Processing and characterization of lightweight steels by semi-industrial spray forming equipment

Abstract

The lightweight steels are advanced alloys belonging to Fe-Mn-Al-C system which are being developed focusing on automotive applications. This class of alloys present high level of mechanical properties allied to a lower density in comparison to conventional steels. The mechanical properties of austenite-based alloys are one of the main topic being studied, since some compositions may present some effects as: Transformation Induced Plasticity (TRIP), Twinning Induced Plasticity (TWIP) or Micro-band Induced Plasticity (MBIP). The main variable which governs the plastic behavior is the stacking fault energy (SFE), but also the grain size and the alloying elements may be crucial for the occurrence of such phenomena. The objective of this research internship is to process three different compositions of a lightweight steel on a semi-industrial spray forming equipment and consequently evaluate the effects of the processing on the mechanical properties. This research internship abroad project aims to the doctoral student spend a period at the Leibniz Institute for Materials Engineering of Bremen University (IWT - Leibniz-Institut für Werkstofforientierte Technologien) under the supervision of Dr. Volker Uhlenwinkel working on the spray forming of the three most prominent compositions evaluated previously on a laboratory scale. It can be mentioned that the spray forming is an advanced technique which produces materials with a high level of homogeneity and with a microstructure of equiaxed grains directly from the liquid. A larger scale experiment will show a novel possibility to produce these materials and allow checking the possibility of maintaining the excellent properties observed at laboratory scale.