Análise da transformação martensítica induzida por deformação em aços com efeito TRIP

Abstract

In pursuit of advanced automotive solutions, high strength steels (AHSS, High Strength Steels) have been improved to replace advanced high strength steels as they can enhance and improve the safety of mechanical vehicles. Among the AHSS, TRIP (Transformation Induced Plasticity) steels stand out, which propose a microstructure consisting of ferritic and bainitic grains with austenite islands. One of the main characteristics of TRIP steels is the occurrence of martensitic transformation induced by plastic deformation, promoting high coefficient of work hardening, high plasticity and toughness. In this work, two samples of different classes of cold rolled TRIP steels were used, with 690 and 780 MPa of resistance limit with approximately 1.5 mm of thickness. As they were manually bent at 90° with the aid of a vise and later embedded and metallographically prepared to be made via EBSD (Electron Backscattering Diffraction). They were carried out along the cross section of the sample in the deformed and long region of the bend, as a comparative basis of the microstructural evolution of the material as a function of deformation. It was possible to study the behavior of the microstructure in different functions, becoming an applied training model. From the EBSD formation formation variations, it was possible to evaluate the diversity of plastic formation variations, in addition to the evaluation of the plastic formation distribution, in addition to the evaluation of the microstructure formation distribution. Where it was possible to analyze it after the transformation of the austenite of metastable plasticity in increasing the mechanical properties of this material, characteristic of this great importance in the control of this class of steels.