Microstructure and Properties of Cu-Cr Alloys Prepared by a Shortened Process and a Conventional Process

The microstructure and properties of Cu-0.4wt%Cr alloys prepared by a shortened process and a conventional process were investigated by means of optical microscopy (OM), transmission electron microscopy (TEM), hardness testing and electrical conductivity measurement. After online hot rolling- quenching and cold rolling with 60% reduction and then aging at 450°C for 30min (process A), and solution treatment - cold rolling with 60% reduction - aging 450°C for 60min (process B), good properties combination of the alloys are obtained, and the hardness and electrical conductivity reach to 156HV, 86.4%IACS and 169HV, 81.1%IACS, respectively, and the shortened process (A) is suitable for commercial copper strip production. Plenty of fine and dispersed precipitates are responsible for the hardness and electrical conductivity improvement of the alloys. The difference of properties between process A and B is resulting form the difference of effective precipitates volume fraction under the various processes.

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Influence of Co on Strength of Cu-Ni-Co-Si Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.2468 ◽

2014 ◽

Vol 783-786 ◽

pp. 2468-2473 ◽

Cited By ~ 8

Author(s):

Atsushi Ozawa ◽

Chihiro Watanabe ◽

Ryoichi Monzen

Keyword(s):

Electrical Conductivity ◽

Dislocation Density ◽

Cold Rolling ◽

Volume Fraction ◽

Crystal System ◽

The Difference ◽

Co Alloys

The effects of Co on the strength of Cu-Ni-Co-Si alloys have been investigated using Cu-2.0wt%Ni-0.5wt%Si (0%Co), Cu-1.4wt%Ni-0.6wt%Co-0.5wt%Si (0.6%Co) and Cu-1.0wt% Ni-1.0wt%Co-0.5wt%Si (1.0%Co) alloys produced by combining cold rolling to a 25% reduction with aging. Aging the 0.6%Co and 1.0%Co alloys at 525 and 425°C produces orthorhombic (Ni, Co)2Si precipitates that have the same crystal system as Ni2Si precipitates formed in the 0%Co alloy. The larger the amount of Co in the three alloys is, the higher the strength and electrical conductivity of the alloys initially aged at 525°C, rolled to a 25% reduction and re-aged at 425°C become. The increase in strength with increasing Co content is caused by both of the decrease in inter-precipitate spacing and increase in dislocation density. The increase in strength by re-aging at 425°C becomes more pronounced as the Co content increases. This arises because the larger the amount of Co is, the larger the difference between the equilibrium solubilities at 525 and 425°C becomes, the more the volume fraction of precipitates is increased by re-aging at 425°C.

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Annealing effect of micro-alloying on the microstructure and properties of Cu-10Zn alloy

E3S Web of Conferences ◽

10.1051/e3sconf/201913601015 ◽

2019 ◽

Vol 136 ◽

pp. 01015

Author(s):

Wei Chen ◽

Jiarui Hu ◽

Yi Xie ◽

Hengyi Zhou ◽

Chao Feng ◽

...

Keyword(s):

Electrical Conductivity ◽

Aging Process ◽

Conductivity Measurement ◽

Hardness Test ◽

Precipitation Strengthening ◽

Strengthening Effect ◽

Electrical Conductivity Measurement ◽

Microstructure And Properties ◽

Transmission Electron ◽

The Matrix

The effect of Fe and P (Ni and Si) on the microstructure and properties of Cu-10Zn alloys has been investigated using hardness test, electrical conductivity measurement, optical microscopy and transmission electron microscopy. γ-Fe precipitates formed during the aging process, but there is almost no effect of precipitation strengthening on the Cu-Zn-Fe-P alloy and sparsely Fe3P precipitates existed in the matrix. After homogenization treatment at 900°C for 2h, hot rolling by 80%, cold rolling by 80%, and ageing treatment at 400°C for 30min, Cu-Zn-Ni-Si alloy obtained good combinations of hardness (219.8HV) and electrical conductivity(28.2%IACS). Ni2Si precipitates formed during aging process and the crystal orientation relationship between matrix and precipitates is:(200)α || (100)δ, [100]α || [010]δ,. Compared with Cu-Zn-Fe-P, Cu-Zn-Ni-Si has finer grains, and the precipitation strengthening effect is more obvious.

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Electrical Conductivity Measurement on Metallic Materials With a Cylindrical Resonator

IEEE Transactions on Electromagnetic Compatibility ◽

10.1109/temc.2021.3070082 ◽

2021 ◽

pp. 1-9

Author(s):

Yunfeng Dong ◽

Morten Stendahl Jellesen ◽

Rune Juul Christiansen ◽

Jesper Hovelskov ◽

Jorgen Sundgren ◽

...

Keyword(s):

Electrical Conductivity ◽

Conductivity Measurement ◽

Metallic Materials ◽

Electrical Conductivity Measurement ◽

Cylindrical Resonator

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Electrical Properties of Y0.06Sr0.94Ti0.6Fe0.4O3-δ-YSZ Composites as Electrode Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.697.327 ◽

2016 ◽

Vol 697 ◽

pp. 327-330 ◽

Cited By ~ 1

Author(s):

Ke Shan ◽

Xing Min Guo ◽

Feng Rui Zhai ◽

Zhong Zhou Yi

Keyword(s):

Electrical Conductivity ◽

Electrode Materials ◽

Electronic Conductivity ◽

Ionic Conductivities ◽

Conductivity Measurement ◽

Transference Numbers ◽

Secondary Phases ◽

Electrical Conductivity Measurement ◽

Total Electrical Conductivity ◽

Phase Compatibility

Y0.06Sr0.94Ti0.6Fe0.4O3-δ-YSZ composites were prepared by mixing Y, Fe co-doped SrTiO3 (Y0.06Sr0.94Ti0.6Fe0.4O3-δ known as YSTF) and 8 mol% Y2O3 stabilized ZrO2 (YSZ) in different weight fractions. The phase stability, phase compatibility, microstructure and mixed ionic-electronic conductivity of composites were investigated. Phase analysis by XRD showed no clearly detectable secondary phases. The electrical conductivity measurement on the YSTF-YSZ composites showed a drastic decrease in total electrical and ionic conductivities when more than 10 wt% of YSZ was used in the composites. The total electrical conductivity was 0.102 S/cm for Y0.06Sr0.94Ti0.6Fe0.4O3-δ and 0.043 S/cm for YSTF-20YSZ at 700 oC, respectively. The value at 700 oC is approximately 2.4 times higher than that of YSTF-20YSZ. The ionic conductivity of Y0.06Sr0.94Ti0.8Fe0.2O3-δ varies from 0.015S/cm at 700 oC to 0.02 S/cm at 800 oC, respectively. The value at 800°C is approximately 12.5 times higher than YSTF-20YSZ. The ion transference numbers of YSTF-YSZ composites vary from 0.14 to 0.28 at 800 °C.

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