High strength austenitic-based steel with remarkable toughness of welding heat-affected zone and preparation method therefor

摘要

The present invention relates to a high strength austenitic-based steel with remarkable toughness of a welding heat-affected zone and a preparation method therefor. One embodiment of the present invention provides: a high strength austenitic-based steel with remarkable toughness of a welding heat-affected zone, comprising 0.8-1.5 wt % of C, 15-22 wt % of Mn, 5 wt % or less of Cr (except 0), and the balance of Fe and other inevitable impurities, and further comprising at least one of the following (a) and (b), wherein the microstructure of a welding heat-affected zone comprises 90% or more of austenite by volume fraction; and a preparation method therefor. (a) Mo: 0.1-1% and B: 0.001-0.02% (b) Ti: 0.01-0.3% and N: 0.003-0.1%.