Sputter-deposited Au/NisoFeso bilayer films were annealed in a vacuum of 5×10^-4 Pa at 523 to 723 K for 30 or 90 min. The characteristics of the bilayer films were determined by Auger electron spectroscopy, field...Sputter-deposited Au/NisoFeso bilayer films were annealed in a vacuum of 5×10^-4 Pa at 523 to 723 K for 30 or 90 min. The characteristics of the bilayer films were determined by Auger electron spectroscopy, field emission scanning electron microscopy, X- ray diffractometry, a four-point probe technique, and an alternating gradient magnetometer. When the annealing temperature and time reached 723 K and 90 min, Ni and Fe atoms markedly diffused into the Au layer. The grain size of the Au layer did not change markedly with the annealing condition. As the annealing time was 30 min and the annealing temperature exceeded 573 K, the resistance of the bilayer film increased with increasing the annealing temperature. Furthermore, the resistance of the bilayer film annealed at 723 K for 90 ,nin was lower than that of the bilayer film annealed at 723 K for 30 min. All the bilayer films showed magnetic hysteresis loops. The as-deposited bilayer film showed a hard magnetization. The bilayer film represented an easy magnetization with increasing the annealing temperature. The Au/Ni50Fe50 film that annealed at 723 K for 90 min had the lowest saturation magnetization.展开更多
The microstructures, the phase transformation characteristics, and the mechanical properties of the Ti50Ni47Fe3 alloy in as-forged and as-cross-rolled states were investigated. It is found that, after cross-rolling, t...The microstructures, the phase transformation characteristics, and the mechanical properties of the Ti50Ni47Fe3 alloy in as-forged and as-cross-rolled states were investigated. It is found that, after cross-rolling, the phase transformation temperature （Ms） of the alloy decreases drastically and the grains get refined. Moreover, its yield strength and fracture strength after cross-rolling hit 540 MPa and 687 MPa respectively, up by about 200 MPa over those in as-forged state.展开更多
The detailed microstructures of Ni80Fe20/Fe50Mn50 superlattices have been characterized using both x-ray diffraction techniques and transmission electron microscopy.The obrivous layered structure,typical column struct...The detailed microstructures of Ni80Fe20/Fe50Mn50 superlattices have been characterized using both x-ray diffraction techniques and transmission electron microscopy.The obrivous layered structure,typical column structure and twins which exist in Ni80Fe20/Fe50Mn50 superlattices were observed through performing transmission microscopy.By combining the technique of lowangle x-ray reflectivity(specular and off-specular scans)with the anomalous scattering effect and high-angle x-ray diffraction(using conventional x-ray),wequantitatively analysed the microstructural variation as a function of annealing temperature.It is found that the lateral correlation length,the(111)peak intensity of the superlattices and the average multilayer coherence length all increase with a rise in annealing temperature annealing can decrease the rootmean-square roughness at the interfaces of Ni80Fe20/Fe50Mn50 superlattices.the obtained microstructural knowledge will be helpful in understanding the magnetic properties of the ni80Fe20/Fe50Mn50 exchange bias system.展开更多
The mechanical behavior and the effect of pre-strain on recovery behavior of Ti50Ni47Fe3 (at. pct) alloy were investigated systematically by tensile and recovered tests accompanied by electrical resistance measurement...The mechanical behavior and the effect of pre-strain on recovery behavior of Ti50Ni47Fe3 (at. pct) alloy were investigated systematically by tensile and recovered tests accompanied by electrical resistance measurement. Ti50Ni47Fe3 alloy has different deformation behaviors at different temperature ranges, the deformation curves in different temperature range can be classified into four kinds. The start temperature of recovery increases with the increase of pre-strain. There exists an optimal deformation condition, at which the specimen exhibits maximum free recovery strain. With increasing pre-strain the recovery stress increases and reaches the maximum at 8% pre-strain. R-phase to parent transition offered about 0.2% recovery strain. With pre-strain increasing the recovery stress increases and reaches to the maximum at 8% pre-strain. The recovery stress is corresponding with the critical stress of stress-induced martensitic transformation.展开更多
文摘Sputter-deposited Au/NisoFeso bilayer films were annealed in a vacuum of 5×10^-4 Pa at 523 to 723 K for 30 or 90 min. The characteristics of the bilayer films were determined by Auger electron spectroscopy, field emission scanning electron microscopy, X- ray diffractometry, a four-point probe technique, and an alternating gradient magnetometer. When the annealing temperature and time reached 723 K and 90 min, Ni and Fe atoms markedly diffused into the Au layer. The grain size of the Au layer did not change markedly with the annealing condition. As the annealing time was 30 min and the annealing temperature exceeded 573 K, the resistance of the bilayer film increased with increasing the annealing temperature. Furthermore, the resistance of the bilayer film annealed at 723 K for 90 ,nin was lower than that of the bilayer film annealed at 723 K for 30 min. All the bilayer films showed magnetic hysteresis loops. The as-deposited bilayer film showed a hard magnetization. The bilayer film represented an easy magnetization with increasing the annealing temperature. The Au/Ni50Fe50 film that annealed at 723 K for 90 min had the lowest saturation magnetization.
文摘The microstructures, the phase transformation characteristics, and the mechanical properties of the Ti50Ni47Fe3 alloy in as-forged and as-cross-rolled states were investigated. It is found that, after cross-rolling, the phase transformation temperature （Ms） of the alloy decreases drastically and the grains get refined. Moreover, its yield strength and fracture strength after cross-rolling hit 540 MPa and 687 MPa respectively, up by about 200 MPa over those in as-forged state.
文摘The detailed microstructures of Ni80Fe20/Fe50Mn50 superlattices have been characterized using both x-ray diffraction techniques and transmission electron microscopy.The obrivous layered structure,typical column structure and twins which exist in Ni80Fe20/Fe50Mn50 superlattices were observed through performing transmission microscopy.By combining the technique of lowangle x-ray reflectivity(specular and off-specular scans)with the anomalous scattering effect and high-angle x-ray diffraction(using conventional x-ray),wequantitatively analysed the microstructural variation as a function of annealing temperature.It is found that the lateral correlation length,the(111)peak intensity of the superlattices and the average multilayer coherence length all increase with a rise in annealing temperature annealing can decrease the rootmean-square roughness at the interfaces of Ni80Fe20/Fe50Mn50 superlattices.the obtained microstructural knowledge will be helpful in understanding the magnetic properties of the ni80Fe20/Fe50Mn50 exchange bias system.
文摘The mechanical behavior and the effect of pre-strain on recovery behavior of Ti50Ni47Fe3 (at. pct) alloy were investigated systematically by tensile and recovered tests accompanied by electrical resistance measurement. Ti50Ni47Fe3 alloy has different deformation behaviors at different temperature ranges, the deformation curves in different temperature range can be classified into four kinds. The start temperature of recovery increases with the increase of pre-strain. There exists an optimal deformation condition, at which the specimen exhibits maximum free recovery strain. With increasing pre-strain the recovery stress increases and reaches the maximum at 8% pre-strain. R-phase to parent transition offered about 0.2% recovery strain. With pre-strain increasing the recovery stress increases and reaches to the maximum at 8% pre-strain. The recovery stress is corresponding with the critical stress of stress-induced martensitic transformation.
