【摘要】 在碳钢中添加微量合金元素及控温轧(锻)制和冷却得到了较细贝氏体/珠光体双相微合金钢。该钢的组织由直径为2~3μm的平行贝氏体铁素体板条束和等轴块状珠光体构成,还发现贝氏体铁素体内存在点状的合金碳化物析出相。该钢的抗拉强度可达900MPa以上,室温冲击功达47J。随冷却速度的增大,钢中贝氏体量增多,强度提高,韧性稍有降低。更多还原

【Abstract】 By adding microalloying elements into carbon steel and using controlled rolling (forging) and cooling processes,a bainite/pearlite dual-phase microalloyed steel with fine grains was obtained.The results show that the microstructure of this steel consists of isometric massive pearlite and parallel lath-like bainitic ferrite with diameter of 2μm ~3μm.Furthermore,some granule precipitates of microalloyed carbide are found in bainitic ferrite.The tensile strength is more than 900MPa and the Charpy impact energy can reach to 47J at room temperature.With the increase of the cooling rate,both the volume fraction of bainite and the strength of the steel increase,while the toughness of the steel decrease slightly.更多还原