5th International High Manganese Steel Conference - HMNS 2022

The objective of the present study is to develop the steels with the reasonable materials cost to replace the Fe-9Ni (wt.%) steel known as the materials for the cryogenic application. We designed the Fe-xMn-yNi-0.1C steel, and the quenching-tempering (QT) process and quenching-lamellarizing-tempering (QLT) process were applied to corresponding steel to optimize the microstructure and mechanical properties. The QLT-processed steel revealed a higher impact absorbed energy at –196 °C (~193 J) than the QT-processed steel (~168 J), showing a similar value with Fe-9Ni steel. The soft martensitic matrix from two-step annealing and pronounced transformation-induced plasticity from retained austenite led to the high damage tolerance and improved toughness of QLT sample.