Five universities including Nanjing University of Science and Technology cooperated to publish an article in "Nature"!

Recently, five universities (Jilin University, Xi'an Jiaotong University, University of Sydney, Nanjing University of Science and Technology, and Hong Kong University) have made great achievements in the development of high-performance nanomaterials by controlling the strain hardening behavior of ultra-high-strength nanomaterials by using multi-scale composition fluctuations.
Breakthrough progress
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Published an academic paper titled "Uniting tensile ductility with ultrahigh strength via composition undulation" in the top academic journal Nature
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In this research, Professor Sha Gang and Professor Jin Shenbao from the School of Materials Science and Technology of Nanjing University of Science and Technology cooperated with the team of Associate Professor Han Shuang of Jilin University, Professor Ding Xiangdong, Academician Sun Jun, Professor Ma En and Professor Liao Xiaozhou of Xi'an Jiaotong University.
, mechanical properties experiments, molecular dynamics numerical simulation, and fine electron microscopic analysis, three-dimensional atom probe analysis research was carried out, revealing the existence and complexity of multi-scale composition fluctuations
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The high-performance NiCo single-phase dual-principal solid solution alloy designed and developed in this project realizes the use of composition fluctuations to change the strain hardening behavior of ultra-high strength nano-metal materials
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The combination of 3D atom probe and transmission electron microscope successfully revealed the existence of nanocrystalline grains (grain size 26 nm) and composite nanostructures composed of multi-scale composition fluctuations (1-10 nm) in the material
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The compositional fluctuation causes the obvious fluctuation of the stacking fault energy and lattice strain field, which makes the dislocation motion show the characteristics of hysteresis, intermittent and entanglement, and improves the strain hardening ability of the material
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On the other hand, the viscous slip of dislocation lines enhances the strain rate sensitivity of dislocation motion and improves the strain rate hardening ability
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Under the combined effect of strain hardening and strain rate hardening, the nano-NiCo alloy achieves unprecedented high performance of single-phase face-centered cubic metal: yield strength of 1.
6 GPa, highest tensile strength of nearly 2.
3 GPa, and tensile fracture of 16% strain
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The team of Professor Sha Gang, the co-corresponding author, relies on the three-dimensional atom probe equipment of the Great Nanotechnology Research Institute of Nanjing University of Science and Technology and the school-level analysis and testing center to successfully reveal the nano-NiCo by detecting the three-dimensional spatial distribution information of element atoms in the material.
The multi-scale compositional fluctuations in the alloy and the compositional gradients at the interfaces in different regions provide key experimental support for the molecular dynamics simulation and theoretical calculation of the subsequent interaction between compositional fluctuations and moving dislocations
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This work once again shows that the important role of 3D atom probe technology in the frontier research of materials science is another important research achievement made by the 3D atom probe team of Nanjing University of Science and Technology in the application of atom probe technology
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Since its establishment in 2014, the team has carried out a large number of high-level collaborative research and independent research, and published many important international journals such as Nature, Science, Nature Materials, Nature Communications, Advanced Material, Materials Today, Progress in Materials Science, and Acta Materialia.
A high-quality academic paper
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