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The homogenization treatment is shown to have profound effects on the decomposition of austenite, suppression of microstructural banding, and work-hardening capacity of transformation-induced plasticity (TRIP) steels. Due to the similarity in the activity of carbon in different parts of the parent austenite phase and its extremely coarse grain size, a nearly full homogenization annealing results in the massive-like transformation during subsequent decomposition of austenite at slow cooling rates.

AISI 304L stainless steel wires are cold drawn to different strains for examining the effect of plastic deformation on the mechanical properties change, the microstructural evolution, and martensitic transformation. Microstructures of drawn wires are characterized using optical microscopy, X-ray diffraction and electron backscatter diffraction (EBSD) techniques. It is shown that deformed structure consists of austenite, ά-martensite, and ϵ-martensite. The ultimate strength of wires drawn to strains of 0.56, 1.13, and 1.7 are found to be equal to to 1028, 1492, and 1743 MPa, respectively, from intial value of 735 MPa. These strengths are correspond to the strain induced martensite of 34, 62, and 100%. Also, it is shown that elastic modulus of wires are changed due to the strain induced transformation during cold drawing. For accessing the strain distribution during wire drawing, FEM simulations are carried out according to the experimental investigations. By help of simulation results and applying different criteria, it is shown that regions near the wire surface are suitable area for initiation of strain induced martensite. Moreover, microstructural observations and hardness measurements reveal that the amount of strain-induced martensite is higher just below the surface.

The importance of deformed microstructure before transformation-induced plasticity (TRIP) heat treatment in transformation-induced plasticity steels was taken into account. The heavily cold-rolled sheet was annealed at 650 °C for enough time to replace the deformed microstructure with a recrystallized one. It was revealed that the tensile strength, ductility, strain-hardening capability, and TRIP effect are significantly impaired by the annealing of cold-rolled sheets. This was explained based on the distribution of the retained austenite phase, strength of ferritic matrix, and the deformation-induced martensitic transformation.