Effects of Si, Cu and Mg on the High-Temperature Mechanical Properties of Al-Si-Cu-Mg Alloy

The regression equation of the relationship between Si, Cu and Mg and the mechanical properties of Al-Si-Cu-Mg alloy was established according to the orthogonal experimental results. The microstructure of the Al-Si-Cu-Mg alloy was analyzed with scanning electron microscopy and energy dispersive spectroscopy. The results show that Si, Cu and Mg affected the mechanical properties (tensile strength and elongation rate) at 250 °C most significantly, minimally and negatively, respectively. The interactions between Cu, Mg and Si greatly reduced the high-temperature tensile strength owing to the formation of brittle and hard intermetallic Al5Mg8Cu2Si6 that behaved as the initial crack during stretching.

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The Effects of Laser Shock Peening on the Heat Resistance Property of A356 Aluminum Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.675.213 ◽

2013 ◽

Vol 675 ◽

pp. 213-218

Author(s):

Bin Fan ◽

Ji Wen Fan

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Temperature ◽

Compressive Stress ◽

Tensile Tests ◽

Residual Compressive Stress ◽

Laser Shock ◽

High Temperature Mechanical Properties ◽

High Level ◽

High Temperature Tensile

Laser shocking peening (LSP) is a good way to improving mechanical properties. The influence of laser shock peeening on the high temperature mechanical properties were studied by investigating the thermal stability of residual compressive stress induced by LSP and high temperature tensile properties. The samples treated by LSP were placed in annealing oven and insulated for 60mins under 200°C. The high temperature tensile tests were did on the MTS machine, the temperatures were 250°C. The results showed that the compressive residual stress induced by LSP were only released 19.7%, the residual compressive stress still remained at a high level, about-125.45MPa; the results from the high temperature tensile tests shows LSP can improved the elevated temperature tensile strength, the ultimate tensile strength（UTS） of LSP was from 319.79MPa to 252.63MPa，decreased 21%, but the UTS of untreated by LSP was from 283MPa to 130.18MPa，released 46.1%.

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Microstructure and High Temperature Tensile Properties of Mg–10Gd–5Y–0.5Zr Alloy after Thermo-Mechanical Processing

Metals ◽

10.3390/met8120980 ◽

2018 ◽

Vol 8 (12) ◽

pp. 980 ◽

Cited By ~ 5

Author(s):

Guohua Wu ◽

H. Jafari Nodooshan ◽

Xiaoqin Zeng ◽

Wencai Liu ◽

Dejiang Li ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Temperature ◽

Tensile Properties ◽

Test Temperature ◽

Mechanical Processing ◽

Twin Boundaries ◽

High Temperature Mechanical Properties ◽

High Temperature Tensile ◽

High Temperature Tensile Properties

The microstructure, high-temperature tensile properties and fracture behavior of the Mg-10Gd-5Y-0.5Zr alloy after thermo-mechanical processing (pre-tension between solution and aging treatment) were investigated. The pre-deformed alloy shows the accelerated aging kinetics compared to the un-deformed alloy. Microstructure of pre-deformed samples showed not only the homogeneous nucleation of the precipitate but also heterogeneous nucleation of precipitates on the dislocation and twin boundaries. Tensile results show that the pre-deformation enhanced the strength of the alloy, while it deteriorates the ductility of the alloy. The ultimate tensile strength (UTS) of the T6 treated un-deformed and pre-deformed alloy at room temperature are 331 MPa and 366 MPa, respectively. Tensile strength of the T6 treated alloy in both un-deformed and deformed conditions was enhanced by raising the test temperature and then reduced by further raising the test temperature. The higher strength of the pre-deformed alloy could be related to the higher density of the precipitates, which grow on the twin boundaries and can hinder the dislocation movement and strengthen the alloy. The results shows that thermo-mechanical processing can significantly improve the room- and high-temperature mechanical properties and enhance the formation of precipitates in Mg-10Gd-5Y-0.5Zr alloy, which can lead to wider application of the alloy in industries such as aerospace or powertrains that need better room- and high-temperature mechanical properties.

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The Influence of La and Ce on Microstructure and Mechanical Properties of an Al-Si-Cu-Mg-Fe Alloy at High Temperature

Metals ◽

10.3390/met11030384 ◽

2021 ◽

Vol 11 (3) ◽

pp. 384

Author(s):

Andong Du ◽

Anders E. W. Jarfors ◽

Jinchuan Zheng ◽

Kaikun Wang ◽

Gegang Yu

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Temperature ◽

Intermetallic Phases ◽

High Temperature Strength ◽

Thermal Expansion Mismatch ◽

Strengthening Mechanisms ◽

High Temperature Mechanical Properties ◽

Minor Contribution ◽

A Minor

The effect of lanthanum (La)+cerium (Ce) addition on the high-temperature strength of an aluminum (Al)–silicon (Si)–copper (Cu)–magnesium (Mg)–iron (Fe)–manganese (Mn) alloy was investigated. A great number of plate-like intermetallics, Al11(Ce, La)3- and blocky α-Al15(Fe, Mn)3Si2-precipitates, were observed. The results showed that the high-temperature mechanical properties depended strongly on the amount and morphology of the intermetallic phases formed. The precipitated tiny Al11(Ce, La)3 and α-Al15(Fe, Mn)3Si2 both contributed to the high-temperature mechanical properties, especially at 300 °C and 400 °C. The formation of coarse plate-like Al11(Ce, La)3, at the highest (Ce-La) additions, reduced the mechanical properties at (≤300) ℃ and improved the properties at 400 ℃. Analysis of the strengthening mechanisms revealed that the load-bearing mechanism was the main contributing mechanism with no contribution from thermal-expansion mismatch effects. Strain hardening had a minor contribution to the tensile strength at high-temperature.

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The Effect of Microalloying B on the High Temperature Mechanical Properties of Ti3Al

MRS Proceedings ◽

10.1557/proc-133-681 ◽

1988 ◽

Vol 133 ◽

Cited By ~ 1

Author(s):

Joseph W. Newkirk ◽

Gerald B. Feldewerth

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Tensile Properties ◽

Grain Refinement ◽

High Temperature Mechanical Properties ◽

High Temperature Tensile ◽

High Temperature Tensile Properties

ABSTRACTThe effect of adding boron to Ti3Al on the microstructure and high temperature tensile properties has been studied. Boron caused a large grain refinement that dominated the tensile properties at all temperatures. Particles of Ti2B were found in all of the boron containing alloys. TiB was found only at concentrations of 0.1% B or more.

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High-Temperature Mechanical Properties of As-Extruded ZK60

Materials Science Forum ◽

10.4028/www.scientific.net/msf.488-489.753 ◽

2005 ◽

Vol 488-489 ◽

pp. 753-758

Author(s):

Wei Wu ◽

C.M. Hong ◽

Li Jia Chen ◽

Yue Wang ◽

Lin Yang ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Strain Rate ◽

Initial Strain Rate ◽

Offset Yield Strength ◽

High Temperature Mechanical Properties ◽

Fracture Behaviors ◽

Elongation To Failure ◽

Zk60 Alloy ◽

High Temperature Tensile

High-temperature tensile and fracture behaviors of as-extruded ZK60 alloy were investigated. It was evident from the experiments that with decreasing temperature and increasing strain rate, the 0.2% offset yield strength and ultimate tensile strength of the alloy increased while the elongation to failure decreased. The flowing stress of as-extruded ZK60 alloy during plastic deformation was proportioned to the reciprocal of temperature. At the initial strain rate of 5×10-4s-1, the calculated active energy at 300°C was about 93.4 kJ/mol.

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Study on the Relationship between High Temperature Mechanical Properties and Precipitates Evolution of 7085 Al Alloy after Long Time Thermal Exposures

Metals ◽

10.3390/met11091483 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1483

Author(s):

Jinxin Zang ◽

Pan Dai ◽

Yanqing Yang ◽

Shuai Liu ◽

Bin Huang ◽

...

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

High Temperature ◽

Tensile Properties ◽

Volume Fraction ◽

Al Alloy ◽

Strengthening Effect ◽

Nano Scale ◽

High Temperature Mechanical Properties ◽

The Relationship

The requirement for 7085 Al alloy as large airframe parts has been increasing due to its low quenching sensitivity and high strength. However, the relationship between high temperature mechanical properties and the evolution of precipitates in hot environments is still unclear. In this work, thermal exposure followed by tensile tests were conducted on the 7085 Al alloy at various temperatures (100 °C, 125 °C, 150 °C and 175 °C). Variations of hardness, electrical conductivity and tensile properties were investigated. The evolution of the nano scale precipitates was also quantitatively characterized by transmission electron microscopy (TEM). The results show that the hardness and electrical conductivity of the alloy are more sensitive to the temperature than to the time. The strength decreases continuously with the increase of temperature due to the transformation from η′ to η phase during the process. Furthermore, the main η phase in the alloy transformed from V3 and V4 to V1 and V2 variants when the temperature was 125 °C. Additionally, with increasing the temperature, the average precipitate radius increased, meanwhile the volume fraction and number density of the precipitates decreased. The strengthening effect of nano scale precipitates on tensile properties of the alloy was calculated and analyzed.

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The Effect of the Cooling Rates on the Microstructure and High-Temperature Mechanical Properties of a Nickel-Based Single Crystal Superalloy

Materials ◽

10.3390/ma13194256 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4256

Author(s):

Xiao-Yan Wang ◽

Meng Li ◽

Zhi-Xun Wen

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Single Crystal ◽

Solution Treatment ◽

Single Crystal Superalloy ◽

Air Cooling ◽

Strengthening Effect ◽

Cooling Rates ◽

High Temperature Mechanical Properties ◽

High Temperature Tensile

The as-cast alloy of nickel-based single-crystal superalloy was used as the research object. After four hours of solution treatment at 1315 °C, four cooling rates (water cooling (WC), air cooling (AC) and furnace cooling (FC1/FC2)) were used to reduce the alloy to room temperature. Four different microstructures of nickel-based superalloy material were prepared. A high-temperature tensile test at 980 °C was carried out to study the influence of various rates on the formation of the material’s microstructure and to further obtain the influence of different microstructures on the high-temperature mechanical properties of the materials. The results show that an increase of cooling rate resulted in a larger γ′ phase nucleation rate, formation of a smaller γ′ phase and a greater number. When air cooling was used, the uniformity of the γ′ phase and the coherence relationship between the γ′ phase and the γ phase were the best. At the same time, the test alloy had the best high-temperature tensile properties, and the material showed a certain degree of plasticity. TEM test results showed that the test alloy mainly blocked dislocations from traveling in the material through the strengthening effect of γ′, and that AC had the strongest hindering effect on γ′ dislocation movement.

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Properties of Bamboo Fiber Reinforced Cornstarch-Based Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.200.237 ◽

2012 ◽

Vol 200 ◽

pp. 237-242

Author(s):

Guang Sheng Zeng ◽

Rui Zhen Lin ◽

Cong Meng ◽

Lei Chen

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Temperature ◽

Extrusion Process ◽

Elongation Rate ◽

Bamboo Fiber ◽

Physical Methods ◽

Plasticizer Content ◽

Different Content ◽

Properties Of Composites

In this paper the composites made of cornstarch and PVA as matrix, bamboo fiber as reinforcement, glycerol and urea as mixed plasticizer were prepared through the extrusion molding. By physical methods, the effects of cornstarch, bamboo fiber, PVA and mixed plasticizer on the mechanical properties of composites were investigated. SEM was used to observe the influence of different content of mixed plasticizer in cornstarch. The results showed that an increase in mixed plasticizer content from 10% to 40% in cornstarch did improve the mechanical properties of the composites compared without mixed plasticizer, and when the mixed plasticizer (wt-glycerol: wt-urea=2:1) content was 30% to cornstarch, the composite showed the highest tensile strength and elongation rate. Composites made from 20% of bamboo fiber, 30% of cornstarch, 50% of PVA and 30% of mixed plasticizer to cornstarch gave the best tensile strength (15.8N). Glycerol and urea could permeate the cornstarch molecules and plasticize it under high temperature and shearing in the extrusion process.

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Effect of Rare Earth Er on Microstructure and Mechanical Properties of Cast Al-Si-Mg Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.202 ◽

2017 ◽

Vol 893 ◽

pp. 202-206 ◽

Cited By ~ 2

Author(s):

Qing Lin Li ◽

Bin Qiang Li ◽

Jin Bao Li ◽

Chao Fen Zhang ◽

Ye Feng Lan

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Rare Earth ◽

Electron Probe ◽

Mg Alloy ◽

Chinese Script ◽

Eutectic Si ◽

Scanning Electron

It is well known that Al-Si-Mg alloy can form Chinese script eutectic Mg2Si and large blocky primary Mg2Si phases. In this paper, the microstructures and mechanical properties of cast Al-18Si-10Mg-xEr (x=0, 0.3, 0.5, 0.8 and 1.0 wt.%) alloy were investigated. The as-cast samples were characterized by optical microscopy (OM), scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) with wavelength dispersive spectroscopic (WDS). The results show that the morphology of primary Mg2Si changed from large block or Chinese script-like to fine block with increasing of Er contents from 0.3% to 1.0%., and the morphology of eutectic Si phases transformed into fine coral-like fibrous structure and the size of eutectic Si dramatically decrease. The mechanical properties were researched by tester with different concentration of rare earth Er. It was found that the ultimate tensile strength and hardness increased by 32.1% and 21.4%, respectively.

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