Recycling of the Al Scrap: The Effect of Adding Inoculant Nb+B and Mg with Subsequent Heat-Treatment in the Mechanical Behavior of Al Alloy

A new perspective for the use of Al-Si alloys produced with recycled Al (with Fe>1%) in Gravity Die Casting (GDC) processes. To study the morphology of ß-Fe precipitates and the material’s mechanical properties were added the inoculate via Nb+B and the element Mg with subsequent heat treatment. The samples were cast in Al10Si1Fe0.35Mg alloy in a metal mould according to ASTM B108. The microstructure was analyzed with BSE-SEM and EDS. The work investigated the morphology of ß-Fe precipitates and their effects and interactions on the material’s mechanical properties. The combined effect resulted in reduced size and shape of ß-Fe precipitates, thereby improved higher yield strength (YS = 207.71 MPa), ultimate tensile strength (UTS = 300.35 MPa), and elongation of 4.66%, exceeding the strength and elongation limit values found in commercial alloys, such as ASTM A357 alloy, where the Fe content is low (max. 0.2%).

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Tensile Properties of Semi-Solid Die Cast AC4C Aluminum Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.680.11 ◽

2014 ◽

Vol 680 ◽

pp. 11-14

Author(s):

Ke Ren Shi ◽

Sirikul Wisutmethangoon ◽

Jessada Wannasin ◽

Thawatchai Plookphol

Keyword(s):

Heat Treatment ◽

Tensile Strength ◽

Aluminum Alloy ◽

Die Casting ◽

Casting Process ◽

Al Alloy ◽

Die Cast ◽

Die Casting Process ◽

Semi Solid ◽

Strength And Ductility

In this study, semi-solid Al-Mg-Si alloy (AC4C) was produced by using the Gas Induced Semi-Solid (GISS) die casting process. The tensile strength and ductility of the semi-solid die cast Al alloy (GISS-DC) after T6 heat treatment were investigated and compared with those of the conventional liquid die casting (CLDC). The microstructures of GISS-DC and CLDC observed by an optical microscopy were presented. The ultimate tensile strength (UTS) and yield strength (0.2% YS) of GISS-DC are compatible with those of the CLDC. However, the GISS-DC has better ductility than the CLDC, this may be due to the smaller and more globular primary α-Al phase and rounder shaped-Si particle microstructures presented in the GISS-DC. Common shrinkage pores and defects were also observed by SEM from the fracture surfaces of both alloys.

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Study on Microstructures and Mechanical Properties of Die Casting Mg-xGd-3Y-0.5Zr Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.44 ◽

2013 ◽

Vol 690-693 ◽

pp. 44-48

Author(s):

Feng Wang ◽

Zhi Wang ◽

Zheng Liu ◽

Ping Li Mao

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Solution Heat Treatment ◽

Die Casting ◽

Solution Treatment ◽

Small Variation ◽

Strength Increase ◽

Microstructures And Mechanical Properties ◽

Zr Alloys

In this paper, developed a non-aluminum die casting magnesium alloys were studied based on Mg-xGd-Y-Zr（x=6, 8, 12 wt.%）alloys in cold chamber press. The microstructures and mechanical properties of die casting GWK alloys have been investigated using OM, SEM, XRD, EDS and mechanical property test. The experimental results show that with increasing Gd content of Mg-xGd-Y-Zr alloys, the tensile strength increase, but elongation decrease. In particular, die casting GWK alloys after short-term and low-temperature solid solution treatment (T4) have a small variation in grain size and more uniform microstructures, and the second phases distribute at the grain boundaries in form of discontinuous rod shape or granule shape, which result in an obvious improvement in tensile mechanical properties of alloys. The Mg-12Gd-3Y-0.5Zr die casting alloy exhibit maximum tensile strength after solution heat treatment, and the value is 269MPa at room temperature. The effect of solution heat treatment on die casting Mg-xGd-Y-Zr alloys was also discussed.

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Process and Property of Superplastic Mould Forged AZ80 Wheel Hub

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.12 ◽

2014 ◽

Vol 788 ◽

pp. 12-16 ◽

Cited By ~ 4

Author(s):

Gao Feng Quan ◽

Ling Bao Ren

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Fuel Consumption ◽

Single Step ◽

Al Alloy ◽

Forging Process ◽

Alloy Wheel ◽

Remarkable Reduction ◽

Automobile Wheel

Automobile wheel hub of Mg alloy with single-step extrusion-forging process was developed, and the microstructure and mechanical properties after heat treatment were investigated. The forged hubs have a hub wall of as thin as 3mm, and 4-7kg lighter than that of Al alloy wheel hub with a same size and design of each wheel hub, that would lead remarkable reduction of fuel consumption. The tensile strength larger than 308 MPa, good corrosion fatigue and impacting resistance sampled from the hubs obtained.

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Investigating the Influence of Process Parameters on the Mechanical Properties of Extruded Aluminum Tubes by Cyclic Indentation Tests

Metals ◽

10.3390/met11050744 ◽

2021 ◽

Vol 11 (5) ◽

pp. 744

Author(s):

David Görzen ◽

Florian Patrick Schäfke ◽

Bastian Blinn ◽

Christian Klose ◽

Hans Jürgen Maier ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Process Condition ◽

Cyclic Hardening ◽

Extrusion Process ◽

Subsequent Heat Treatment ◽

Al Alloy ◽

Influence Of Process Parameters ◽

Indentation Tests ◽

Cyclic Indentation

Given the complex process condition, extruded aluminum (Al) alloy tubes show locally pronounced differences in microstructure and mechanical properties, which can be influenced by subsequent heat treatment. In the present study, cyclic indentation tests (CITs) were conducted on extruded Al alloy EN AW-6082 to locally determine hardness and cyclic hardening potential, which was complemented with light optical microscopy. To analyze the influence of extrusion process and subsequent heat treatment, the EN AW-6082 tubes investigated were manufactured with extrusion ratios Ψ of 13:1 and 22:1, both in as-extruded and T6 heat-treated conditions. The results obtained for the as-extruded state showed significant differences of the local mechanical properties and demonstrated that an increased Ψ leads to higher hardness, caused by more pronounced plastic deformation during the manufacturing process. Moreover, an increase of hardness and cyclic hardening potential was observed after a T6 heat treatment, which also reduced the difference in hardness between the different extrusion ratios. Additionally, the pronounced local differences in hardness and cyclic hardening potential correlated with the local microstructure. The results demonstrated that CITs enable the analysis of local mechanical properties of extruded EN AW-6082 profiles, resulting from different extrusions ratios as well as subsequent heat treatment.

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Effect of Injected Oxygen Amount on the Gas Porosity and Mechanical Properties of a Pore-Free Die-Cast Al–Si–Cu Alloy

Metals ◽

10.3390/met11111805 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1805

Author(s):

Ho-Jung Kang ◽

Ho-Sung Jang ◽

Seong-Hyo Oh ◽

Pil-Hwan Yoon ◽

Gyu-Heun Lee ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Die Casting ◽

High Vacuum ◽

Distribution Analysis ◽

T6 Heat Treatment ◽

Gas Porosity ◽

Before And After ◽

Die Castings

With the rise in the demand for eco-friendly and electric vehicles, welding and heat treatment are becoming very important to meet the necessary weight reduction, complexity, and high functionality of die castings. Pore-free (PF) die casting is an effective process that enables heat treatment and welding due to low gas porosities. Indeed, this process affords castings of low gas porosity, similar to those attained by high-vacuum die casting. In this study, we compared the gas porosities of different castings fabricated by PF die casting using varied injected oxygen amounts. The castings were all subjected to T6 heat treatment and analyzed by computed tomography (CT) to compare their microstructure and mechanical properties before and after T6 heat treatment. The results revealed that with the increasing injected oxygen amount, the gas porosity of the specimens decreased while their mechanical properties increased. In particular, the gas porosity was the lowest at 1.26 L. Moreover, the 1.26 L specimen displayed the best tensile strength, yield strength, and elongation results. Finally, Weibull distribution analysis revealed that the tensile strength and elongation repeatability and reproducibility increased with increasing injected oxygen amount.

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Effect of Heat Treatment on Microstructure and Mechanical Properties of Semi-Solid Formed Magnesium Alloy AZ91D

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.346 ◽

2010 ◽

Vol 148-149 ◽

pp. 346-352

Author(s):

Dong Nan Li ◽

Wen Zhe Chen ◽

Jun Tian

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Magnesium Alloy ◽

Die Casting ◽

Primary Phase ◽

T6 Heat Treatment ◽

Microstructure And Mechanical Properties ◽

Alloy Az91d ◽

Semi Solid

The semi-solid slurry of AZ91D magnesium alloy was prepared by twin-screw stirring mixer, the microstructure and mechanical properties of semi-solid formed magnesium alloy AZ91D produced by rheo-diecasting and conventional liquid die casting were investigated, respectively. The strengthen mechanism of the semi-solid formed magnesium alloy after heat treatment was analysed by EDS. The results show that the mechanical properties of semi-solid formed magnesium alloy can be enhanced markedly by T4 and T6 heat treatment, owing to decrease of the porosity and less segregation in casting, brittle eutectic compounds dissolves gradually into α-Mg matrix, and the primary phase α-Mg decomposes in the course of heat treatment. In as-cast state, the tensile strength, elongation and hardness of semi-solid formed magnesium alloy AZ91D are 222MPa, 2.3% and 74 HBS, respectively. In T4 heat treatment state, the tensile strength and elongation are increased by 13% and 210%, and in T6 heat treatment state, the tensile strength and hardness are increased by 11% and 16%. The mechanical properties of castings formed by conventional liquid die casting are deteriorated distinctly after T6 heat treatment due to its porosity and crack defects.

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Heat Treatment Evaluation for the Camshafts Production of ADI Low Alloyed with Vanadium

Metals ◽

10.3390/met11071036 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1036

Author(s):

Eduardo Colin García ◽

Alejandro Cruz Ramírez ◽

Guillermo Reyes Castellanos ◽

José Federico Chávez Alcalá ◽

Jaime Téllez Ramírez ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Ductile Iron ◽

Volume Fraction ◽

Energy Impact ◽

Treatment Conditions ◽

Mold Casting ◽

Grade 3 ◽

Good Agreement

Ductile iron camshafts low alloyed with 0.2 and 0.3 wt % vanadium were produced by one of the largest manufacturers of the ductile iron camshafts in México “ARBOMEX S.A de C.V” by a phenolic urethane no-bake sand mold casting method. During functioning, camshafts are subject to bending and torsional stresses, and the lobe surfaces are highly loaded. Thus, high toughness and wear resistance are essential for this component. In this work, two austempering ductile iron heat treatments were evaluated to increase the mechanical properties of tensile strength, hardness, and toughness of the ductile iron camshaft low alloyed with vanadium. The austempering process was held at 265 and 305 °C and austempering times of 30, 60, 90, and 120 min. The volume fraction of high-carbon austenite was determined for the heat treatment conditions by XRD measurements. The ausferritic matrix was determined in 90 min for both austempering temperatures, having a good agreement with the microstructural and hardness evolution as the austempering time increased. The mechanical properties of tensile strength, hardness, and toughness were evaluated from samples obtained from the camshaft and the standard Keel block. The highest mechanical properties were obtained for the austempering heat treatment of 265 °C for 90 min for the ADI containing 0.3 wt % V. The tensile and yield strength were 1200 and 1051 MPa, respectively, while the hardness and the energy impact values were of 47 HRC and 26 J; these values are in the range expected for an ADI grade 3.

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Engineering mechanical properties by controlling the microstructure of an Fe–Ni–Mn martensitic steel through pre-cold rolling and subsequent heat treatment

Materials Science and Engineering A ◽

10.1016/j.msea.2021.140760 ◽

2021 ◽

Vol 804 ◽

pp. 140760

Author(s):

Hamidreza Koohdar ◽

Pouya Hakimipour ◽

Hamid Reza Jafarian ◽

Terence G. Langdon ◽

Mahmoud Nili-Ahmadabadi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Cold Rolling ◽

Martensitic Steel ◽

Subsequent Heat Treatment

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Achievement of High Strength and Ductility in Al–Si–Cu–Mg Alloys by Intermediate Phase Optimization in As-Cast and Heat Treatment Conditions

Materials ◽

10.3390/ma13030647 ◽

2020 ◽

Vol 13 (3) ◽

pp. 647 ◽

Cited By ~ 4

Author(s):

Bingrong Zhang ◽

Lingkun Zhang ◽

Zhiming Wang ◽

Anjiang Gao

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Intermediate Phase ◽

High Strength ◽

Mg Alloys ◽

Artificial Ageing ◽

Treatment Conditions ◽

Eutectic Si

In order to obtain high-strength and high-ductility Al–Si–Cu–Mg alloys, the present research is focused on optimizing the composition of soluble phases, the structure and morphology of insoluble phases, and artificial ageing processes. The results show that the best matches, 0.4 wt% Mg and 1.2 wt% Cu in the Al–9Si alloy, avoided the toxic effect of the blocky Al2Cu on the mechanical properties of the alloy. The addition of 0.6 wt% Zn modified the morphology of eutectic Si from coarse particles to fine fibrous particles and the texture of Fe-rich phases from acicular β-Fe to blocky π-Fe in the Al–9Si–1.2Cu–0.4Mg-based alloy. With the optimization of the heat treatment parameters, the spherical eutectic Si and the fully fused β-Fe dramatically improved the ultimate tensile strength and elongation to fracture. Compared with the Al–9Si–1.2Cu–0.4Mg-based alloy, the 0.6 wt% Zn modified alloy not only increased the ultimate tensile strength and elongation to fracture of peak ageing but also reduced the time of peak ageing. The following improved combination of higher tensile strength and higher elongation was achieved for 0.6 wt% Zn modified alloy by double-stage ageing: 100 °C × 3 h + 180 °C × 7 h, with mechanical properties of ultimate tensile strength (UTS) of ~371 MPa, yield strength (YS) of ~291 MPa, and elongation to fracture (E%) of ~5.6%.

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