To investigate potential strengthening approaches,multi-layered zirconium–titanium(Zr-Ti)composites were fabricated by hot-rolling bonding and annealing.The microstructures of these composites were characterized usin...To investigate potential strengthening approaches,multi-layered zirconium–titanium(Zr-Ti)composites were fabricated by hot-rolling bonding and annealing.The microstructures of these composites were characterized using scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS)and electron backscatter diffractometry(EBSD).Their mechanical properties were evaluated by uniaxial tension and compression measurements.It was found that the fabricated Zr–Ti composites are composed of alternating Zr/diffusion/Ti layers,and chemical compositions of Zr and Ti showed a gradient distribution in the diffusion layer.Compared with as-rolled samples,annealing can strengthen the layered gradient Zr–Ti composite,and this is mainly caused by solid-solution strengthening and microstructure refinement-induced strengthening.Compared with the raw materials,a synergistic improvement of strength and ductility is achieved in the Zr–Ti composite as a result of the layered gradient microstructure.Tension–compression asymmetry is observed in the Zr–Ti composites,which may be attributed to twinning and microvoids induced by unbalanced diffusion.展开更多
The microstructure,diffusional and mechanical bonding behavior and microhardness distribution of laminated composites fabricated by ECAP process were investigated.Al?Cu and Cu?Ni laminated composites were produced by ...The microstructure,diffusional and mechanical bonding behavior and microhardness distribution of laminated composites fabricated by ECAP process were investigated.Al?Cu and Cu?Ni laminated composites were produced by ECAP process up to4passes at room temperature and high temperature(300°C).The results of microstructure characterization by SEM and shear strength test revealed that the joints between the layers of4-pass ECAPed samples were considerably stronger than those of1-pass ECAPed samples due to tolerating higher values of plastic deformations during ECAP.Furthermore,shear strength data showed that increasing ECAP temperature caused a notable increase in shear strength of the specimens.The reason lies in the formation of diffusional joint between the interface of both Al/Cu and Cu/Ni layers at high temperature.The shear bonding strength of ECAPed Cu/Ni/Cu composite at high temperature was remarkably higher than that of ECAPed Cu/Al/Cu composite.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51971041)the Natural Science Foundation of Chongqing,China(No.cstc2019jcyj-msxm X0234)。
文摘To investigate potential strengthening approaches,multi-layered zirconium–titanium(Zr-Ti)composites were fabricated by hot-rolling bonding and annealing.The microstructures of these composites were characterized using scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS)and electron backscatter diffractometry(EBSD).Their mechanical properties were evaluated by uniaxial tension and compression measurements.It was found that the fabricated Zr–Ti composites are composed of alternating Zr/diffusion/Ti layers,and chemical compositions of Zr and Ti showed a gradient distribution in the diffusion layer.Compared with as-rolled samples,annealing can strengthen the layered gradient Zr–Ti composite,and this is mainly caused by solid-solution strengthening and microstructure refinement-induced strengthening.Compared with the raw materials,a synergistic improvement of strength and ductility is achieved in the Zr–Ti composite as a result of the layered gradient microstructure.Tension–compression asymmetry is observed in the Zr–Ti composites,which may be attributed to twinning and microvoids induced by unbalanced diffusion.
文摘The microstructure,diffusional and mechanical bonding behavior and microhardness distribution of laminated composites fabricated by ECAP process were investigated.Al?Cu and Cu?Ni laminated composites were produced by ECAP process up to4passes at room temperature and high temperature(300°C).The results of microstructure characterization by SEM and shear strength test revealed that the joints between the layers of4-pass ECAPed samples were considerably stronger than those of1-pass ECAPed samples due to tolerating higher values of plastic deformations during ECAP.Furthermore,shear strength data showed that increasing ECAP temperature caused a notable increase in shear strength of the specimens.The reason lies in the formation of diffusional joint between the interface of both Al/Cu and Cu/Ni layers at high temperature.The shear bonding strength of ECAPed Cu/Ni/Cu composite at high temperature was remarkably higher than that of ECAPed Cu/Al/Cu composite.