Microstructure and Properties of Cu-3.2Ni-0.75Si-0.3Zn Alloy for Lead Frame

2007 ◽  
Vol 26-28 ◽  
pp. 569-572 ◽  
Author(s):  
Yi Zhang ◽  
Ping Liu ◽  
Bao Hong Tian ◽  
D.M. Zhao ◽  
Shu Guo Jia ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Age Hardening ◽  
Lead Frame ◽  
Transformation Kinetics ◽  
Transmission Electron ◽  
Resistance Variation ◽  
Electrical Resistance Variation ◽  
Means Of Transmission

The effect of aging temperature and aging time on properties of Cu-3.2Ni-0.75Si-0.3Zn alloy were studied. The alloys were isochronally or isothermally aged after solution treatment. The cold rolling prior to the aging treatment was used to increase the precipitation rate .The microstructure of the alloy was studied by means of transmission electron microscope (TEM). The results show that the fine and dispersed precipitates are fully coherent with the Cu matrix and make the alloy possesses higher hardness and conductivity after the alloy was solution at 1173K and then aged at different time. The precipitates responsible for the age-hardening effect was Ni2Si.The transformation kinetics were studied by analyzing the electrical resistance variation of the solution Cu-3.2Ni-0.75Si-0.3Zn alloy in the process of aging.

Age-Hardening Characteristics of Cu-3Ag-0.5Zr Alloy

2012 ◽  
Vol 710 ◽  
pp. 563-568 ◽  
Author(s):  
S. Chenna Krishna ◽  
K. Thomas Tharian ◽  
Bhanu Pant ◽  
Ravi S. Kottada
Keyword(s):  
Electrical Conductivity ◽  
Rocket Engine ◽  
Copper Alloys ◽  
Solution Treatment ◽  
Aging Treatment ◽  
High Strength ◽  
Average Diameter ◽  
Age Hardening ◽  
Liquid Rocket

Among the copper alloys, the Cu-3Ag-0.5Zr alloy is one of the potential candidates for combustion chamber of liquid rocket engine because of its optimum combination of high strength with thermal conductivity. The present study is a detailed characterization of microstructure, strength, and electrical conductivity during the aging treatment. The aging cycle for Cu-3Ag-0.5Zr alloy after the solution treatment (ST) was optimized to obtain higher hardness without compromising on electrical conductivity. The precipitates responsible for strengthening in aged samples are identified as nanocrystalline Ag precipitates with an average diameter of 9.0±2.0 nm.

Microstructure and Aging Behavior in AM60 Magnesium Alloy Cast into Sand and Permanent Molds

2010 ◽  
Vol 654-656 ◽  
pp. 679-682 ◽  
Author(s):  
Hiroshi Yamada ◽  
Mitsuaki Furui ◽  
Susumu Ikeno ◽  
Yukio Sanpei ◽  
Katsuya Sakakibara ◽  
...  
Keyword(s):  
Magnesium Alloy ◽  
Aging Temperature ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Age Hardening ◽  
Cellular Precipitation ◽  
Lower Aging Temperature ◽  
Peak Aging ◽  
Alloy Castings ◽  
Hardening Curve

AM60 magnesium alloy castings gave the solution treatment at 688K for 86.4ks. After that, aging treatment was carried out at three temperatures of 473, 498 and 523K. The age hardening curve obtained, hardness of all the specimens in the condition of peak aging was increased by decreasing the aging temperature. In the condition of long aging time, a cellular precipitation grows up from grain boundary to crystal grain. Fine cellular precipitation and intergranular precipitation obviously occurs at the lower aging temperature.

TEM Study for Strengthening Mechanisms in Elgiloy

2010 ◽  
Vol 442 ◽  
pp. 268-274 ◽  
Author(s):  
I.N. Qureshi ◽  
S. Rani ◽  
F. Yasmin ◽  
M. Farooque
Keyword(s):  
Electron Microscope ◽  
Cold Work ◽  
Cold Deformation ◽  
Solution Treatment ◽  
Optical Microscope ◽  
Age Hardening ◽  
Solution Treated ◽  
Transmission Electron ◽  
P Transformation ◽  
Cold Worked

Elgiloy is Co based alloy (40wt%Co, 20wt%Cr, 15wt%Ni, 14wt%Fe and 7wt%Mo). It was strengthened by cold work and is capable of additional hardening by aging. The effects of solution treatment, cold working and age-hardening on the microstructure of elgiloy were investigated using optical microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). As rolled strips were solution treated at 1065°C/1hr. These solution treated strips were then reduced 50% by cold rolling. After cold-deformation both є-hcp phase and fcc deformation twins are also considered to coexist at room temperature. The cold worked strips were then age hardened at (450-600)°C. The age hardened strips showed formation of additional є-phase (via α f c c є h c p transformation).

scholarly journals Electrical Resistance Variation of MWCNT/PMMA Composite for Gaseous Toluene Detection

2009 ◽  
Vol 42 (Supplement.) ◽  
pp. s238-s241 ◽  
Author(s):  
Amornwong Srisurichan ◽  
Adi Ilcham ◽  
Apinan Soottitantawat ◽  
Yongyuth Wanna ◽  
Noriaki Sano ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Resistance Variation ◽  
Electrical Resistance Variation ◽  
Gaseous Toluene

Aging Behavior of Al-Li-Cu-Mg Alloy Processed by High-Pressure Torsion

2010 ◽  
Vol 654-656 ◽  
pp. 1243-1246 ◽  
Author(s):  
Seung Won Lee ◽  
Daichi Akama ◽  
Z. Horita ◽  
Tetsuya Masuda ◽  
Shoichi Hirosawa ◽  
...  
Keyword(s):  
High Pressure ◽  
High Pressure Torsion ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Rolling Process ◽  
Mg Alloy ◽  
Age Hardening ◽  
Subsequent Aging ◽  
Solid Solution Treatment ◽  
Conventional Rolling

This study presents an application of high-pressure torsion (HPT) to an Al-Li-Cu-Mg alloy (2091). The alloy was subjected to solid solution treatment at 505oC for 30 minutes and was processed by HPT under 6 GPa for 5 revolutions at room temperature. The hardness increased with straining and saturated to a constant level at 225 Hv. Aging was undertaken on the HPT-processed alloy at 100, 150 and 190oC for the total periods up to 9.3 days. The aging treatment led to a further increase in the hardness to ~275 Hv. It is shown that the simultaneous strengthening of the alloy due to grain refinement and age hardening was successfully achieved by application of HPT and subsequent aging treatment. The enhancement of the strength is prominent when compared with the application of a conventional rolling process.

The Age-Hardening Mechanism of Nanocrystalline Ni-P Alloys Synthesized by Electrodeposition

2014 ◽  
Vol 922 ◽  
pp. 338-343
Author(s):  
Yosuke Kasazaki ◽  
Hiroyuki Miyamoto ◽  
Hiroshi Fujiwara
Keyword(s):  
Grain Size ◽  
Aging Treatment ◽  
Strengthening Mechanism ◽  
Age Hardening ◽  
Dislocation Slip ◽  
Subsequent Aging ◽  
Hardening Mechanism ◽  
Transmission Electron ◽  
Average Grain Size ◽  
Nanocrystalline Structures

Strengthening mechanism of age-hardenable electrodeposited Ni-P alloy was investigated focusing on the role of Ni3P precipitates in nanocrystalline structures. Specimens were synthesized by electrodeposition followed by aging treatment at temperatures raging from 473 to 773 K. As-electrodeposited structures became only Ni phase and Ni3P precipitated by the subsequent aging treatment. Distribution of grain size of Ni matrix was examined in detail by field-emission type transmission electron microscopy. The specimens became harder with higher P content after the electrodeposion and aging treatment. After the aging treatment 573 K or bellow, average grain size of Ni matrix was under 10 nm. On the other hand, after aging at 673 and 773 K both the grain size of Ni matrix and Ni3P particle size grow to be comparable. It is considered the hard interphase boundary to the dislocation slip is responsible to the hardening rather than the classical precipitation hardening.

Analyzing Si Precipitation on Age Hardening of an Al-Si-Mg Cast Alloy

2010 ◽  
Vol 146-147 ◽  
pp. 1685-1689
Author(s):  
Gui Qing Wang ◽  
Yan Liu ◽  
Guo Cheng Ren ◽  
Zhong Kui Zhao
Keyword(s):  
Cast Alloy ◽  
Solution Treatment ◽  
Hardness Measurement ◽  
Mg Alloy ◽  
Age Hardening ◽  
Micro Hardness ◽  
Tem Analysis ◽  
Cast Sample ◽  
Transmission Electron ◽  
Cast Condition

The correlation of age hardening behavior and Si precipitation in α(Al) of Al-8wt%Si-0.35wt%Mg alloy has been investigated by micro hardness measurement, electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) analysis. The EPMA results show that Si concentration in the center of α (Al) dendrites is higher than that in the edge and the main concentration is about 1.5wt% for Al-8wt%Si-0.35wt%Mg alloy in as cast condition. After solution treatment at 530 °C for 8 h followed by water quenching (T4 treatment), hardness value decreases 9 HV, which is accompanied by the decrease of Si concentration in α (Al). Aging the as-cast sample and T4 treatment sample at 150 °C for 20 h, the main concentration of Mg and Si in α (Al) changes little. Hardness value after as-cast aging is only 3 HV lower than that after T6 treatment. Nanometer Si particles and β″ and/or β′ phases are found in aged samples. The higher hardness value for as-cast aging samples should contribute to the nanometer Si particles in α (Al).

Effect of Aging Temperature on Microstructure and Properties of V Alloyed High Manganese Austenitic Steel

2017 ◽  
Vol 898 ◽  
pp. 766-771 ◽  
Author(s):  
Yi Fan Feng ◽  
Ren Bo Song ◽  
Shi Guang Peng ◽  
Chang Hong Cai ◽  
Zhi Dong Tan
Keyword(s):  
Electron Microscopy ◽  
Aging Temperature ◽  
Energy Dispersive Spectrometer ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Austenitic Steels ◽  
Striking Difference ◽  
X Ray Diffraction ◽  
High Manganese ◽  
Transmission Electron

The effect of aging temperature on microstructure and mechanical properties of Fe-16Mn-1.3C-0.3V steel was investigated. After a series of heat treatment experimental processes, including solution treatment at 1080 oC for 1 h then aging treatment at 350 oC, 400 oC, 450 oC, 500 oC and 550 oC for 1 h respectively, the microstructure of V alloyed high manganese austenitic steels were studied using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experimental steel had the best comprehensive performance after aging treated at 450 oC for 1 h. It presented hardness of 249HB, impact toughness of 215 J·cm-2, tensile strength of 707 MPa, yield strength of 421 MPa and elongation of 30.8%. With the aging temperature increased, the amount of precipitates increased and precipitates gradually transformed from globularity to needle. EDS analysis showed the most striking difference between two types carbides. That the globular carbide had a lot of vanadium element, which could cause the hardness of globular carbide higher than needle-like carbide. TEM showed the size of these globular carbide particles were 10~100 nm. SADP demonstrated that the fine globular precipitate was vanadium carbide (VC).

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