP-assisted steels. Most of these studies highlight the presence of the retained austenite and many imply that the observed high uniform elongation is a consequence of the martensitic transformation of the retained austenite under the influence of an applied stress or strain. The purpose of the present work was to investigate theoretically, the magnitude of the contribution that transformation plasticity can make to the total elongation.

Subfields: Aerospace Engineering, Mechanical Engineering, Mechanics of Materials

View Paper: https://www.semanticscholar.org/paper/913594480660fccee2fd26b1578c67381cb1f136