Uma discussão sobre aços de Plasticidade Induzida por Maclação Mecânica (TWIP) aplicados na indústria automobilística.

Abstract

With the automobilist industry evolution attributes such as safety, sustainability and performance has directed the area to a search for new materials with unique properties. Among the ferrous and non-ferrous alloys stands out the TWIP steel for its combination of high plasticity and mechanical strength. TWIP steels are characterized as high manganese content and contain in their composition other alloying elements such as carbon, copper, aluminum and silicon. The alloying elements content is controlled in a way that makes the TWIP steel reach specifics values of stacking fault energy, Hollomon coefficient, and stabilize the austenitic phase. All these parameters are controlled to make mechanical twinning present in this steel, guaranteeing an exceptional properties combination. TWIP steels show a great hardening capacity and extended plasticity, and can reach 1930 MPa UTS, and 95% elongations. This alloy presents some implications that harden its processability but can be fixed with alloying elements or extra care on process. Furthermore, TWIP has temperature and strain rate sensitivity, however presents adequate properties to security against crash applications. TWIP fabrication demands high control level and has high costs due to the manganese ore processing. Although TWIP’s great technological potential, there is low availability in domestic and international market due its high cost. It’s recommended to future works to study alternative technological applications that justifies its commercial value, or ways to reduce fabrication costs.