Wear and Mechanical Behaviour of Hypo-Eutectic Al-7%Si-0.5%Mg Alloy (A357) Reinforced with Al2O3 Particles

In this study, A357 (Al-7%Si-0.5%Mg) alloy/Al2O3 composites with various volume fractions (4%, 8%, 10%) were prepared by using permanent mould casting. In addition, A357 alloys were cast for comparison purposes. The alloys and composites were given a T6 heat treatment process (solution treatment and artificial ageing), Also microstructure, hardness and tensile properties of these composites were evaluated and compared. In addition, tribological properties of these composites were evaluated using a Pin-on-Disc apparatus at a constant sliding velocity of 1m/s and pressure of 0.35 MPa. The microstructure of the composites shows homogenous distribution of Al2O3 plate-like particles in the Al matrix except in the A357/10%Al2O3 composite. The wear and mechanical properties of composites improve with increasing the volume fraction of Al2O3 upto 8% and then decreases. Particularly, mechanical properties of the A357/10%Al2O3 composite are lower than the alloy indicating that the critical volume fraction of Al2O3 reinforcement in the A357 alloy is 8%. Wear morphology studies show that abrasive and delamination wear are extensive in the alloy whereas the slight delamination wear with some abrasive grooves are found in the composites.

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Fabrication and Characterization of Al-0.4%Si-0.5%Mg - SiCp Using Permanent Mould Casting Technique

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.867.34 ◽

2017 ◽

Vol 867 ◽

pp. 34-40 ◽

Cited By ~ 1

Author(s):

Adithya Parthasarathy ◽

L. Avinash ◽

K.N. Varun Kumar ◽

Basavaraj Sajjan ◽

S. Varun

Keyword(s):

Heat Treatment ◽

Tribological Properties ◽

Solution Treatment ◽

Weight Fraction ◽

Constant Load ◽

Artificial Ageing ◽

Casting Technique ◽

Mechanical And Tribological Properties ◽

Pin On Disc ◽

Mould Casting

Production of A6063/SiC composite with various weight fractions (3%, 6%, 9%) were prepared by using permanent mould casting was investigated. The preferred mean particle size of SiC is 60 μm. In addition, A6063 alloys were cast for comparison purposes. The alloys and composites were given a T6 heat treatment process (solution treatment at 520 °C, water quenching at room temperature and artificial ageing at 180 °C), Also Microstructure, hardness and tensile properties of these composites were evaluated and compared. In addition, tribological properties of these composites were evaluated using a Pin-on-Disc apparatus with various parameters (constant load of 10N and varying velocities as follows 0.5m/s, 1m/s, 1.5m/s, 2m/s) .The microstructure of the composites shows homogenous distribution of SiC particles in the Al matrix except in the A6063/9% SiC composite. The wear and mechanical properties of composites improve with increasing the weight fraction of SiC Wear morphology studies show that higher wear rate in case of unreinforced specimen compared to heat treated composites. Whereas with the increase in SiC content, the material tends to fail in brittle mode. The aim of present study is to evaluate the effect of heat treatment on the mechanical and tribological properties of aluminum alloy A6063 /SiC metal matrix composite.

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The Effect of Ceramic Reinforcement on the Microstructure, Mechanical Properties and Tribological Behavior of Al-7.5%Si-0.5%Mg Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.867.3 ◽

2017 ◽

Vol 867 ◽

pp. 3-9

Author(s):

L. Avinash ◽

Hemanth Kumar ◽

Adithya Parthasarathy ◽

K.N. Varun Kumar ◽

Basavaraj Sajjan

Keyword(s):

Mechanical Properties ◽

Cast Alloy ◽

Weight Fraction ◽

Hardened Layer ◽

Mg Alloy ◽

A357 Alloy ◽

Critical Weight ◽

Weight Percentage ◽

Casting Technique ◽

Pin On Disc

In this investigation, A357 (Al-7.5%Si-0.5%Mg) alloy/Al2O3 composites with various weight fractions (4%, 8%, 10%) were prepared by using permanent mould casting. In addition, A357 alloys were cast for comparison purposes. Microstructure, hardness and tensile properties of these composites were evaluated and compared with as-cast alloy. In addition, tribological properties of these composites were evaluated using a Pin-on-Disc apparatus at a constant sliding velocity of 1m/s and pressure of 0.35 MPa. The microstructure of the composites shows homogenous distribution of Al2O3 plate-like particles in the Al matrix except in the A357/10%Al2O3 composite. The wear and mechanical properties of composites improve with increasing the weight percentage of Al2O3 upto 8% and then decreases. Particularly, mechanical properties of the A357/10%Al2O3 composite are lower than the alloy indicating that the critical weight fraction of Al2O3 reinforcement in the A357 alloy is 8%. Wear morphology studies show that higher wear rate in case of unreinforced specimen was associated with higher thickness of hardened layer and consequent delamination of wear debris from the surface which was confirmed by optical and scanning electron micrography.Whereas ductile and brittle mode of fracture is observed in Fractographic observation of composite. The present paper highlights the salient features of casting technique and characterization of aluminum alloy A357 and alumina metal matrix composite.

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

Materials ◽

10.3390/ma13173798 ◽

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.

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Microstructure Evolution and Mechanical Properties of AZ80 Mg Alloy during Annular Channel Angular Extrusion Process and Heat Treatment

Materials ◽

10.3390/ma12244223 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4223 ◽

Cited By ~ 3

Author(s):

Xi Zhao ◽

Shuchang Li ◽

Fafa Yan ◽

Zhimin Zhang ◽

Yaojin Wu

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Microstructure Evolution ◽

Solution Treatment ◽

Aging Treatment ◽

Annular Channel ◽

Mg Alloy ◽

Strengthening Effect ◽

Β Phase ◽

Angular Extrusion

Microstructure evolution and mechanical properties of AZ80 Mg alloy during annular channel angular extrusion (350 °C) and heat treatment with varying parameters were investigated, respectively. The results showed that dynamic recrystallization of Mg grains was developed and the dendritic eutectic β-Mg17Al12 phases formed during the solidification were broken into small β-phase particles after hot extrusion. Moreover, a weak texture with two dominant peaks formed owing to the significant grain refinement and the enhanced activation of pyramidal <c + a> slip at relative high temperature. The tension tests showed that both the yield strength and ultimate tensile strength of the extruded alloy were dramatically improved owing to the joint strengthening effect of fine grain and β-phase particles as compared with the homogenized sample. The solution treatment achieved the good plasticity of the alloy resulting from the dissolution of β-phases and the development of more equiaxed grains, while the direct-aging process led to poor alloy elongation as a result of residual eutectic β-phases. After solution and aging treatment, simultaneous bonding strength and plasticity of the alloy were achieved, as a consequence of dissolution of coarse eutectic β-phases and heterogeneous precipitation of a large quantity of newly formed β-phases with both the morphologies of continuous and discontinuous precipitates.

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Compressive deformation and damage of Mg-based metallic glass interpenetrating phase composite containing 30–70 vol% titanium

Journal of Materials Research ◽

10.1557/jmr.2010.0272 ◽

2010 ◽

Vol 25 (11) ◽

pp. 2192-2196 ◽

Cited By ~ 4

Author(s):

Yu Sun ◽

Haifeng Zhang ◽

Aimin Wang ◽

Huameng Fu ◽

Zhuangqi Hu ◽

...

Keyword(s):

Mechanical Properties ◽

Metallic Glass ◽

Fracture Strength ◽

Deformation Behavior ◽

Volume Fraction ◽

Critical Volume ◽

Strengthening Mechanisms ◽

Phase Volume ◽

Phase Volume Fraction ◽

Critical Volume Fraction

Mg-based metallic glass interpenetrating phase composites (IPCs) containing 30–70 vol% titanium was fabricated in this study. The effects of reinforced phase volume fraction and interspace on the mechanical properties were investigated systematically. With increasing the volume fraction of titanium, the fracture strength and strain increased up to 1860 MPa and 44%, respectively. The results showed that the critical volume fraction (around 40%) of Ti metal should be required for significantly improving plasticity of IPC. Decreasing the interspace of the titanium phase could lead to enhancement of yield and fracture strength. The deformation behavior and strengthening mechanisms were discussed in detail.

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Effect of Boron Addition on Microstructure and Mechanical Properties of AZ84 Mg Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.653 ◽

2016 ◽

Vol 879 ◽

pp. 653-658

Author(s):

Ju Hyun Won ◽

Seok Hong Min ◽

Tae Kwon Ha

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Solution Treatment ◽

Treatment Temperature ◽

Mg Alloy ◽

Solution Treatment Temperature ◽

Solid Solution Treatment ◽

Microstructure And Mechanical Properties ◽

Peak Aging ◽

Aging Kinetics

Effect of B addition on the microstructure and mechanical properties of AZ84 Mg alloy was investigated in this study. Through calculation of phase equilibria of AZ84 Mg alloy, carried out by using FactSage® and FTLite database, solution treatment temperature was decided as temperature of 330oC, where supersaturated solid solution can be obtained. Solid solution treatment of AZ84 Mg alloy was successfully conducted at 330oC and supersaturated microstructure with all almost all phases resolved into matrix was obtained. After solution treatment, hot rolling was successfully conducted by reduction of 60%. Compression and tension tests were carried out at room temperature on the samples in as-cast, solution treated, hot-rolled and subsequently recrystallized states. After solid solution treatment, each alloy was soaked at temperatures of 180 and 200oC for time intervals from 1 min to 48 hrs and hardness of each condition was measured by micro-Vickers method. Peak aging conditions were deduced as at the temperature of 200 oC for 10 hrs for ZA84 Mg alloy. By addition of boron, aging kinetics was expedited and strength was enhanced.

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Effect of Solution Treatment on Microstructure and Mechanical Properties of Hot-Extruded Cu-15Ni-8Sn Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1156 ◽

2017 ◽

Vol 898 ◽

pp. 1156-1162

Author(s):

Xun Wang ◽

Chao Zhao ◽

Yan Gen Yu ◽

Zong Qiang Luo ◽

Wei Wen Zhang

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Solution Treatment ◽

Optical Microscope ◽

Solution Time ◽

Solution Temperature ◽

Scanning Calorimetry ◽

Annealing Twins ◽

Optimum Solution ◽

Electronic Microscope

The effects of solution treatment on the microstructure evolution of hot-extruded Cu-15Ni-8Sn alloy were investigated by optical microscope (OM), scanning electronic microscope (SEM), differential scanning calorimetry (DSC) and tensile testing, and the effects of solution temperature and time on the mechanical properties of the alloys were analyzed. The results indicated that, the γ-phases precipitated at first and then dissolved with the extension of the solution time during solutionizing at 800 C,the volume fraction of theγ-phase reached its peak at about 1h. However when solutionizing at 860°C, theγ-phase solely dissolved gradually with the extension of the solution time . In addition, a small amount of annealing twins appeared intragranular in the process of solution treatment. The γ-phase dissolution and the grain growth of α (Cu) were the main softening factors of the alloy during the solution treatment. Through overall consideration, the optimum solution treatment was annealing at 840°Cfor 1 h.

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Effects of Natural Ageing on T6 Heat Treated Rheocasts of 319S Aluminum Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.256.58 ◽

2016 ◽

Vol 256 ◽

pp. 58-62 ◽

Cited By ~ 1

Author(s):

Kang Du ◽

Qiang Zhu ◽

Da Quan Li

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Aluminium Alloys ◽

Solution Treatment ◽

Treatment Temperature ◽

Solution Treatment Temperature ◽

Artificial Ageing ◽

Natural Ageing ◽

T6 Heat Treatment ◽

Semi Solid

T6 heat treatment is an effective method to improve the comprehensive properties of Al-Si-Cu-Mg series aluminium alloys. Solution treatment temperature and time, quench process and media, as well as artificial ageing temperature and time are the key factors to determine mechanical properties. Besides these factors, natural ageing, i.e. the holding time between quenching and the starting of artificial treatment at ambient temperature was observed to be significant affect mechanical properties of the aluminium alloys. This effect on semi solid processed aluminium alloys was lack of investigations as the semi solid process produces T6 treatable and weldable components. The present paper focuses on the change regularity of hardness and precipitate behaviour of semi-solid 319S aluminium alloy under different natural ageing (NA) treatment additional to standard T6. Density and morphology of hardening precipitates are analysed using TEM, and the influence mechanism of NA during T6 heat treatment will be discussed. The results show that NA has a positive influence on mechanical properties of the rheo-cast 319S alloy.

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Microstructure and Toughness of an AZ80 Mg Alloy Processed by ECAP and Ageing Treatment

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.475 ◽

2010 ◽

Vol 667-669 ◽

pp. 475-480

Author(s):

De Liang Yin ◽

Xin Chen ◽

Jing Tao Wang

Keyword(s):

Mechanical Properties ◽

Mg Alloy ◽

Artificial Ageing ◽

Combined Effects ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Continuous Precipitation ◽

Tension Tests ◽

Az80 Alloy ◽

Tensile Toughness

An extruded AZ80 Mg alloy was subjected to ECAP and subsequent artificial ageing to investigate the influences of ECAP passes and ageing conditions on the mechanical properties. The microstructures and mechanical properties were characterized by optical microscopy (OM), scanning electronic microscopy (SEM) and uniaxial tension tests. The static toughness values were calculated to evaluate the combined effects of ECAP and artificial ageing on the toughness. It is indicated that combination of ECAP and ageing at 300oC for 8h can significantly increase the toughness of as-extruded AZ80 alloy by 43%. The remarkable twinning and uniform dimples due to the continuous precipitation should be responsible for the increased tensile toughness.

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Effects of the Mg/Si Ratio on Microstructure, Mechanical Properties, and Precipitation Behavior of Al–Mg–Si–1.0 wt %-Zn Alloys

Materials ◽

10.3390/ma11122591 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2591 ◽

Cited By ~ 6

Author(s):

Yong Li ◽

Guanjun Gao ◽

Zhaodong Wang ◽

Hongshuang Di ◽

Jiadong Li ◽

...

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Solution Treatment ◽

Hardness Test ◽

Strengthening Effect ◽

Precipitation Behavior ◽

Scanning Calorimetry ◽

First Choice ◽

The Matrix ◽

Zn Alloys

Aluminum alloys are widely used as first-choice materials for lightweight automotive applications. It is important that an alloy have a balance between strength and formability. In this study, the alloys were melted, cast, hot rolled, and cold rolled into 1 mm-thick sheets. The microstructure, mechanical properties, and precipitation behavior of Al–Mg–Si–1.0 wt %-Zn alloys with Mg/Si ratios of 0.5, 1, and 2 after solution treatment were studied using optical and electron microscopy, a tensile test, the Vickers hardness test, and differential scanning calorimetry. The results showed that a high density and number of Al–Fe–Si particles were observed in the matrix, thus causing the formation of more homogeneous and smaller recrystallized grains after treatment with the solution. In addition, a higher volume fraction of cubeND and P-types texture components formed during solution treatment. Also, a high r value and excellent deep drawability were achieved in the medium-Mg/Si-ratio alloy. The formation of denser strengthening precipitates led to a better paint-bake hardening effect in comparison with the other two alloys. Furthermore, the precipitation kinetics were enhanced by the addition of Si, and the addition of Zn did not alter the precipitation sequence of the Al–Mg–Si alloy. The dual-phase strengthening effect was not achieved in the studied alloys during paint-bake treatment at 175 °C.

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