Fe3O4/T-ZnOw composites are fabricated by depositing a layer of Fe3O4 film on the surface of tetrapod-shaped ZnO whisker （T-ZnOw） by ferrite plating method. The morphology, structure and magnetic properties of the c...Fe3O4/T-ZnOw composites are fabricated by depositing a layer of Fe3O4 film on the surface of tetrapod-shaped ZnO whisker （T-ZnOw） by ferrite plating method. The morphology, structure and magnetic properties of the composites are characterized by scanning electron microscopy （SEM）, X-ray diffractometer （XRD） and vibrating-sample magnetometer （VSM）, respectively. The effects of temperature and pH value of fertile plating on the Fe3O4/T-ZnOw composites and the magnetic properties of composites are studied. It is shown that the chemical enviromnent with pH value at 7.5 is most favorable for the ferrite plating processes by analyzing the main peaks intensity of Fe3O4 in the XRD patterns and the average diameters of the Fe3O4 crystalline. The increase of the ferrite plating temperature with pH value around 7.5 benefits the whole encapsulation of T-ZnOw by the Fe3O4 magnetic films. The composites exhibit ferromagnetic properties and show much lower magnetization intensity than bulk samples at the same magnetic field intensity.展开更多
The influence of hot rolling on the microstructure and subsequent mechanical characteristics of explosive-welded ferritic stainless steel （FSS）/carbon steel （CS） laminate was investigated. The results indicate tha...The influence of hot rolling on the microstructure and subsequent mechanical characteristics of explosive-welded ferritic stainless steel （FSS）/carbon steel （CS） laminate was investigated. The results indicate that by hot rolling, decarburization layer disappears and a uniform structure is gained in CS side, but ferrite grains and carbides in constituent FSS form an uneven band microstructure which is denser at superficial zone than near the interface. The transmission electron microscopy results indicate that the layers adhering to the interface show typical deformed microstructure features, i.e., stream-like strips and elongated grains in FSS plates, carbide precipitates and bended cementite fragments in CS plates; and high-density dislocations in both plates, With hot rolling, various mechanical strengths and hardness are increased, while the elongation percentage is diminished. Examination of fractographs from tensile tests reveals predominately small dimples for explosive-welded specimens, whereas both big dimples and cleavage fracture for rolled specimens. Stereomicroscopic fractographs taken on shear samples indicate that the surfaces of explosive-welded specimens exhibit uniform deformation, but uneven deformation is displayed for that of rolled specimens. These results indicate that hot rolling is beneficial to improve the strength of explosive-welded FSS/CS laminate but not good for enhancing its plasticity.展开更多
基金National Natural Science Foundation of China(51001007)Fundamental Research Funds for the Central Universities
文摘Fe3O4/T-ZnOw composites are fabricated by depositing a layer of Fe3O4 film on the surface of tetrapod-shaped ZnO whisker （T-ZnOw） by ferrite plating method. The morphology, structure and magnetic properties of the composites are characterized by scanning electron microscopy （SEM）, X-ray diffractometer （XRD） and vibrating-sample magnetometer （VSM）, respectively. The effects of temperature and pH value of fertile plating on the Fe3O4/T-ZnOw composites and the magnetic properties of composites are studied. It is shown that the chemical enviromnent with pH value at 7.5 is most favorable for the ferrite plating processes by analyzing the main peaks intensity of Fe3O4 in the XRD patterns and the average diameters of the Fe3O4 crystalline. The increase of the ferrite plating temperature with pH value around 7.5 benefits the whole encapsulation of T-ZnOw by the Fe3O4 magnetic films. The composites exhibit ferromagnetic properties and show much lower magnetization intensity than bulk samples at the same magnetic field intensity.
基金This research was funded by the National Natural Science Foundation of China under Grant No. U 1510131, the Key Research and Development Program of Shanxi Province under Grant Nos. 201603D121010 and 201603D111004 and Shanxi Young Scholars Program.
文摘The influence of hot rolling on the microstructure and subsequent mechanical characteristics of explosive-welded ferritic stainless steel （FSS）/carbon steel （CS） laminate was investigated. The results indicate that by hot rolling, decarburization layer disappears and a uniform structure is gained in CS side, but ferrite grains and carbides in constituent FSS form an uneven band microstructure which is denser at superficial zone than near the interface. The transmission electron microscopy results indicate that the layers adhering to the interface show typical deformed microstructure features, i.e., stream-like strips and elongated grains in FSS plates, carbide precipitates and bended cementite fragments in CS plates; and high-density dislocations in both plates, With hot rolling, various mechanical strengths and hardness are increased, while the elongation percentage is diminished. Examination of fractographs from tensile tests reveals predominately small dimples for explosive-welded specimens, whereas both big dimples and cleavage fracture for rolled specimens. Stereomicroscopic fractographs taken on shear samples indicate that the surfaces of explosive-welded specimens exhibit uniform deformation, but uneven deformation is displayed for that of rolled specimens. These results indicate that hot rolling is beneficial to improve the strength of explosive-welded FSS/CS laminate but not good for enhancing its plasticity.
