Age-Hardening Characteristics of Cu-Ni-Si Alloy after Cold Deformation

2012 ◽  
Vol 217-219 ◽  
pp. 294-298 ◽  
Author(s):  
Xiang Peng Xiao ◽  
Bai Qing Xiong ◽  
Qiang Song Wang ◽  
Guo Liang Xie ◽  
Li Jun Peng
Keyword(s):  
Heat Treatment ◽  
Electrical Conductivity ◽  
Aging Time ◽  
Cold Deformation ◽  
Solution Treatment ◽  
The Other ◽  
Age Hardening ◽  
Precipitation Strengthening ◽  
Peak Hardness ◽  
Strengthening Mechanisms

The microstructural features and heat treatment response of Cu-2.1Ni-0.5Si-0.2Zr-0.05Cr (wt.%) alloy have been investigated. The alloy was aged at 400°C、450°C and 500°C after a cold deformation of 70% reduction. The variation in hardness and electrical conductivity of the alloy was measured as a function of aging time. The results indicated the highest peak hardness value of approximately 205HV for the alloy aged at 400°C for 4h after the solution treatment and cold deformation. The alloy has two main phases, one is Ni2Si phase, and the other is Cr2Zr phase. The strengthening mechanisms of the alloy include spinodal decomposition strengthening, ordering strengthening and precipitation strengthening.

scholarly journals Prior Solutionising Deformation Consequence on the Aging Characteristics of Steel Powder Reinforced Al 7075 Composites

2019 ◽  
Vol 8 (2S11) ◽  
pp. 2256-2261
Keyword(s):  
Aluminum Alloy ◽  
Strain Hardening ◽  
Cold Deformation ◽  
Solution Treatment ◽  
Steel Powder ◽  
Heat Treatments ◽  
Age Hardening ◽  
Peak Hardness ◽  
Alloy Matrix ◽  
Al 7075

Globally, in the application of structural materials, aluminum composites are emerging as pioneer materials due to balanced properties like ductility, strength, hardness and weight to volume ratio. It is obvious that addition of harder steel powder reinforcements to the softer aluminum alloy matrix will yield in larger benefits as energy efficient method, durability and recyclability for the composite. Infact, improvement in hardness levels at low temperatures in softer matrix aluminium alloys is the order of the day for wear related applications. Aluminum alloy composites especially Al 7075 matrix containing solid state soluble elements like copper, zinc and silicon with or without wetting agents like magnesium are heat treatable and got medium strength. The alloy matrix dispersed with solid reinforcements like carbides, oxides, flyash and steel powder contribute for the property improvement by tailoring the suitable heat treatment with flexibility in process parameters. Cold deformation assisted heat treatments, prior to or post solutionising challenge conventional heat treatments like age hardening or precipitation hardening. When the cold deformation is provided before solution treatment increases hardness by strain hardening with increased nucleation sites for phase transformation. When partial solutionising is given to the cold deformed composite retains the partial strain hardening effect on the specimen compared to complete solutionising. The retention of partial strain hardening followed by further aging develops complex interaction effect of strain hardening coupled with controlled precipitation of intermetallics on the composite for drastic uplift in hardness property. During conventional age hardening hardness and strength of the samples increase. Reduction in peak hardness value with increasing aging temperature is the renowned behaviour of age hardenable composites. The obtained peak hardness value is further increasing when cold deformation is supported with prior intentional deformation. Considering these features, it is proposed to perform prior solutionising deformation followed by subsequent aging on the stir cast Al 7075 –steel powder reinforced composite and analyse the microstructure and hardness distribution pattern by varying the steel powder quantity (0, 3 and 6 wt%), deformation density (10 and 20%) and aging temperatures (100 and 180oC)

Post Solutionising Rolling Sway on the Precipitation Behaviour of Eutectoid Steel Powder Reinforced Al7075 Ternary Alloy Composites

2020 ◽  
Vol 995 ◽  
pp. 9-14
Author(s):  
Rajesh Bhat ◽  
Sathyashankara Sharma ◽  
M.C. Gowrishankar ◽  
Manjunath Shettar ◽  
Pavan Hiremath ◽  
...  
Keyword(s):  
Ternary Alloy ◽  
Cold Deformation ◽  
Solution Treatment ◽  
Steel Powder ◽  
Age Hardening ◽  
Peak Hardness ◽  
Second Phase ◽  
Eutectoid Steel ◽  
Alloy Matrix ◽  
Mechanical Working

The solitary distinguished thermal treatment to aluminium alloy matrix of nonferrous group with uniformly dispersed reinforcement particles is precipitation or age hardening with or without mechanical working. Al7075 ternary alloy composites belongs to Al-Zn-Mg group and bulk properties can be enhanced by the formation of the immensely small consistently spread out precipitates of solute rich second phase within the matrix phase. The treatment comprises solutionising (550°C) supported by controlled aging (100 and 180°C) below the solvus temperature of the given alloy. Aging expedites the diffusion of solute atoms to form secondary particles (intermetallics) from the room temperature super saturated solid solution. This process is supported by deformation known as rolling as post activity, develops strain hardening in matrix and reinforcement. The present work shows the distinction in the aging phenomenon on alloy and alloy matrix composites (reinforced with 3 and 6 wt% of eutectoid steel powder, 10-30 micron size) upon undergoing cold rolling prior to aging i.e., after solution treatment. The variation in the hardness distribution with aging kinetics for both aging temperatures with and without cold deformation (10 and 20%) in between the consecutive stages like, solution treatment and aging were investigated and peak hardness values were noted in each aging temperatures and results were analysed. In every hardness test 10 trials were performed and the average of 6 consistent readings are taken as the outcome. 20 to 40% improvement in peak hardness is observed with intentional deformation over without deformation. The composite may be used for light duty cold working dies where bulk hardness and frictional characteristics are very important.

scholarly journals Effect of Ti Addition to Age Hardening Response of Al-10Zn-6MgxTi Alloy Produced by Squeeze Casting

2018 ◽  
Vol 186 ◽  
pp. 02009
Author(s):  
Dwi Ayu Nurcahyaningsih ◽  
Risly Wijanarko ◽  
Irene Angela ◽  
Bondan Tiara Sofyan
Keyword(s):  
Squeeze Casting ◽  
Solution Treatment ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hardness Measurement ◽  
Impact Testing ◽  
Age Hardening ◽  
Peak Hardness ◽  
7Xxx Alloy ◽  
Ti Addition

This research focused on investigating the effects of Ti addition on the age hardening response of Al 7xxx alloy for Organic Rankine Cycle (ORC) turbine impeller application in power plant generators. Al-10Zn-6Mg wt. % alloys were produced by squeeze casting with 0.02, 0.05, and 0.25 wt. % Ti addition. As-cast samples were homogenized at 400 °C for 4 h. Solution treatment was conducted at 440 °C for 1 h, followed by quenching and ageing at 130 °C for 200 h. Age hardening result was observed using Rockwell B hardness measurement. Other characterizations included impact testing, STA, optical microscopy, and SEM-EDS. Results showed that the addition of Ti in all content variations increased the as-cast hardness due to the diminution of secondary dendrite arm spacing (SDAS) values of the alloy. Ageing at 130 °C strengthened the alloys, however the addition of Ti was not found to affect neither peak hardness nor impact values of the alloy. Identities of second phases formed during solidification were found to be T (Mg32(Al,Zn)49), β (Al8Mg5), and TiAl3, while precipitates produced during ageing were GP Zone, η′, and η (MgZn2).

Effect of Ti Element on Microstructure and Properties of Cu-Cr Alloy

2015 ◽  
Vol 817 ◽  
pp. 307-311 ◽  
Author(s):  
Peng Chao Zhang ◽  
Jin Chuan Jie ◽  
Yuan Gao ◽  
Tong Min Wang ◽  
Ting Ju Li
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Spherical Shape ◽  
Precipitation Strengthening ◽  
Peak Hardness ◽  
Ti Alloy ◽  
Strengthening Mechanisms ◽  
Vacuum Melting ◽  
Solid Solution Strengthening ◽  
Solution Strengthening

The Cu-Cr and Cu-Cr-Ti alloy plates were prepared by vacuum melting and plastic deformation. The effect of slight Ti element on microstructure and mechanical properties of Cu-Cr alloy was discussed. The result shows that Cr particles with spherical shape precipitated from Cu matrix after aging. Plenty Ti atoms dissolved in the vicinity of Cr particles and there were still parts of solid solution Ti atoms in other regions. Improvements in peak hardness and softening resistance were achieved with the addition of Ti element in Cu-Cr alloy. The addition of 0.1 wt.% Ti element makes Cu-Cr alloy possess tensile strength of 565 MPa and hardness of 185.9 HV after aging at 450 °C for 120 min, which can be attributed to multiple strengthening mechanisms, i.e. work hardening, solid solution strengthening and precipitation strengthening.

scholarly journals Formation of microstructure and properties of Cu-3Ti alloy in thermal and thermomechanical processes

2017 ◽  
Vol 62 (1) ◽  
pp. 223-230 ◽  
Author(s):  
A. Szkliniarz
Keyword(s):  
Mechanical Properties ◽  
Electrical Conductivity ◽  
Plastic Deformation ◽  
Cold Working ◽  
Cold Deformation ◽  
Solution Treatment ◽  
Cold Plastic Deformation ◽  
Working Solution ◽  
Thermomechanical Processes ◽  
Selection Of

Abstract This paper presents the possibilities of forming the microstructure as well as mechanical properties and electrical conductivity of Cu-3Ti alloy (wt.%) in thermal and thermomechanical processes that are a combination of homogenising treatment, hot and cold working, solution treatment and ageing. Phase composition of the alloy following various stages of processing it into the specified semi-finished product was being determined too. It was demonstrated that the application of cold plastic deformation between solution treatment and ageing could significantly enhance the effect of hardening of the Cu-3Ti alloy without deteriorating its electrical conductivity. It was found that for the investigated alloy the selection of appropriate conditions for homogenising treatment, hot and cold deformation as well as solution treatment and ageing enables to obtain the properties comparable to those of beryllium bronzes.

scholarly journals The Effect of Heat Treatment on the Microstructure and Mechanical Properties of the Novel Low-Cost Ti-3Al-5Mo-4Cr-2Zr-1Fe Alloy

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3798
Author(s):  
Meng Sun ◽  
Dong Li ◽  
Yanhua Guo ◽  
Ying Wang ◽  
Yuecheng Dong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aging Time ◽  
Volume Fraction ◽  
Low Cost ◽  
Solution Treatment ◽  
Solution Temperature ◽  
The Novel ◽  
Α Phase ◽  
The Cost

In order to reduce the cost of titanium alloys, a novel low-cost Ti-3Al-5Mo-4Cr-2Zr-1Fe (Ti-35421) titanium alloy was developed. The influence of heat treatment on the microstructure characteristics and mechanical properties of the new alloy was investigated. The results showed that the microstructure of Ti-35421 alloy consists of a lamina primary α phase and a β phase after the solution treatment at the α + β region. After aging treatment, the secondary α phase precipitates in the β matrix. The precipitation of the secondary α phase is closely related to heat treatment parameters—the volume fraction and size of the secondary α phase increase when increasing the solution temperature or aging time. At the same solution temperature and aging time, the secondary α phase became coarser, and the fraction decreased with increasing aging temperature. When Ti-35421 alloy was solution-treated at the α + β region for 1 h with aging surpassing 8 h, the tensile strength, yield strength, elongation and reduction of the area were achieved in a range of 1172.7–1459.0 MPa, 1135.1–1355.5 MPa, 5.2–11.8%, and 7.5–32.5%, respectively. The novel low-cost Ti-35421 alloy maintains mechanical properties and reduces the cost of materials compared with Ti-3Al-5Mo-5V-4Cr-2Zr (Ti-B19) alloy.

Heat Treatment and Wear Characteristics of Al2O3 and TiC Particulate Reinforced AA6063 Al Alloy Hybrid Composites

2006 ◽  
Vol 128 (4) ◽  
pp. 891-894 ◽  
Author(s):  
M. Abdel Aziz ◽  
T. S. Mahmoud ◽  
Z. I. Zaki ◽  
A. M. Gaafer
Keyword(s):  
Heat Treatment ◽  
Sliding Wear ◽  
Hybrid Composites ◽  
Wear Behavior ◽  
Age Hardening ◽  
Peak Hardness ◽  
Dry Sliding Wear ◽  
Al Alloy ◽  
Composite Alloy ◽  
Al2o3 Particles

In this article, the heat treatment and dry sliding wear behavior of Al-based AA6063 alloy reinforced with both TiC and Al2O3 ceramic particles were studied. The particles were synthesized by self-propagating high temperature synthesis (SHS) technique. The prepared composite alloy contains 5vol.%Al2O3 and 5vol.% TiC particles. The composite alloy was prepared by vortex method. To attain the peak hardness values of the alloys, age hardening behavior of the monolithic alloy and also the composite alloy was investigated. The wear tests were performed at room temperature using a pin-on-disk type apparatus. The results showed that the addition of TiC and Al2O3 particles increases the hardness of the AA6063 Al alloy and at the same time accelerates the aging kinetics. The sliding wear properties of AA6063 Al alloy were significantly improved by the addition of TiC and Al2O3 particles.

Effects of T6 Age Hardening on Microstructure and Mechanical Properties of Al-Si-Cu Cast Aluminium Alloy

2013 ◽  
Vol 770 ◽  
pp. 88-91
Author(s):  
Amporn Wiengmoon ◽  
Pattama Apichai ◽  
John T.H. Pearce ◽  
Torranin Chairuangsri
Keyword(s):  
Electron Microscopy ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Aging Time ◽  
Artificial Aging ◽  
Solution Treatment ◽  
Hot Water ◽  
Age Hardening ◽  
Solution Treated ◽  
Cast Condition

Effects of T6 artificial aging heat treatment on microstructure, microhardness and ultimate tensile strength of Al-4.93 wt% Si-3.47 wt% Cu alloy were investigated. The T6 age hardening treatment consists of solution treatment at 500±5°C for 8 hours followed by quenching into hot water at 80°C and artificial aging at 150, 170, 200 and 230°C for 1-48 hours followed by quenching into hot water. Microstructure was characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). XRD and SEM revealed that the microstructure in the as-cast condition consists of primary dendritic α-Al, acicular-plate and globular forms of eutectic Si and intermetallic phases including globular Al2Cu and a flake-shape Al5FeSi. By T6 aging hardening, some intermetallics were dissolved and spheroidized. The volume fraction of eutectic phases in the as-cast, solution-treated, and solution-treated plus aging at 170°C for 24 hours is 17%, 12% and 10%, respectively. TEM results showed that precipitates in under-aging condition at 170° C for 6 hours are in the form of disc shape with the diameter in the range of 7-20 nm. At peak aging at 170°C for 24 hours, thin-plate precipitates with about 3-10 nm in thickness and 20-100 nm in length were found, lengthening to about 30-200 nm at longer aging time. The microhardness and ultimate tensile strength were increased from 71 HV0.05 and 227 MPa in the as-cast condition up to 140 HV0.05 and 400 MPa after solution treatment plus aging at 170°C for 24 hours, and decreased at prolong aging time.

Fatigue Behavior of Age-Hardening Cu-6Ni-1.5Si Alloys with Different Grain Sizes

2021 ◽  
Vol 1016 ◽  
pp. 125-131
Author(s):  
Masahiro Goto ◽  
T. Yamamoto ◽  
S.Z. Han ◽  
J. Kitamura ◽  
J.H. Ahn ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Fatigue Strength ◽  
Solution Heat Treatment ◽  
Fatigue Behavior ◽  
Fatigue Tests ◽  
The Other ◽  
Age Hardening ◽  
Grain Sizes ◽  
Thermomechanical Processes

On the thermomechanical treatments of Cu-Ni-Si alloy, cold-rolling (CR) before solution heat treatment (SHT) is commonly conducted to eliminate defects in a casting slab. In addition, a rolling is applied to reduce/adjust the thickness of casting slab before SHT. In a heavily deformed microstructure by CR, on the other hand, grain growth during a heating in SHT is likely to occur as the result of recrystallization. In general, tensile strength and fatigue strength tend to decrease with an increase in the grain size. However, the effect of difference in grain sizes produced by with and without CR before SHT on the fatigue strength is unclear. In the present study, fatigue tests of Cu-6Ni-Si alloy smooth specimens with a grain fabricated through different thermomechanical processes were conducted. The fatigue behavior of Cu-Ni-Si alloy was discussed.

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.

Sign in / Sign up

Export Citation Format

Share Document