RT Journal Article SR Electronic A1 Kučerová, Ludmila A1 Jirková, Hana A1 Volkmannová, Julie A1 Vrtáček, Jiří T1 Effect of Aluminium and Manganese Contents on the Microstructure Development of Forged and Annealed TRIP Steel JF Manufacturing Technology Journal YR 2018 VO 18 IS 4 SP 605 OP 610 DO 10.21062/ujep/146.2018/a/1213-2489/MT/18/4/605 UL https://journalmt.com/artkey/mft-201804-0014.php AB Three low carbon steels with 1.5 and 3%Mn and either 1.5%Al or 2%Al were forged from cast ingots into bars using various heating temperatures and deformation conditions. Bars were heat treated by annealing at 950 °C to gain homogenized input materials for subsequent experiments. The effect of various austenitization temperatures and holds in the region of 800 -1200 °C was tested with regard to the final microstructure and hardness development. Hardness in the region of 320-550 HV 10 was obtained. The highest hardness was for all austenitizing temperatures achieved for 1.5Al3Mn steel and it decreased with decreasing manganese to aluminium content ration. This concentration ratio determined transformation behaviour and subsequently also formability of these three steels. Increase of this ratio to 2 for 1.5Al3Mn steel resulted in high tendency to cracking during forging at 1150°C and generally to the shift of phase transformations to lower temperatures and longer times.