Effect of Pre-Aging on Properties of CuCrSn Alloy during Rolling and Aging

2021 ◽  
Vol 904 ◽  
pp. 76-81
Author(s):  
Jia Zhi Li ◽  
Hua Ding ◽  
Wei Lin Gao
Keyword(s):  
Electrical Conductivity ◽  
Dislocation Density ◽  
Cold Rolling ◽  
Aging Time ◽  
Room Temperature ◽  
Aging Treatment ◽  
Room Temperature Rolling

The effect of pre-aging on properties of Cu0.24Cr0.20Sn alloy before rolling and aging was studied in details. The results displayed the pre-aging was useful to improve the microhardness and conductivity of Cu0.24Cr0.20Sn alloy before cold rolling and aging, and the effect increased with the extension of pre-aging time. The microhardness and electrical conductivity of Cu0.24Cr0.20Sn alloy by first pre-aging at 400 °C for 2 h, second 85% rolling and then aging at 300 °C for 1 h can reach 189 HV and 85.4 %IACS, respectively. The TEM results indicated the density of precipitates increased with the increase of pre-aging time, and the interaction between precipitates and dislocations was gradually strengthened in the subsequent room-temperature rolling. The increase caused by pre-aging treatment before rolling and aging was mainly due to dislocation density strengthening.

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

2014 ◽  
Vol 783-786 ◽  
pp. 2468-2473 ◽  
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.

scholarly journals Effects of Cold Rolling and Aging Treatment on the Properties of Cu-Be Alloy

2019 ◽  
Vol 9 (4) ◽  
pp. 4500-4503
Author(s):  
M. I. Mohamed
Keyword(s):  
Cold Rolling ◽  
Aging Time ◽  
Aging Treatment ◽  
Exothermic Peak ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Cold Rolling Reduction ◽  
Cold Rolled ◽  
Precipitated Phases ◽  
Dsc Curves

The effects of precipitated phases during aging treatment on the properties of the Cu-Be alloy have been extensively studied. In this study, the effect of cold rolling on the precipitated phases of the Cu-Be alloy compared with non-deformed alloy during isothermal and low heating rate aging of 20C/min have been investigated. Hardness changes, differential scanning calorimetry (DSC), dilatation analysis, and transmission electron microscopy (TEM) were used in this study. Hardening and contraction were strongly increased at an early aging time for the cold rolled Cu-Be alloy. In addition, the DSC curves revealed an exothermic peak from the γ΄΄ phase. This peak increased and shifted to lower aging time by increasing the cold rolling reduction. In addition, the hardness remarkably increased at lower aging temperatures for the cold rolled specimens. The contraction from the dilatation curves and the exothermic peaks shifted to lower aging temperatures in cold rolled specimens. The hardening of Cu-Be alloy is believed to be from the γ΄ phase, and the contraction and the first exothermic peak in DSC curves from γ΄΄ phase. TEM observations are in a good agreement with the above explanation and strongly revealed that γ΄΄ and γ΄ phases were highly accelerated by the effect of cold rolling

Effect of heat treatment on microstructure and corrosion resistance of extruded ZK80 Mg alloy

2019 ◽  
Vol 9 (9) ◽  
pp. 1092-1099
Author(s):  
Fenghong Cao ◽  
Chang Chen ◽  
Zhenyu Wang
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Aging Time ◽  
Room Temperature ◽  
Aging Treatment ◽  
Corrosion Process ◽  
Corrosion Mechanism ◽  
Nacl Solution ◽  
Corrosion Properties

The corrosion characteristics and corrosion mechanism of the extruded ZK80 alloy with different states soaking in 3.5% NaCl solution at room temperature were analyzed via OM, SEM, EDS, XRD and static weightlessness method and other experimental analysis methods. The results show that when the aging temperature is constant, and the corrosion rate decreases with the lengthen of aging time, while when the corrosion time is constant, the corrosion rate increases with the increase in aging time. Appropriate aging treatment not only refines the grain of the alloy, but also precipitates the Mg–Zn phase which can effectively prevent the corrosion process and improve the anti-corrosion properties of the alloy. The main corrosion characteristics of the alloy are filamentary corrosion and pitting corrosion.

Characterization of aging behavior of precipitates and dislocations in copper-based alloys

2010 ◽  
Vol 25 (2) ◽  
pp. 104-107
Author(s):  
Shigeo Sato ◽  
Yohei Takahashi ◽  
Kazuaki Wagatsuma ◽  
Shigeru Suzuki
Keyword(s):  
Dislocation Density ◽  
Aging Time ◽  
Line Profile ◽  
Small Angle ◽  
Profile Analysis ◽  
Aging Treatment ◽  
Scattering Method ◽  
Line Profile Analysis ◽  
X Ray ◽  
X Ray Scattering

The growth of precipitates in a deformed Cu–Ni–Si alloy with an aging treatment and the rearrangement of dislocations were investigated using small-angle X-ray scattering method and XRD line-profile analysis. The small-angle X-ray scattering method was used for characterizing the growth behavior of the precipitates. The results showed that the precipitates grew gradually to a few nanometers in radius when aged under the condition that the alloy exhibited a maximum of the hardness due to precipitation hardening. The growth rate rose from the onset of the overaging, where the hardness started to decrease. The line-profile analysis of copper-based alloy diffraction peaks using modified Williamson–Hall and modified Warren–Averbach procedures yielded a variation in the dislocation densities of the alloy as a function of the aging time. The dislocation density of the alloy before the aging treatment was estimated to be 1.7×1015 m−2 and its high value was held up to the peak-aging time. With the onset of the overaging, however, the dislocation density distinctly decreased by about 1 order of magnitude indicating that a large amount of the dislocations rearranged to release the alloy from the high dislocation-density state. The results suggest that the massive rearrangement of dislocations was accompanied with coarsening of the precipitates.

Microstructure Evolution in Bulk Nanostructured Copper during Repeated Cold Rolling

2012 ◽  
Vol 248 ◽  
pp. 43-47
Author(s):  
Lei Liu ◽  
Han Zhuo Zhang ◽  
Qin Lan Zhao
Keyword(s):  
Grain Size ◽  
Cold Rolling ◽  
Grain Growth ◽  
Microstructure Evolution ◽  
Room Temperature ◽  
Maximum Value ◽  
Deformation Stages ◽  
Average Grain Size ◽  
Dislocation Interactions ◽  
Room Temperature Rolling

Room temperature rolling tests were performed on a bulk nanostructured Cu with an average grain size of 90 nm. The results indicated a high thickness reduction ( ) of 92% without crack and an increased {220} texture as the rolling processes continued. Microstructure evolution of the deformed nanostructured Cu could be characterized by several deformation stages. Grain growth and coalescence was prevalent in the early deformation stage, while grain boundaries were impaired and replaced by dislocation interactions when 24%. Microhardness of the deformed nanostructured Cu increased sharply to a maximum value of 1.61 GPa at 8% and then slightly decreased to 1.58 GPa at 92%.

Optimization of strength, ductility and electrical conductivity of a Cu–Cr–Zr alloy by cold rolling and aging treatment

Vacuum ◽  
2019 ◽  
Vol 167 ◽  
pp. 329-335 ◽  
Author(s):  
Ao Meng ◽  
Jinfeng Nie ◽  
Kang Wei ◽  
Huijun Kang ◽  
Zhuangjia Liu ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Cold Rolling ◽  
Aging Treatment ◽  
Zr Alloy

Cold-Rolling and Subsequent Annealing of Ti-Rich Tial Polysynthetically Twinned (PST) Crystals

1990 ◽  
Vol 213 ◽  
Author(s):  
M.H. Oh ◽  
H. Inui ◽  
S.R. Nishitani ◽  
M. Yamaguchi
Keyword(s):  
Dislocation Density ◽  
Cold Rolling ◽  
Shear Deformation ◽  
Lamellar Structure ◽  
Room Temperature ◽  
Subsequent Annealing ◽  
Second Stage ◽  
Cold Rolled ◽  
Two Stages ◽  
Equiaxed Grains

ABSTRACTPolysynthetically twinned (PST) crystals of Ti-rich TiAl have been grown and specimens cut from these crystals have been rolled at room temperature and subsequently annealed at 900°C and 1000°C. When the shear deformation parallel to the lamellar boundaries occurs during rolling, PST crystals of Ti-rich TiAl can be rolled to about 50% reduction in thickness at room temperature.The recovery in microhardness occurs in two stages; the first stage associated with the decrease in dislocation density and the second stage connected with the annealing-out of deformation induced twins. The recrystallization mode depends on the amount of reduction. Up to 20% reduction, the lamellar structure is preserved even after the full recovery in hardness. When the amount of reduction exceeds 40%, a structure composed of equiaxed grains of TiAl is obtained after recrystallization. A mechanism of recrystallization of cold-rolled PST crystals, which may explain the dependence of recrystallization mode on the amount of reduction, is proposed.

scholarly journals EFFECT OF AGING TREATMENT PARAMETERS ON MICROSTRUCTURE AND PROPERTIES OF Cu-Ni-Si ALLOY

2018 ◽  
Vol 54 (5A) ◽  
pp. 75
Author(s):  
Phung Tuan Anh
Keyword(s):  
Electrical Conductivity ◽  
Aging Time ◽  
Cold Deformation ◽  
Aging Treatment ◽  
Maximum Hardness ◽  
Deformation Degree ◽  
Subsequent Aging ◽  
Microstructure And Properties ◽  
Alloy Increase

In this paper, effect of cold pre-deformation and sequent aging time and temperature on microstructure and properties of Cu-2.8Ni-1.0Si alloy are reported. The results shown that, hardness and electrical conductivity of alloy increase with increasing cold deformation degree after quenching and subsequent aging. With undeformed specimens after quenching, hardness and electrical conductivity of alloy reach maximum values with subsequent aging at 425 and 475 oC, respectively. Alloy attains maximum hardness of 255 HV5 with aging at 425 oC for 4.5 hours, while maximum electrical conductivity of 38.5 %IACS with aging at 475 oC for 8 hours. In the case of deformed specimens after quenching and subsequent aging, this rule is still preserved. Especially, at 70 % cold pre-deformation degree, alloy attains the maximum hardness of 274.3 HV5 with aging at 425 oC for 3.5 h, while maximum electrical conductivity reaches 42.4 % IACS with aging at 475 oC for 6 h.

Effect of Cold Rolling Deformation on Aging Precipitation of Cu-Cr-Sn-Zn Alloy

2009 ◽  
Vol 79-82 ◽  
pp. 1507-1510 ◽  
Author(s):  
Juan Hua Su ◽  
Shu Guo Jia ◽  
Feng Zhang Ren ◽  
Ping Liu ◽  
Bao Hong Tian
Keyword(s):  
Electrical Conductivity ◽  
Cold Rolling ◽  
Precipitation Hardening ◽  
Aging Treatment ◽  
Nucleation Site ◽  
Transmission Electron ◽  
Aging Precipitation ◽  
Aging Properties ◽  
Rolling Deformation ◽  
Zn Alloy

The effects of different extent of cold rolling on the aging properties in Cu-Cr-Sn-Zn alloy are investigated by hardness and electrical conductivity analysis and microstructure TME (transmission electron microscopy) observation of the alloy. The results shows that dislocations provide nucleation site for precipitation during aging treatment, and result in the precipitation hardening effect from a finer size of precipitates. At 60% ratio of cold rolling and aged at 450°Cfor 1h, the hardness and electrical conductivity can reach 171.3HV and 71.5%IACS respectively.

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