用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加;...用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加; 平均位错分布参量基本不变。由位错密度及位错分布参量计算得到 NiTi 薄膜材料的显微硬度值,随固溶时间的增加,显微硬度计算值明显低于测量值。展开更多
The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si （100） substrates by DC magnetron sputtering was studied by nanoindentation.NiTi films were deposited ...The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si （100） substrates by DC magnetron sputtering was studied by nanoindentation.NiTi films were deposited at two substrate temperatures viz.300 and 400 ℃.NiTi films deposited at 300 ℃ were annealed for 4 h at four different temperatures,i.e.300,400,500 and 600 C whereas films deposited at 400 ℃ were annealed for 4 h at three different temperatures,i.e.400,500 and 600 ℃.The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate temperatures.For a given substrate temperature,the hardness and elastic modulus were found to remain unchanged as long as the films were amorphous.However,both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become crystalline.The results were explained on the basis of the change in microstructure of the film with change in annealing temperature.展开更多
The superelastic properties of NiTi thin films prepared with sputtering were studied. To characterize their superelasticity, tensile and bulging and indentation tests were performed. The measured mechanisms using thes...The superelastic properties of NiTi thin films prepared with sputtering were studied. To characterize their superelasticity, tensile and bulging and indentation tests were performed. The measured mechanisms using these three methods were compared, and the factors that influence superelasticity were described.展开更多
Local annealing of amorphous NiTi thin films was performed by using an Nd：YAG 1064 nm wavelength pulsed laser beam. Raw samples produced by simultaneous sputter deposition from elemental Ni and Ti targets onto unheat...Local annealing of amorphous NiTi thin films was performed by using an Nd：YAG 1064 nm wavelength pulsed laser beam. Raw samples produced by simultaneous sputter deposition from elemental Ni and Ti targets onto unheated Si （100） and Silica （111） substrates were used for annealing. Delicate treatment with 15.92 W/mm^2 power density resulted in crystallization of small spots; while 16.52 and 17.51 W/mm^2 power densities caused ablation of the amorphous layer. Optical microscopy, scanning electron microscopy, X-ray diffraction and atomic force microscopy were performed to characterize the microstructure and surface morphology of the amorphous/crystallized spot patterns.展开更多
使用模具并采用磁控溅射法在铁电陶瓷PZT基体上沉积具有条形分布结构的Ni Ti SMA薄膜。显微组织结构观察发现,以条形分布结构方式沉积的Ni Ti SMA薄膜晶化处理后具有等轴晶结构。比较所制备PZT/Ni-Ti SMA薄膜复合材料与纯PZT的介电常数...使用模具并采用磁控溅射法在铁电陶瓷PZT基体上沉积具有条形分布结构的Ni Ti SMA薄膜。显微组织结构观察发现,以条形分布结构方式沉积的Ni Ti SMA薄膜晶化处理后具有等轴晶结构。比较所制备PZT/Ni-Ti SMA薄膜复合材料与纯PZT的介电常数及介电损耗发现,两者的介电损耗水平接近;复合材料的介电常数比纯PZT的提高约18%。Ni Ti SMA的沉积使基体中靠近薄膜区域的Zr/Ti物质的量比恰好落在准同型相界区内,致使所制备复合材料的介电性能优于纯PZT。展开更多
文摘用磁控溅射法将 NiTi 薄膜沉积在纯 Cu 箔片上,在 800℃分别固溶 30 min,45 min,60 min 和 120 min;采用X 射线傅氏线形分析法计算各固溶时间的位错密度及位错分布参量。随固溶时间的增加,平均位错密度不断下降; 亚晶粒尺寸 D 逐渐增加; 平均位错分布参量基本不变。由位错密度及位错分布参量计算得到 NiTi 薄膜材料的显微硬度值,随固溶时间的增加,显微硬度计算值明显低于测量值。
基金the support of Defence Research Development Organization under Project DMR-275the support of the National Program on Smart Materials (NPSM)
文摘The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si （100） substrates by DC magnetron sputtering was studied by nanoindentation.NiTi films were deposited at two substrate temperatures viz.300 and 400 ℃.NiTi films deposited at 300 ℃ were annealed for 4 h at four different temperatures,i.e.300,400,500 and 600 C whereas films deposited at 400 ℃ were annealed for 4 h at three different temperatures,i.e.400,500 and 600 ℃.The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate temperatures.For a given substrate temperature,the hardness and elastic modulus were found to remain unchanged as long as the films were amorphous.However,both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become crystalline.The results were explained on the basis of the change in microstructure of the film with change in annealing temperature.
文摘The superelastic properties of NiTi thin films prepared with sputtering were studied. To characterize their superelasticity, tensile and bulging and indentation tests were performed. The measured mechanisms using these three methods were compared, and the factors that influence superelasticity were described.
文摘Local annealing of amorphous NiTi thin films was performed by using an Nd：YAG 1064 nm wavelength pulsed laser beam. Raw samples produced by simultaneous sputter deposition from elemental Ni and Ti targets onto unheated Si （100） and Silica （111） substrates were used for annealing. Delicate treatment with 15.92 W/mm^2 power density resulted in crystallization of small spots; while 16.52 and 17.51 W/mm^2 power densities caused ablation of the amorphous layer. Optical microscopy, scanning electron microscopy, X-ray diffraction and atomic force microscopy were performed to characterize the microstructure and surface morphology of the amorphous/crystallized spot patterns.
文摘使用模具并采用磁控溅射法在铁电陶瓷PZT基体上沉积具有条形分布结构的Ni Ti SMA薄膜。显微组织结构观察发现,以条形分布结构方式沉积的Ni Ti SMA薄膜晶化处理后具有等轴晶结构。比较所制备PZT/Ni-Ti SMA薄膜复合材料与纯PZT的介电常数及介电损耗发现,两者的介电损耗水平接近;复合材料的介电常数比纯PZT的提高约18%。Ni Ti SMA的沉积使基体中靠近薄膜区域的Zr/Ti物质的量比恰好落在准同型相界区内,致使所制备复合材料的介电性能优于纯PZT。
