Achieving High Strength and Tensile Ductility in Pure Nickel by Cryorolling with Subsequent Low-Temperature Short-Time Annealing  

作　　者：Zhide Li Hao Gu Kaiguang Luo Charlie Kong Hailiang Yu 

机构地区：[1]Light Alloys Research Institute,Central South University,Changsha 410083,China [2]State Key Laboratory of High Performance Complex Manufacturing,Central South University,Changsha 410083,China [3]College of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China [4]Electron Microscope Unit,University of New South Wales,Sydney,NSW 2052,Australia

出　　处：《Engineering》2024年第2期190-203,共14页工程（英文）

基　　金：the financial support from the High-Tech Industry Technology Innovation Leading Plan of Hunan Province,China(2020GK2032);the Innovation Driven Program of Central South University(CSU)(2019CX006);the Research Fund of the Key Laboratory of High Performance Complex Manufacturing at CSU。

摘　　要：Ultra fine-grained pure metals and their alloys have high strength and low ductility.In this study,cryorolling under different strains followed by low-temperature short-time annealing was used to fabricate pure nickel sheets combining high strength with good ductility.The results show that,for different cryorolling strains,the uniform elongation was greatly increased without sacrificing the strength after annealing.A yield strength of 607 MPa and a uniform elongation of 11.7%were obtained after annealing at a small cryorolling strain(ε=0.22),while annealing at a large cryorolling strain(ε=1.6)resulted in a yield strength of 990 MPa and a uniform elongation of 6.4%.X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning electron microscopy(SEM),and electron backscattered diffraction(EBSD)were used to characterize the microstructure of the specimens and showed that the high strength could be attributed to strain hardening during cryorolling,with an additional contribution from grain refinement and the formation of dislocation walls.The high ductility could be attributed to annealing twins and micro-shear bands during stretching,which improved the strain hardening capacity.The results show that the synergistic effect of strength and ductility can be regulated through low-temperature short-time annealing with different cryorolling strains,which provides a new reference for the design of future thermo-mechanical processes.

关 键 词：CRYOROLLING ANNEALING NICKEL Strain hardening DUCTILITY 

分 类 号：TG14[一般工业技术—材料科学与工程]