首页>
外国专利>
Fine Grain Type Steel Having Superior Toughness in Weld Heat Affected Zone and Method for Manufacturing the Same
Fine Grain Type Steel Having Superior Toughness in Weld Heat Affected Zone and Method for Manufacturing the Same
展开▼
机译:在焊接热影响区具有优异韧性的细晶粒型钢及其制造方法
展开▼
页面导航
摘要
著录项
相似文献
摘要
PURPOSE: A fine grain type ferritic steel for welded structure having superior toughness in weld heat affected zone is provided to improve toughness of the weld heat affected zone by uniformly distributing fine TiN precipitate and Ti-Nb composite precipitate on base metal as increasing fine ferrite phase fraction, and a method for manufacturing the same are provided. CONSTITUTION: The method for manufacturing fine grain type ferritic steel for welded structure having superior toughness in weld heat affected zone comprises the processes of heating a steel slab comprising 0.02 to 0.18 wt.% of C, 0.05 to 0.5 wt.% of Si, 0.4 to 2.0 wt.% of Mn, 0.005 to 0.2 wt.% of Ti, 0.005 to 0.1 wt.% of Al, 0.008 to 0.030 wt.% of N, 0.0003 to 0.01 wt.% of B, 0.03 wt.% or less of P, 0.03 wt.% or less of S, 0.005 wt.% or less of O, 1.2=Ti/N=2.5, 10=N/B=40, 2.5=Al/N=7, 0.3=Nb/N=9, 7=(Ti+2Al+4B+Nb)/N=17 and a balance of Fe and other impurities in the temperature range of 1,000 to 1,150 deg.C for 60 to 180 minutes; cooling the heated steel slab to the austenite non-recrystallization temperature range of 880 to 930 deg.C at a cooling rate of 10 to 20 deg.C/sec by controlling size of austenite grains to 20 m or less; rolling the cooled steel slab to a reduction ratio of 50% or more, and hot rolling the rolled steel sheet to a rolling ratio of 40% or more in the two-phase ferrite and austenite region temperature range of 740 to 780 deg.C at a cooling rate of 5 to 15 deg.C/sec; and cooling the hot rolled steel sheet to an ordinary temperature at a cooling rate of 5 to 20 deg.C/sec.
展开▼
机译:目的:提供一种在焊接热影响区具有优异韧性的用于焊接结构的细晶粒型铁素体钢,以通过增加细小的铁素体相而均匀地在母材上均匀分布TiN沉淀物和Ti-Nb复合沉淀物来提高焊接热影响区的韧性。本发明提供一种馏分及其制造方法。构成:一种在焊接热影响区具有优异韧性的用于焊接结构的细晶粒型铁素体钢的制造方法,包括以下步骤:加热包含0.02%至0.18%(重量)的C,0.05%至0.5%(重量)的Si,0.4% Mn至2.0重量%,Ti 0.005至0.2重量%,Al 0.005至0.1重量%,N 0.008至0.030重量%,B 0.0003至0.01重量%,0.03重量%以下P,0.03重量%或更少的S,0.005重量%或更少的O,1.2 <= Ti / N <= 2.5、10 <= N / B <= 40、2.5 <= Al / N <= 7 ,0.3 <= Nb / N <= 9、7 <=(Ti + 2Al + 4B + Nb)/ N <= 17以及剩余的Fe和其他杂质在1,000至1,150℃的温度范围内保持60至180分钟;通过将奥氏体晶粒的尺寸控制在20m以下,以10〜20℃/秒的冷却速度将加热后的钢坯冷却至880〜930℃的奥氏体非再结晶温度范围。在740〜780℃的两相铁素体和奥氏体区域温度范围内,将冷却后的钢坯轧制至压下率为50%以上,并且将轧制钢板热轧至轧制率为40%以上。冷却速度为5至15℃/秒;将热轧钢板以5〜20℃/秒的冷却速度冷却至常温。
展开▼