Showing papers by "Yang-Tse Cheng published in 1995"
TL;DR: Amorphous La-Ni thin films over a wide range of composition were fabricated by electron beam evaporation in ultra-high vacuum as discussed by the authors, and the structure and composition of these films were determined by X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron probe microanalysis (EPMA).
43 citations
Patent•
16 Oct 1995TL;DR: A thin film silver-nickel coating for use as a protective coating on electrical terminals of separable electrical connectors is described in this paper, where the volume fraction of nickel significantly influences the fretting wear resistance of the coating, with a preferred nickel content being resulting in the presence of disconnected islands of the nickel phase dispersed within a relatively softer silver matrix.
Abstract: A thin film silver-nickel coating for use as a protective coating on electrical terminals of separable electrical connectors. The silver-nickel coating is a silver-nickel nano-composite material characterized by silver and nickel grains having an average grain size of about five to about fifty nanometers, yielding a silver-rich phase and a harder nickel-rich phase as a result of silver and nickel being immiscible. In accordance with this invention, the volume fraction of nickel significantly influences the fretting wear resistance of the coating, with a preferred nickel content being resulting in the presence of disconnected islands of the nickel phase dispersed within a relatively softer silver matrix.
17 citations
TL;DR: In this article, an optical system for measuring diffusion rates of intercalants in transparent cathode materials was developed and used to measure the diffusivity of lithium in amorphous molybdenum oxide thin films.
3 citations
TL;DR: In this paper, the giant magnetoresistance and oscillatory coupling in epitaxial Fe/Cr(111) multilayers were investigated on hydrogen terminated Si (111) substrates at room temperature by UHV electron beam evaporation.
Abstract: We report on the first studies of the giant magnetoresistance and oscillatory coupling in epitaxial Fe/Cr(111) multilayers. A series of samples were grown on hydrogen terminated Si(111) substrates at room temperature by UHV electron beam evaporation; with the thickness of Fe layer fixed at 30 A, and the thickness of Cr layer varied from 10–47 A. Giant magnetoresistance (GMR) is observed at 4.2 A in these samples, with a maximum value of 13% for a Cr layer thickness of 13 A. The associated oscillatory coupling is comparable to that reported in other crystallographic orientations in terms of both its period and phase.
2 citations
TL;DR: In this paper, the average grain size varies from 10 to 100 nm by choosing an appropriate substrate temperature, and the hardness of the composite is increased four times by reducing the grain-size of both phases from 100 to 10 nm.
Abstract: While gas condensation and mechanical alloying have been used to produce nano-phase powders, an effective method of applying these powders as coatings is still lacking. Furthermore, fundamental studies of the mechanical properties of nano-phase powders may be complicated by the porosity associated with consolidation processes. Recently, we have made nano-crystalline composite thin films of Ag-Mo and Ag-Ni by depositing two immiscible elements simultaneous onto substrates. We found, using XRD and TEM, that the average grain size varies from 10 to 100 nm by choosing an appropriate substrate temperature. Nanoindentation measurements showed the hardness of the composite is increased four times by reducing the grain-size of both phases from 100 to 10 nm. The load vs. displacement curves were simulated using a finite element method (ABAQUS). A relationship between the hardness of the two-phase composite and the yield strength of each phase is obtained.
2 citations
1 citations