| 摘要 |
<p>The present invention relates to a low-temperature molten steel with excellent toughness in a welding heat affected part and a manufacturing method thereof. The present invention provides low-temperature molten steel with excellent toughness in the welding heat affected part comprising 20-35 wt% of Mn, C in the wt% range satisfying 23.6C+Mn>=28 and 33.5C-Mn<=23, Cr in the wt% range satisfying 28.5C+4.4Cr<=57, 5 wt% or less of Cu (exclusive of 0 wt%), 1 wt% or less of Mo, 200 ppm or less of B (all exclusive of 0 wt%), and the remainder consisting of Fe and inevitable impurities. Fine structures of the welding heat affected part contains 96 area % of austenite. Four area % of carbides is contained in an austenitic grain.</p> |
