Kai Wu
,
Jin-Yu Zhang
,
Gang Liu
,
Jiao Li
,
Guo-Jun Zhang
,
Jun Sun
金属学报(英文版)
doi:10.1007/s40195-016-0375-4
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films (NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be ~5.0 J/m2 for Cu/Cr, ~4.1 J/m2 for Cu/Ta, ~2.8 J/m2 for Cu/Mo, ~1.1 J/m2 for Cu/Nb, and ~1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.
关键词:
niaxial
,
tensile
,
testing
,
Nanostructured
,
multilayer
,
films
,
Flexible
,
substrates
,
Buckling
,
behaviors
,
Adhesion
,
energy
Ya-Qiang Wang
,
Zhao-Qi Hou
,
Jin-Yu Zhang
,
Xiao-Qing Liang
,
Gang Liu
,
Guo-Jun Zhang
,
Jun Sun
金属学报(英文版)
doi:10.1007/s40195-016-0372-7
Cu-Al/Al nanostructured metallic multilayers with Al layer thickness h Al varying from 5 to 100 nm were prepared, and their mechanical properties and deformation behaviors were studied by nanoindentation testing. The results showed that the hardness increased drastically with decreasing h Al down to about 20 nm, whereafter the hardness reached a plateau that approaches the hardness of the alloyed Cu-Al monolithic thin films. The strain rate sensitivity (SRS, m), however, decreased monotonically with reducing h Al. The layer thickness-dependent strengthening mechanisms were discussed, and it was revealed that the alloyed Cu-Al nanolayers dominated at h Al ≤ 20 nm, while the crystalline Al nanolayers dominated at h Al > 20 nm. The plastic deformation was mainly related to the ductile Al nanolayers, which was responsible for the monotonic evolution of SRS with h Al. In addition, the h Al-dependent hardness and SRS were quantitatively modeled in light of the strengthening mechanisms at different length scales.
关键词:
Nanostructured
,
films
,
Cu-Al/Al
,
multilayers
,
Hardness
,
Strain
,
rate
,
sensitivity
,
Layer
,
thickness
,
dependence
景俊海
,
孙青
,
付俊兴
,
孙建成
材料研究学报
用光-CVD 技术,在100—200℃的温度下,在Si 片上淀积出了Si_3N_4薄膜。本文研究了薄膜淀积速率与淀积参数的关系,讨论了淀积的Si_3N_4薄膜的物理性质、化学性质和力学性质。
关键词:
低温
,
Hg sensitizing
,
photo-CVD
,
Si_3N_4
,
films
Li'an HAN
材料科学技术（英）
Lattice effect on magnetic and electrical transport properties of Ln2/3Pb1/3MnO3 (Ln=La, Pr, Nd) films prepared by RF magnetron sputtering technique were investigated. With the decrease of the average ions radius , the structure of Ln2/3Pb1/3MnO3 (Ln=La, Pr, Nd) targets transit from the rhombohedral phase to the orthorhombic phase, and the Curie temperature reduces rapidly with the decrease of . The electrical properties show that films are the metallic state which can be fitted to the formula: ρ(T)= ρ0+ρ1T2+ρ2T4.5 at low temperatures. The temperature range of the ferromagnetic metallic state becomes narrow with the decrease of . The phenomenon can be explained by the lattice effect.
关键词:
Lattice effect
,
films
,
Lattice
,
effect
,
Magn
Journal of Applied Physics
The films with HM=(Pr,Dy)(Fe,Co,Nb,B)(5.5) and SM=Fe, FeCo were prepared by sputtering and subsequent heat treatment. The coercivity of Ti-buffered (Pr,Dy)(Fe,Co,Nb,B)(5.5) single-layer film with 320 nm thickness is as large as 18.8 kOe at room temperature. X-ray diffraction results reveal that the Pr2Fe14B-type phase is randomly oriented in almost all the multilayer films. For the multilayers of Ti(30 nm)/[HM(16 nm)Fe(x nm)]x20/Ti(30 nm)/Si(substrate), the remanence increases and the coercivity decreases with the addition of Fe content, in comparison with the results of the single-layer film and the maximum energy product of 14.8 MGOe is obtained at x=3.0. A noticeable shoulder on the demagnetization curve is observed at low temperatures. When Fe65Co35 is used as the SM component rather than Fe, similar results are found. The enhancement of the magnetic properties in the nanocomposite multilayer films is explained by means of the exchange coupling between the SM and/or HM nanograins of the intra- and interlayers. (C) 2003 American Institute of Physics.
关键词:
films
Applied Optics
Interfacial microstructure tunable photovoltaic effects have been reported in heterojunctions of La(1-x)Ca(x)MnO(3) thin films and tilted or exact cut Nb-doped SrTiO(3) single crystal substrates under irradiation of UV pulsed laser. The photoresponse times of vicinal junctions and films were obviously faster than those of exact cut samples. The behaviors can be explained by the slope of the built-in electric field in the 10 tilted heterojunction and the interfacial terrace microstructure of La(1-x)Ca(x)MnO(3) films. (C) 2011 Optical Society of America
关键词:
films
Chinese Physics Letters
Cu/MgO/La0.9Sr0.1MnO3 pillars are fabricated on SrTiO3 (001) substrates by the micro-fabrication patterning processes. Their electric transport properties have been measured in the temperature range from the temperature smaller than the Curie one to 300K. At 125K there emerges abrupt breaks of output voltage in voltage-current (V-I) curves, corresponding to switching in resistance to metastable states, and finally two closed loops are formed with double threshold biases. Around room temperature the V-I characteristics are non-ohmic and show some gradual hysteresis when sweeping the current in a round-trip scan. A large current-induced resistive change Delta R/R-o, similar to -63.2%, is obtained under a current density of 1.0 x 10(4) Acm(-2). Especially, Delta R/R-0 depends linearly on the applied current and is independent of the applied magnetic field. The current-induced resistive effect should be of interest for various applications such as switching and field effect devices.
关键词:
films
Chinese Physics Letters
The magnetoresistance (MR) behavior of La(2-x/)3Bi(x/3)Ca(1/3)MnO(3) (x = 0.4) compound was investigated. The compound exhibits complex magnetic transitions, i.e., paramagnetic-canted ferromagnetic-ferromagnetic-spin glass transitions. The temperature dependence of resistivity of the compound indicates a semiconducting behavior, and no semiconductor-metal transition was associated with these magnetic transitions. The magnetoresistance ratio exhibits a critical maximum corresponding to the canted ferromagnetic transition. A MR ratio as large as 86% was observed at 85 K. The temperature dependence of MR ratio is well described by the relation of (rho(o)-rho(H))/rho(o) = A(M/M-s)(2).
关键词:
films
Caiyin YOU
材料科学技术（英）
Exchange interaction plays an important role on magnetic properties of nanocomposite magnets consisting of hard- and soft-magnetic phases. Here the exchange interaction in the Sm-Co/Co (and Fe65Co35) magnetic films was characterized by measuring static (mr(H)) and demagnetized (md(H)) remanence curves. According to conventional method: δm(H)=md(H)- [1- 2mr(H)], the exchange interaction was evaluated. The switching fields Hp′ and Hp, at which static (mr(H)) and demagnetized (md(H)) remanence show the fastest change, were identified. The relative ratio of switching fields H0p and Hp has a linear relationship with the maximum value δmmax of δm(H) curves, proposing an alternative way to characterize the exchange interaction.
关键词:
multi-layered films
,
films
,
exchange
,
interaction
