Facile route to bulk ultrafine-grain steels for high strength and ductility.
Facile route to bulk ultrafine-grain steels for high strength and ductility.
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获得高强度和高延展性的大块超细晶粒钢的简易途径。
DOI：
10.1038/s41586-021-03246-3
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发表时间：
2021-03
期刊：
影响因子：
64.8
通讯作者：
Rainforth WM
中科院分区：
文献类型：
--
作者：
Gao J;Jiang S;Zhang H;Huang Y;Guan D;Xu Y;Guan S;Bendersky LA;Davydov AV;Wu Y;Zhu H;Wang Y;Lu Z;Rainforth WM
亚微米晶粒度的钢通常具有高的韧性和强度，这使得它们在轻量化技术和节能策略中具有广阔的应用前景。到目前为止，超细晶(UFG)合金的工业制造一般依赖于扩散相变的操纵，仅限于奥氏体铁素体转变的钢。此外，这些UFG钢有限的加工硬化和均匀的延伸率阻碍了它们的广泛应用。在这里，我们报道了在典型的Fe-22Mn-0.6C TWIP(孪生诱导塑性)钢中，通过少量的铜合金化和通过共格无序富铜相的晶内纳米沉淀(在0.5min内)控制再结晶过程，可以容易地大量产生UFG组织。及时、快速和丰富的纳米沉淀物不仅防止了新鲜再结晶的亚微米颗粒的生长，而且由于其强大和持续的齐纳钉扎效应，大大提高了所获得的UFG结构的热稳定性。重要的是，由于其完全共格和无序的性质，沉淀物与载荷下的位错显示出弱的相互作用。因此，在没有引入脆性颗粒和偏析晶界等有害晶格缺陷的情况下，获得了完全再结晶的UFG结构，其晶粒度为800±400 nm。UFG钢的力学性能显著提高，屈服强度提高了一倍(~710 Mpa)，同时具有高达45%的均匀塑性和高的抗拉强度(~2000 Mpa)。目前的细晶概念可以扩展到其他合金系统，制造工艺也可以很容易地应用到现有的工业生产线上。
Steels with sub-micron grain sizes usually possess high toughness and strength, which makes them promising for light-weighting technologies and energy saving strategies. To date, industrial fabrication of UFG (ultrafine-grained) alloys, which generally relies on the manipulation of diffusional phase transformation, is limited to steels with austenite to ferrite transformation. Moreover, the limited work hardening and uniform elongation of these UFG steels hinder their widespread application. Herein, we report the easy mass production of UFG structures in a typical Fe-22Mn-0.6C TWIP (twinning-induced plasticity) steel via minor Cu alloying and manipulating the recrystallization process by intragranular nanoprecipitation (within 0.5 min) of a coherent disordered Cu-rich phase. The timely rapid and copious nanoprecipitation not only prevents the growth of the freshly recrystallized sub-micron grains, but also substantially enhances thermal stability of the obtained UFG structure due to their strong and sustainable Zener pinning effect. Importantly, the precipitates exhibit weak interactions with dislocations under loading due to their full coherency and disordered nature. Consequently, a fully-recrystallized UFG structure with 800 ± 400 nm grain size was developed without the introduction of any detrimental lattice defects such as brittle particles and segregated boundaries. The resultant mechanical performance is strikingly enhanced, i.e., the yield strength of the UFG steel was doubled (to ~ 710 MPa), with simultaneously large uniform ductility of 45 % and high tensile strength (~ 2000 MPa). The current grain refinement concept can be extended to other alloy systems, and the manufacturing processes can also be readily applied to existing industrial production lines.
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影响因子：
3
作者：
Dini, G.;Najafizadeh, A.;Monir-Vaghefi, S. M.
通讯作者：
Monir-Vaghefi, S. M.
影响因子：
9.4
作者：
Fan, DN;Chen, LQ
通讯作者：
Chen, LQ
影响因子：
3.2
作者：
Gault, Baptiste;Moody, Michael P.;Ringer, Simon P.
通讯作者：
Ringer, Simon P.
影响因子：
56.9
作者：
Chookajorn, Tongjai;Murdoch, Heather A.;Schuh, Christopher A.
通讯作者：
Schuh, Christopher A.
位错和孪晶各自的硬化对孪生塑性钢流变应力的贡献
影响因子：
6
作者：
Liang, Z. Y.;Li, Y. Z.;Huang, M. X.
通讯作者：
Huang, M. X.