Acta Metallurgica Slovaca, Vol. 16, 2010, No.4, p. 261-267 261 DEFORMATION MODE IN AZ31 MAGNESIUM ALLOY DURING COMPRESSION TESTS E. Hadasik, D. Kuc Silesian University of Technology, Faculty of Materials Engineering and Metallurgy Krasińskiego 8, 40-019 Katowice, Poland Received 24.05.2010 Accepted 08.12.2010 Corresponding author: Eugeniusz Hadasik, Telephone number +4832 603 4474, Department of Process Modelling and Medical Engineering, Faculty of Materials Engineering and Metallurgy, Krasińskiego 8, 40-019 Katowice, Poland. E-mail: eugeniusz.hadasik@polsl.pl Abstract Usage of magnesium alloys constantly increase, especially in the area of automotive industry. Classification of magnesium alloys for forming, production process by rolling, extrusion and forging have been presented. Moreover, the difficulties in magnesium manufacturing have been presented as well. The relations between microstructure and deformation parameters in AZ31 magnesium alloy have been studied. Two main deformation processes: twinning and slipping have been shown. The changes in the plastic characteristics as a function of the Zener-Hollomon parameter have been presented. The research carried out enabled the understanding of the phenomena taking place during deformation and annealing of the investigated AZ31 type alloy. The results will constitute the basis for modelling the structural changes. Keywords: magnesium alloy, high temperature deformation, dynamic recrystallization, slip, twinning 1 Introduction The current trends in the automotive, aircraft and space industries focus first and foremost on a reduction of the vehicle weight and saving energy, thereby protecting the environment. Such a set of technical, economical and ecological aspects arouses a considerable interest of the industry in light alloys. Owing to a number of their advantageous mechanical properties including, first of all, low density (1.74 g/cm 3 ), magnesium alloys are more and more frequently used as an engineering material. There is a regular increase visible in the number of components made of magnesium alloys in the car structure [1-4]. However, for the production of components from magnesium alloys, casting processes are still most often applied. Alloys used for plastic working are less popular compared to those processed via casting and therefore, the number of their grades is much smaller. The number of alloying components in cast magnesium alloys is always higher than in alloys subject to plastic working. Alloys from the group Mg-Al-Zn-Mn have the best set of properties, for they contain as much as 8 % Al with an addition of Mn (up to 2 %) and Zn (up to 1.5 %). From among elements subjected to plastic working, sheet metal deserves special attention, for it can be applied for the construction of light vehicles [3-8]. In connection with the complexity of the phenomena which take place in the microstructure, a number of studies in the field of Mg-Al-Zn alloys subjected to plastic working are focused on