Abstract
Here, two types of gradient structures (GS), i.e. gradient dislocation structure (GDS) and gradient grain structure (GGS) are successfully constructed . Results indicate that the relationship between the strength and ductility of the samples with GDS and GGS is referred to as an inverse linear rule, which is in stark contrast to and superior to the banana-shaped strength-ductility trade-off dilemma in monolithic materials. In low-strength (σy∼400–550 MPa) range, plausible strength-ductility-toughness synergies can be achieved by both the GDS and GGS, however, in high-strength (σy∼550–750 MPa) range, much better strength-ductility-toughness combinations are presented by the GGS than those by the GDS. For the GGS, the formation of strong 〈110〉 fibre texture in the tensile direction is beneficial for enhancing the high strength-ductility-toughness synergy.
Acknowledgements
We acknowledge support by the National Natural Science Foundation of China (No. U20A20272, 51874114, 51804095) and Natural Science Foundation of Hebei Province (Nos. E2020402076, E2021402002, ZD2020195, ZD2021020) and Handan Scientific Research Program (21122015004, 21422111241).
Disclosure statement
No potential conflict of interest was reported by the author(s).