Micro-Structural Evolution of AlCu5MnCdVA Cast Aluminum Alloy by Semi-Solid Isothermal Annealing Process

Isothermal grain coarsening of AlCu5MnCdVA aluminum alloy prepared by permanent mould casting during semi-solid treatment process was studied. It was found that the relationship between the average diameter of α (Al) grains and the isothermal holding time fitted the formula r − r = K ⋅ t − − ' 3 0 3 , where the coarsening rate K’ varied with the holding temperature, which equaled to 4.288×10-10m3/s and 5.962×10-10m3/s at the holding temperature. A modified model of liquid film migration has been proposed for explaining of 622°C and 631°C respectively the coarsening rate variation with annealing temperature. The diffusion of the solutes as well as vacancies, and the grain boundary tension are responsible for the microstructure evolution of AlCu5MnCdVA cast alloy.

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Micro-Structural Evolution of AlCu5MnCdVA Cast Aluminum Alloy by Semi-Solid Isothermal Annealing Process

Advanced Materials Research - Advanced Materials and Processing ◽

10.4028/0-87849-463-4.489 ◽

2007 ◽

pp. 489-493 ◽

Cited By ~ 1

Author(s):

Guang Yu Yang ◽

Wan Qi Jie ◽

Qi Tang Hao ◽

Run Qiang Zhang

Keyword(s):

Aluminum Alloy ◽

Isothermal Annealing ◽

Structural Evolution ◽

Annealing Process ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Semi Solid

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Slurry Preparation and Hot Tearing Susceptibility of A201 Aluminum Alloy in Rheological Die Casting

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.285.311 ◽

2019 ◽

Vol 285 ◽

pp. 311-317 ◽

Cited By ~ 1

Author(s):

Jun Zhen Gao ◽

Qiang Zhu ◽

Da Quan Li ◽

Xiao Gang Hu ◽

Min Luo ◽

...

Keyword(s):

Aluminum Alloy ◽

Die Casting ◽

Mold Temperature ◽

Hot Tearing ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Intensification Pressure ◽

Semi Solid ◽

Index Value ◽

Hot Tearing Susceptibility

A201 alloy is the strongest cast aluminum alloy, but it is considered one of the most difficult aluminum alloys to cast due to its susceptibility to hot tearing during solidification. Semi-solid casting, which characterizes fine near-globular or non-dendritic grains and relatively narrow solidification range, is potential to reduce hot cracking tendency of alloys. In this present work, semi-solid slurries of A201 alloy were prepared using Swirled Enthalpy Equilibrium Device (SEED) technique and then injected into a self-designed high pressure hot tearing mold. The microstructures of A201 semi-solid slurries with different pouring temperatures were examined. Effects of different casting pressures on the hot tearing sensitivity of A201 have been investigated. This study finds that SEED is capable of producing satisfying A201 semi-solid slurries. Lower pouring temperatures produce A201 semi-solid slurries with finer and rounder grains as well as more uniform microstructure distribution. Increasing the intensification pressure significantly decreases the hot treating tendency of A201 alloy. When the pressure reaches to 90 MPa and the mold temperature of about 250 °C, the hot tearing susceptibility (HTS) index value is nearly zero, which means almost no surface cracks are found in the semi-solid A201 die casting parts.

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Microstructure as an essential aspect of EN AW 7075 aluminum alloy quality influenced by electromagnetic field during continuous casting process

Hemijska industrija ◽

10.2298/hemind201214006p ◽

2021 ◽

Vol 75 (1) ◽

pp. 31-37

Author(s):

Aleksandra Pataric ◽

Marija Mihailovic ◽

Branislav Markovic ◽

Miroslav Sokic ◽

Andreja Radovanovic ◽

...

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

Electromagnetic Field ◽

Aluminum Alloy ◽

Continuous Casting ◽

Cast Alloy ◽

Casting Process ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Continuous Casting Process

Microstructure assessment is crucial for the design and production of high-quality alloys such as cast aluminum alloy ingots. Along with the effect of a more homogeneous microstructure to result in much better mechanical properties, better as-cast alloy quality indicates a higher efficiency of the aluminum alloys production process. During the aluminum alloy solidification process many microstructural defects can occur, which deteriorate the mechanical properties and hence decrease the usability of such an ingot. Application of the electromagnetic field during the vertical continuous casting process significantly reduces occurrence of these defects. In the present study, EN AW 7075 alloy samples were cast with and without application of an electromagnetic field and examined regarding the microstructure, electrical conductivity, and changes in the phase composition. The obtained results clearly show that it is possible to decrease or avoid casting defects by the electromagnetic field application as verified by the microstructure characterization and quantification, electrical conductivity tests and differential thermal analysis (DTA).

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Metallographic Characterization of Porosity in A Cast Aluminum Alloy A356-T6

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.989 ◽

2007 ◽

Vol 546-549 ◽

pp. 989-994 ◽

Cited By ~ 1

Author(s):

Guang Ran ◽

Jing En Zhou

Keyword(s):

Aluminum Alloy ◽

Cast Alloy ◽

Area Fraction ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Maximum Area ◽

Secondary Dendrite Arm Spacing ◽

Pore Area ◽

Area Percentage

Microporosity in both HIPped and non-HIPped unmodified aluminum cast alloy A356-T6 was quantified metallographically in terms of its area, area percentage, length, sphericity and perimeter. In the studied materials, the secondary dendrite arm spacing (SDAS) values vary from 82μm to 96μm for both the HIPped and the non-HIPped castings. HIPping process significantly reduces porosity area fraction and pore sizes. The maximum area fraction of porosity and maximum pore area of the non-HIPped specimens are increased with increasing SDAS.

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Microstructural Evolution of ZL104 Aluminum Alloy Semi-Solid Billet Fabricated by RAP Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.285.234 ◽

2019 ◽

Vol 285 ◽

pp. 234-239

Author(s):

Yong Fei Wang ◽

Sheng Dun Zhao ◽

Chao Chen ◽

Peng Dong ◽

Peng Zhang

Keyword(s):

Aluminum Alloy ◽

Ostwald Ripening ◽

Isothermal Holding ◽

Isothermal Treatment ◽

Liquid Droplets ◽

Microstructural Coarsening ◽

Average Grain Size ◽

Cold Rolled ◽

Semi Solid ◽

Holding Temperature

In this study, ZL104 aluminum alloy supplied in cold rolled state was introduced in recrystallization and partial melting (RAP) process to fabricate semi-solid billets. During the RAP process, samples cut from cold rolled ZL104 aluminum plate were heated to different semi-solid temperatures, and the effects of isothermal treatment parameters on the microstructures of semi-solid billets were investigated. Results showed that, with the increase of isothermal holding temperature and time, both the average grain size and the shape factor were increased. Namely, the shape of solid grain was more and more spherical, but the size of solid grain was larger and larger, which may be not suitable for semi-solid forming. The size of liquid droplets was increased while the number of liquid droplets was decreased with increasing the isothermal holding temperature and time. Microstructural coarsening of solid grain were attributed to coalescence and Ostwald ripening mechanisms, however, the latter one played a more and more important role with the increase of isothermal holding time and temperature. Additionally, The optimal isothermal holding temperature and time are 570 °C and 5 min, respectively, and the coarsening rate constant is 1357.2 μm3/s at 570 °C.

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Evaluation of Additive Friction Stir Deposition for the Repair of Cast Al-1.4Si-1.1Cu-1.5Mg-2.1Zn

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4052759 ◽

2021 ◽

pp. 1-3

Author(s):

Peter Martin ◽

Allen Luccitti ◽

Mark Walluk

Keyword(s):

Aluminum Alloy ◽

Fatigue Testing ◽

Cast Alloy ◽

Repair Process ◽

Process Conditions ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Friction Stir ◽

Common Strategy ◽

Fusion Methods

Abstract The deposition of new alloy to replace a worn or damaged surface layer is a common strategy for repairing or remanufacturing structural components. Solid state methods, such as additive friction stir deposition (AFSD), mitigate the challenges associated with traditional fusion methods by depositing material at temperatures below the melting point. In this work, AFSD of aluminum alloy 6061-T6 was investigated as a means to fill machined grooves in a substrate of cast aluminum alloy Al-1.4Si-1.1Cu-1.5Mg-2.1Zn. The combination of machining and deposition simulate a repair in which damaged material is mechanically removed, then replaced using AFSD. Three groove geometries were evaluated by means of metallographic inspection, and tensile and fatigue testing. For the process conditions and groove geometries used in this study, the effective repair depth was limited to 2.3 – 2.6 mm; below that depth, the interface between the filler and substrate materials exhibited poor bonding associated with insufficient shear deformation. The deposited filler alloy closely matched the cast alloy substrate in both strength and hardness. In addition, the fatigue life during fully reversed axial fatigue testing was 66% of that predicted from historical data for comparable stress amplitudes. The results suggest that there is potential to utilize AFSD of 6061 as a viable repair process for cast Al-1.4Si-1.1Cu-1.5Mg-2.1Zn and other comparable alloys.

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