Papers by Keyword: High Conductivity

Abstract: High-strength and high-conductivity copper alloy is a kind of structural function materials, which has excellent comprehensive mechanical and physical properties. The strengthening methods of copper alloy are summarized. The basic requirements of high-strength and high-conductivity copper alloy is established. The application of the materials is described, including lead frame materials, electrified contact wires materials, electrode Materials. Meanwhile, the alumina dispersion strengthened copper alloy is introduced. The internal oxidation process, structure, dispersoid and anti-intenerate properties have also been analysis in detail. Finally, the development direction of this material is put forward.

Abstract: High conductive and polymer composite has good electrical, mechanical and electrochemical properties which is a scalable, multi-functional composite material. It is widely used in electric vehicles, power storage and military fields. This article treats graphene as the working electrode self-supporting film and prepares the structures of the reduction of graphene-polypyrrole-Sulfonated graphene three-layer composite membrane using Polypyrrole electrochemical deposition method. From the electricity microscope, we can observe that the composite film have a closely structure which improves the electrical conductivity and mechanical properties of highly conductive polymer material. Finally, this paper studies the electrical properties of the composite film by the way of electrical experiment. From the experiment, we can conclude that in the voltage driver of 1V, the composite film has a better driving performance which can reach a rate of 198 / s. Its cycle life is up to 8000 times. This provides a new method for preparation and study of graphene conductive polymer composite.

Abstract: The aging behavior of Cu-0.39Cr-0.11Zr-0.12Y alloy was investigated in this paper. The results showed that the tested alloy could obtain higher electrical conductivity and microhardness in solution at 960 °C for 1 hour under various deformations and aging at 480 °C condition than that of the alloy in solution-aged condition. The strength of the tested alloy increased with the increased deformation by cold working, the highest tensile strength value reached 637 MPa, while the elongation and electrical conductivity dropped a little. The values of tensile strength, electrical conductivity and elongation were 603 MPa, 79.66%IACS and 9.8% respectively when the second pulling deformation increased to 75.0%, that would meet the requirement of contract wire used in electrical high-speed railway.

Abstract: The development trend for diagnostics is reducing the diameter of coaxial signal cables that comprise the probe cable. The thinner super-fine coaxial cable which is offering superior electronic and mechanical properties, such as 75 %IACS(International Annealed Copper Standard, electrical conductivity) and 700 ~ 800 MPa in tensile strength has to be developed. Cu-Ag based system is one of the most promising systems for high strength and high conductivity Cu alloys. In order to find the optimum conditions to obtain Cu-Ag-Zr-Co alloy with high strength and high electrical conductivity, the aging characteristics including work hardening of micro-Vickers hardness, tensile strength and electrical conductivity of this alloy were systematically measured at room temperature. Also the influence of aging treatment was investigated by transmission electron microscopy(TEM) and scanning electron microscopy(SEM) in this study. The aging treatment for precipitation was divided into two steps and carried out at various time and at different temperature and the multi-step aging treatment coupled with cold rolling was proposed for realizing Cu-Ag-Zr-Co alloys with high strength and high electrical conductivity. The electrical conductivity was improved from 31 %IACS to 91 %IACS remarkably and the tensile strength was increased from 230Mpa to 690Mpa greatly by an optimization of alloy composition and manufacturing process including aging.

Abstract: The solvent-based exfoliation of graphite, including into graphene and/or graphene-like platelets, is an important challenge. Here, we report a “direct” Friedel-Crafts acylation reaction between graphite and 4-ethylbenzoic acid (EBA) to afford edge-functionalized graphite (EFG). Unlike, for example, graphite oxide (GO), the functionalization is at the edges of the graphite and thus, the basal plane of individual layers in EFG is not functionalized. The EFG can be easily dispersed and exfoliated in common organic solvents to concentrations as high as 0.8 mg/mL. Large-are uniform films can be produced by solution-casting such dispersions on substrates and conductivities as high as 125 S/cm can be obtained by subsequent heat treatment at 900 °C under argon atmosphere. Hence, a few layers graphene obtained from annealing under argon atmosphere show the potential to replace Indium tin oxide (ITO).

Abstract: The development trend for diagnostics is reducing the diameter of coaxial signal cables that comprise the probe cable. The thinner super-fine coaxial cable which is offering superior electronic and mechanical properties, such as 75% IACS (International Annealed Copper Standard, electrical conductivity) and 700 ~ 800 MPa in tensile strength has to be developed. Three binary systems, Cu-Ag, Cu-Zr and Ag-Zr were thermodynamically optimized in the present study. Integration of optimized binary phase diagram can give useful information to predict the possible phases for the ternary Cu-Ag-Zr during manufacturing process. The large Cu5Zr particles were found at grain boundaries of as-cast alloys, which results from the strong affinity between Cu and Zr as well as no solubility of Zr in the Cu matrix. This coarse Cu5Zr phase was not dissolved fully during homogenization resides within the microstructure. Therefore, this phase induces decreasing in tensile strength after ageing.

Abstract: Boron-doped nanocrystalline silicon film was prepared through plasma enhanced chemical vapor deposition (PECVD) on silicon substrate and glass substrate under the high deposition pressure (332.5-399Pa) and the high deposition temperature (320-360°C). The film was investigated by Raman, electron probe microanalyser, conductivity and mobility experimenting techniques. The conductivity of the boron-doped nanocrystalline silicon film was 2.97×102Ω-1cm-1. The results showed that the interface between the film and the silicon substrate might have quantum spot and small size effect, causing the increasing of conductivity.