Análise da influência dos ciclos térmicos de diferentes projetos de fornos recozimento contínuo na microestrutura e propriedades mecânicas de aços bifásicos galvanizados

Abstract

The automotive industry has increasing their competitive and the steel companies are investing in the development of high strength steels such as dual phase steels, which have a good combination of strength, formability and weldability. This work has for objective to present the results of an experience in an industrial plant carried out in lines of the hot dip galvanizing; where it was verified the influence of the thermal profile of different designs of continuous annealing furnaces on the microstructure and mechanical properties of two galvanized dual phase steels. Mechanical tests and microstructure characterization were performed. The results show that high heating rates before the annealing at intercritical temperatures, and low equalization time provide a microstructure with a greater volume fraction of martensite and, consequently, higher values of tensile strength.