Special Steel department of Central Iron and Steel Research Institute (CISRI), Beijing 100081, China.
School of Aeronautics and Astronautics, Sichuan University, Chengdu 610065, China.
Sci Rep. 2017 Feb 2;7:41459. doi: 10.1038/srep41459.
Strength and toughness are a couple of paradox as similar as strength-ductility trade-off in homogenous materials, body-centered-cubic steels in particular. Here we report a simple way to get ultrahigh toughness without sacrificing strength. By simple alloying design and hot rolling the 5Mn3Al steels in ferrite/austenite dual phase temperature region, we obtain a series of ferrite/martensite laminated steels that show up-to 400-450J Charpy V-notch impact energy combined with a tensile strength as high as 1.0-1.2 GPa at room temperature, which is nearly 3-5 times higher than that of conventional low alloy steels at similar strength level. This remarkably enhanced toughness is mainly attributed to the delamination between ferrite and martensite lamellae. The current finding gives us a promising way to produce high strength steel with ultrahigh impact toughness by simple alloying design and hot rolling in industry.
强度和韧性是一对矛盾体，就像同素异形体中的强度-延展性权衡一样，体心立方钢尤其如此。在这里，我们报告了一种在不牺牲强度的情况下获得超高韧性的简单方法。通过简单的合金设计和在铁素体/奥氏体双相温度区热轧，我们获得了一系列铁素体/马氏体层状钢，其夏比 V 型缺口冲击能高达 400-450J，室温下的拉伸强度高达 1.0-1.2 GPa，几乎比类似强度水平的传统低合金钢高 3-5 倍。这种显著增强的韧性主要归因于铁素体和马氏体层之间的分层。目前的发现为我们提供了一种通过简单的合金设计和热轧在工业上生产高强度超高冲击韧性钢的有前途的方法。
