Micromechanism Study of Strengthening Effect of Copper on Gold Thiosulfate Leaching

The purpose of this research is to investigate the mechanical and corrosion characteristics of Ni-Cu alloyed Austempered Ductile Iron before and after austempering process. Specimens of ductile iron and 0.5% Cu-Ni ductile iron were produced through conventional CO2 sand casting method. The specimens were then austenitized at 9000C before austempered at 3500C at three different holding times which were 1 hour, 2 hours and 3 hours subsequently. The corrosion characteristics of newly developed material were obtained by means of polarization test and the mechanical testing involved tensile test (TS 138 EN1002-1), Rockwell hardness test and Charpy Impact test (ASTM E23). Density test as well as microstructure and SEM observations were also done to ductile iron and Cu-Ni alloyed ductile iron samples. All the testing was done to both as cast and austempered specimens. Addition of copper and Nickel was found to slightly increased the mechanical properties due to solid strengthening effect of Copper and Nickel. The results also indicated that austempering process at 1 hour gives the optimum mechanical properties in term of tensile strength and impact properties compared to other specimens. Increasing the austempering holding times to 2 hours and 3 hours, in contrast had resulted in decrement of the mechanical properties. There are however only slight improvement in hardness properties and no significant effect on density properties of the specimens.

Download Full-text

Influence of Thermo-Mechanical Processing on the Microstructure of Beryllia Dispersed Nickel Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071363 ◽

1973 ◽

Vol 31 ◽

pp. 184-185

Author(s):

M.S. Grewal ◽

S.A. Sastri ◽

N.J. Grant

Keyword(s):

High Temperature ◽

Nickel Alloys ◽

Thermomechanical Processing ◽

Cold Work ◽

High Temperature Strength ◽

Strengthening Effect ◽

Mechanical Processing ◽

Uniform Dispersion ◽

Oxide Particles ◽

Nickel Base

Currently there is a great interest in developing nickel base alloys with fine and uniform dispersion of stable oxide particles, for high temperature applications. It is well known that the high temperature strength and stability of an oxide dispersed alloy can be greatly improved by appropriate thermomechanical processing, but the mechanism of this strengthening effect is not well understood. This investigation was undertaken to study the dislocation substructures formed in beryllia dispersed nickel alloys as a function of cold work both with and without intermediate anneals. Two alloys, one Ni-lv/oBeo and other Ni-4.5Mo-30Co-2v/oBeo were investigated. The influence of the substructures produced by Thermo-Mechanical Processing (TMP) on the high temperature creep properties of these alloys was also evaluated.

Download Full-text

Effect of Improved ThO2 Particle Dispersion in Nickel on High-Temperature Strength

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069211 ◽

1970 ◽

Vol 28 ◽

pp. 444-445

Author(s):

E. R. Kimmel ◽

H. L. Anthony ◽

W. Scheithauer

Keyword(s):

High Temperature ◽

Metal Matrix ◽

Oxide Particle ◽

Oxide Phase ◽

Dislocation Motion ◽

Particle Dispersion ◽

High Temperature Strength ◽

Strengthening Effect ◽

Oxide Particles ◽

The Stability

The strengthening effect at high temperature produced by a dispersed oxide phase in a metal matrix is seemingly dependent on at least two major contributors: oxide particle size and spatial distribution, and stability of the worked microstructure. These two are strongly interrelated. The stability of the microstructure is produced by polygonization of the worked structure forming low angle cell boundaries which become anchored by the dispersed oxide particles. The effect of the particles on strength is therefore twofold, in that they stabilize the worked microstructure and also hinder dislocation motion during loading.

Download Full-text

Effect of Copper on Crude Rubber

Industrial & Engineering Chemistry ◽

10.1021/ie50095a743 ◽

1917 ◽

Vol 9 (12) ◽

pp. 1092-1093 ◽

Cited By ~ 1

Keyword(s):

Effect Of Copper

Download Full-text

The Effect of Copper Ions on Clot Lysis Time in the Fibrinolytic Assay of Streptokinase

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656246 ◽

1965 ◽

Vol 13 (02) ◽

pp. 477-483

Author(s):

Alwin B. Bogert

Keyword(s):

Copper Ions ◽

Borate Buffer ◽

Fibrinolytic System ◽

Clot Lysis ◽

Distilled Water ◽

Naturally Occurring ◽

Lysis Time ◽

Low Levels ◽

Effect Of Copper ◽

Clot Lysis Time

SummaryExperiments were conducted to determine why different lots of Borate Buffer reagent affect the clot lysis times obtained in the fibrinolytic assay of Streptokinase. Minerals naturally occurring in distilled water were screened individually to determine their influence on lysis. Copper was found to have a very pronounced effect in this regard on the fibrinolytic system in that low levels reduce the lysis time and high levels increase it.

Download Full-text

Effect of Copper Slag as a Fine Aggregate on the Durability Characteristics of High-Performance Concrete (HPC) Containing Silica Fume

Journal of Advanced Research in Civil and Environmental Engineering ◽

10.24321/2393.8307.202002 ◽

2020 ◽

Vol 07 (02) ◽

pp. 1-10

Author(s):

Rizwan Ahmad Khan ◽

Keyword(s):

Silica Fume ◽

High Performance ◽

High Performance Concrete ◽

Copper Slag ◽

Chloride Penetration ◽

Interfacial Transition Zone ◽

Fine Aggregate ◽

Fresh Properties ◽

Fine Aggregates ◽

Effect Of Copper

This paper investigates the fresh and durability properties of the high-performance concrete by replacing cement with 15% Silica fume and simultaneously replacing fine aggregates with 25%, 50%, 75% and 100% copper slag at w/b ratio of 0.23. Five mixes were analysed and compared with the standard concrete mix. Fresh properties show an increase in the slump with the increase in the quantity of copper slag to the mix. Sorptivity, chloride penetration, UPV and carbonation results were very encouraging at 50% copper slag replacement levels. Microstructure analysis of these mixes shows the emergence of C-S-H gel for nearly all mixes indicating densification of the interfacial transition zone of the concrete.

Download Full-text