采用射频磁控溅射法在Ni基高温合金拉伸件上制备Ni Cr Al Y薄膜应变计。研究了热稳定处理对Ni Cr Al Y薄膜结构、表面形貌的影响,并且测试了Ni Cr Al Y薄膜应变计的电学与应变性能。结果表明:热稳定处理后Ni Cr Al Y薄膜应变计由于在...采用射频磁控溅射法在Ni基高温合金拉伸件上制备Ni Cr Al Y薄膜应变计。研究了热稳定处理对Ni Cr Al Y薄膜结构、表面形貌的影响,并且测试了Ni Cr Al Y薄膜应变计的电学与应变性能。结果表明:热稳定处理后Ni Cr Al Y薄膜应变计由于在表面形成了一层Al2O3膜,具有抗高温氧化的特性,在室温~800℃范围内,应变计电阻同温度呈线性变化,电阻温度系数(TCR)约为290×10^-6/℃,室温下的应变计系数(GF)为2.1。展开更多
Propagation characteristics of surface acoustic waves(SAWs) in ZnO films/glass substrates are theoretically investigated by the three-dimensional(3D) finite element method. At first, for(11ˉ20) ZnO films/glass ...Propagation characteristics of surface acoustic waves(SAWs) in ZnO films/glass substrates are theoretically investigated by the three-dimensional(3D) finite element method. At first, for(11ˉ20) ZnO films/glass substrates, the simulation results confirm that the Rayleigh waves along the [0001] direction and Love waves along the [1ˉ100] direction are successfully excited in the multilayered structures. Next, the crystal orientations of the ZnO films are rotated, and the influences of ZnO films with different crystal orientations on SAW characterizations, including the phase velocity, electromechanical coupling coefficient, and temperature coefficient of frequency, are investigated. The results show that at appropriate h/λ, Rayleigh wave has a maximum k^2 of 2.4% in(90°, 56.5°, 0°) ZnO film/glass substrate structure; Love wave has a maximum k^2 of 3.81% in(56°, 90°, 0°) ZnO film/glass substrate structure. Meantime, for Rayleigh wave and Love wave devices, zero temperature coefficient of frequency(TCF) can be achieved at appropriate ratio of film thickness to SAW wavelength. These results show that SAW devices with higher k^2 or lower TCF can be fabricated by flexibly selecting the crystal orientations of ZnO films on glass substrates.展开更多
文摘采用射频磁控溅射法在Ni基高温合金拉伸件上制备Ni Cr Al Y薄膜应变计。研究了热稳定处理对Ni Cr Al Y薄膜结构、表面形貌的影响,并且测试了Ni Cr Al Y薄膜应变计的电学与应变性能。结果表明:热稳定处理后Ni Cr Al Y薄膜应变计由于在表面形成了一层Al2O3膜,具有抗高温氧化的特性,在室温~800℃范围内,应变计电阻同温度呈线性变化,电阻温度系数(TCR)约为290×10^-6/℃,室温下的应变计系数(GF)为2.1。
基金supported by the National Natural Science Foundation of China(Grant No.11304160)the Natural Science Foundation of Jiangsu Provincial Higher Education Institutions,China(Grant No.13KJB140008)the Foundation of Nanjing University of Posts and Telecommunications,China(Grant No.NY213018)
文摘Propagation characteristics of surface acoustic waves(SAWs) in ZnO films/glass substrates are theoretically investigated by the three-dimensional(3D) finite element method. At first, for(11ˉ20) ZnO films/glass substrates, the simulation results confirm that the Rayleigh waves along the [0001] direction and Love waves along the [1ˉ100] direction are successfully excited in the multilayered structures. Next, the crystal orientations of the ZnO films are rotated, and the influences of ZnO films with different crystal orientations on SAW characterizations, including the phase velocity, electromechanical coupling coefficient, and temperature coefficient of frequency, are investigated. The results show that at appropriate h/λ, Rayleigh wave has a maximum k^2 of 2.4% in(90°, 56.5°, 0°) ZnO film/glass substrate structure; Love wave has a maximum k^2 of 3.81% in(56°, 90°, 0°) ZnO film/glass substrate structure. Meantime, for Rayleigh wave and Love wave devices, zero temperature coefficient of frequency(TCF) can be achieved at appropriate ratio of film thickness to SAW wavelength. These results show that SAW devices with higher k^2 or lower TCF can be fabricated by flexibly selecting the crystal orientations of ZnO films on glass substrates.