KONDO RESISTIVITY IN COPPER-CHROMIUM AT 35 GHZ

1978 ◽  
Vol 39 (C6) ◽  
pp. C6-848-C6-849
Author(s):  
M. D. Daybell ◽  
J. Meyer
Keyword(s):  
Copper Chromium

scholarly journals Comparison of Conventional and Flash Spark Plasma Sintering of Cu–Cr Pseudo-Alloys: Kinetics, Structure, Properties

Metals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 141
Author(s):  
Kirill V. Kuskov ◽  
Mohammad Abedi ◽  
Dmitry O. Moskovskikh ◽  
Illia Serhiienko ◽  
Alexander S. Mukasyan
Keyword(s):  
Heating Rate ◽  
Spark Plasma Sintering ◽  
Electric Circuits ◽  
Nanostructured Particles ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
The Media ◽  
Copper Chromium ◽  
Kinetics Of ◽  
Structure Properties

Spark plasma sintering (SPS) is widely used for the consolidation of different materials. Copper-based pseudo alloys have found a variety of applications including as electrodes in vacuum interrupters of high-voltage electric circuits. How does the kinetics of SPS consolidation for such alloys depend on the heating rate? Do SPS kinetics depend on the microstructure of the media to be sintered? These questions were addressed by the investigation of SPS kinetics in the heating rate range of 0.1 to 50 K/s. The latter conditions were achieved through flash spark plasma sintering (FSPS). We also compared the sintering kinetics for the conventional copper–chromium mixture and for the mechanically induced copper/chromium nanostructured particles. It was shown that, under FSPS conditions, the observed maximum consolidation rates were 20–30 times higher than that for conventional SPS with a heating rate of 100 K/min. Under the investigated conditions, the sintering rate for mechanically induced composite Cu/Cr particles was 2–4 times higher compared to the conventional Cu + Cr mixtures. The apparent sintering activation energy for the Cu/Cr powder was twice less than that for Cu–Cr mixture. It was concluded that the FSPS of nanostructured powders is an efficient approach for the fabrication of pseudo-alloys.

Fast microwave-assisted preparation of nickel–copper–chromium-layered double hydroxide as an excellent electrocatalyst for water oxidation

2021 ◽  
Author(s):  
Kamellia Nejati ◽  
Leila Jafari Foruzin ◽  
Zolfaghar Rezvani
Keyword(s):  
Charge Transfer ◽  
Layered Double Hydroxide ◽  
Water Oxidation ◽  
Bandgap Energy ◽  
Microwave Method ◽  
Optimal Amount ◽  
Microwave Assisted ◽  
Nickel Copper ◽  
Copper Chromium ◽  
Double Hydroxide

A well-designed NiCuCr-LDH was prepared using a simple microwave method. According to the OER results, doping optimal amount of Cu2+ into NiCr-LDH displayed superior OER activity, due to decreased bandgap energy and improved charge transfer.

Leachate Minimization by Reverse Osmosis

1992 ◽  
Vol 25 (3) ◽  
pp. 117-120 ◽  
Author(s):  
T. Bilstad ◽  
M. V. Madland
Keyword(s):  
Reverse Osmosis ◽  
Suspended Solids ◽  
Membrane Separation ◽  
Water Phase ◽  
Major Portion ◽  
Tubular Type ◽  
Iron Copper ◽  
Copper Chromium ◽  
Direct Discharge

Leachates from chemical and domestic landfills are defined as hazardous wastewater. Quantitative and qualitative control of leachate can be performed by membrane separation of the total produced leachate volume. Dissolved and suspended solids in the leachate are removed from the major portion of the water phase and either returned to the landfill or further treated. The particle - free permeate meets the effluent requirements for direct discharge to virtually any watercourse. An untreated leachate flow is concentrated thirteen times by tubular type reverse osmosis. The separation efficiencies are 99% for iron, copper, chromium and zinc. For suspended solids the removal is 100%.

Comparison of material transfer in electrical discharge machining of AISI H13 die steel

2009 ◽  
Vol 223 (7) ◽  
pp. 1733-1740 ◽  
Author(s):  
S Kumar ◽  
R Singh ◽  
T P Singh ◽  
B L Sethi
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Tungsten Powder ◽  
Material Transfer ◽  
Die Steel ◽  
Cent Increase ◽  
Aisi H13 ◽  
Copper Chromium ◽  
H13 Die Steel ◽  
And Tungsten

The electrical discharge machining (EDM) process is extensively used in the tool and die making industry for accurate machining of internal profiles in hardened materials. Although it is essentially a material removal process, efforts have been made in the recent past to use it as surface treatment method. This article investigates and compares the effect of material transfer from electrode bodies (copper, copper—chromium, and copper—tungsten) and tungsten powder suspended in the dielectric medium during die-sinking EDM of AISI H13 die steel. Results show a 76 per cent increase in micro-hardness by machining with a copper—tungsten electrode and a 111 per cent increase by machining with tungsten powder mixed in the dielectric. The copper—chromium electrode gives the best surface roughness (Ra) value of 2.67 μ m. Scanning electron microscopy and X-ray diffraction analysis of the machined surfaces show alloying of parent material with tungsten and tungsten carbide. Chemical composition of the machined surfaces was further checked on an optical emission spectrometer to verify the results. Besides a significant presence of tungsten, an increase in the percentage of carbon is also observed.

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