The magnetic and structural properties in Co/Cu/Co sandwiches with Ni and Cr buffer layers were investigated. It was found that the coercivity in Ni layer buffered samples decreases with increasing Ni layer thickness,...The magnetic and structural properties in Co/Cu/Co sandwiches with Ni and Cr buffer layers were investigated. It was found that the coercivity in Ni layer buffered samples decreases with increasing Ni layer thickness, while that in Cr layer buffered ones increases with increasing Cr layer thickness, leading to a large difference in field sensitivity of their giant magnetoresistance (GMR) properties. X-ray diffraction and high resolution transmission electron microscope images exhibited that there is a strong fcc (111) texture in the samples with Ni buffer layer. But there are only randomly oriented potycrystalline grains in Cr buffered sandwiches. According to atomic force microscope topography, the surface roughness of Cr buffered sandwiches is smaller than that of Ni buffered ones. It is demonstrated that buffer layer influences both magnetic and structural properties in Co/Cu/Co sandwiches as well as their GMR characteristics.展开更多
A novel surface modification method was proposed to improve the tribological property of Si. Multilayers were grown on Si（100） substrate by self-assembling monolayer （SAMs） method and filtered catholic vacuum arc ...A novel surface modification method was proposed to improve the tribological property of Si. Multilayers were grown on Si（100） substrate by self-assembling monolayer （SAMs） method and filtered catholic vacuum arc （FCVA） technique. The film composition and structure were characterized by using x-ray photoelectron spectroscope （XPS） and Raman spectroscopy （Raman）. Surface morphology and the roughness were also analyzed by an atomic force microscope （AFM） and a scanning electron microscopy （SEM）. The frictional behaviors of the films were evaluated by a UMT tester. Results showed that elastomeric nanocomposite monolayer prepared by SAM was uniformly distributed and isotropy, and the diamond-like carbon （DLC） film was successfully deposited by the FCVA technique. The friction coefficients of the prepared samples were in the range of 0.108-0.188. Furthermore, the friction coefficient slightly increased but the surface quality of the wear trace was improved after adding the copolymer elastomeric macromolecules SEBS on aminopropyl-triethoxysilane （APS） layer due to the inherent long chain of SEBS which abated the immediate impulsion at the interface and changed the kinetic energy into elastic potential energy, and stored it in SEBS.展开更多
对双层钛合金波纹夹芯结构进行2 m/s、4 m/s、6 m/s 3个速度下的落锤冲击试验,获得了冲击过程中接触力、冲头速度、位移和能量吸收情况。此外对同样结构的落锤冲击试验进行有限元模拟,获得了不同速度下的能量吸收效率及波纹夹芯结构各...对双层钛合金波纹夹芯结构进行2 m/s、4 m/s、6 m/s 3个速度下的落锤冲击试验,获得了冲击过程中接触力、冲头速度、位移和能量吸收情况。此外对同样结构的落锤冲击试验进行有限元模拟,获得了不同速度下的能量吸收效率及波纹夹芯结构各部分的能量吸收状况。结果表明:接触力、变形量以及能量吸收与初始冲击速度有密切的关系;计算和有限元模拟结果在峰值力上有一些差距,这是由于计算模型未考虑面板和夹芯层之间脱焊引起的,但在能量吸收方面两种方法结果比较吻合。展开更多
文摘The magnetic and structural properties in Co/Cu/Co sandwiches with Ni and Cr buffer layers were investigated. It was found that the coercivity in Ni layer buffered samples decreases with increasing Ni layer thickness, while that in Cr layer buffered ones increases with increasing Cr layer thickness, leading to a large difference in field sensitivity of their giant magnetoresistance (GMR) properties. X-ray diffraction and high resolution transmission electron microscope images exhibited that there is a strong fcc (111) texture in the samples with Ni buffer layer. But there are only randomly oriented potycrystalline grains in Cr buffered sandwiches. According to atomic force microscope topography, the surface roughness of Cr buffered sandwiches is smaller than that of Ni buffered ones. It is demonstrated that buffer layer influences both magnetic and structural properties in Co/Cu/Co sandwiches as well as their GMR characteristics.
基金Funded by the National Natural Science Foundation of China (Nos.50775101 and 51005103)Key Technology R&D Program of Jiangsu Province (No.BE2009123)+1 种基金Educational Commission of Jiangsu Province (No.09KJB460001)Doctoral Innovation Foundation of Jiangsu University (No.CX07B-03X)
文摘A novel surface modification method was proposed to improve the tribological property of Si. Multilayers were grown on Si（100） substrate by self-assembling monolayer （SAMs） method and filtered catholic vacuum arc （FCVA） technique. The film composition and structure were characterized by using x-ray photoelectron spectroscope （XPS） and Raman spectroscopy （Raman）. Surface morphology and the roughness were also analyzed by an atomic force microscope （AFM） and a scanning electron microscopy （SEM）. The frictional behaviors of the films were evaluated by a UMT tester. Results showed that elastomeric nanocomposite monolayer prepared by SAM was uniformly distributed and isotropy, and the diamond-like carbon （DLC） film was successfully deposited by the FCVA technique. The friction coefficients of the prepared samples were in the range of 0.108-0.188. Furthermore, the friction coefficient slightly increased but the surface quality of the wear trace was improved after adding the copolymer elastomeric macromolecules SEBS on aminopropyl-triethoxysilane （APS） layer due to the inherent long chain of SEBS which abated the immediate impulsion at the interface and changed the kinetic energy into elastic potential energy, and stored it in SEBS.
文摘对双层钛合金波纹夹芯结构进行2 m/s、4 m/s、6 m/s 3个速度下的落锤冲击试验,获得了冲击过程中接触力、冲头速度、位移和能量吸收情况。此外对同样结构的落锤冲击试验进行有限元模拟,获得了不同速度下的能量吸收效率及波纹夹芯结构各部分的能量吸收状况。结果表明:接触力、变形量以及能量吸收与初始冲击速度有密切的关系;计算和有限元模拟结果在峰值力上有一些差距,这是由于计算模型未考虑面板和夹芯层之间脱焊引起的,但在能量吸收方面两种方法结果比较吻合。
