(Dr. David McDowell, advisor)
"TRIP Steel Behavior"
To address low thickness sheet manufacture, several studies are underway. In addition to microstructure control during successive forming operations, another possible way is the development of new steels with high ductility and strength. This research project deals with the second alternative, using the TRIP effect in steels (TRansformation Induced Plasticity). This new kind of steel has very interesting properties such as a coupling between high fracture ductility (30-50%) and strength (800-1300 MPa).
Inelastic anisotropy is used in forming processes to improve drawing
of materials; it results from crystallographic texture. Deformation-induced
texture comes from the lattice rotation associated with plastic slip and
kinematic boundary conditions related to intergranular constraints. These
attractive mechanical properties are due to an additional plastic strain
(transformation plasticity) due to the transformation from austenite to
martensite, beyond the classical plastic strain of steels. For a better
understanding of these mechanisms, experiments on the evolution of texture
during the transformation and on transformation plasticity will be presented.