Numerical/experimental investigation of bulge tests on a localized laser heat-treated magnesium alloy AZ31 sheet

Lightweight alloys can be considered among the most promising materials thanks to their capability to reduce the environmental impact, without affecting mechanical properties. In addition, when very complex shapes are required, a viable strategy could be represented by the adoption of non-conventional forming processes applied to tailored blanks that allow to obtain local variation of the material properties. In fact, referred to the Mg alloys, both grain size and temperature strongly influence the deformation behavior, as well as the mechanical properties. In this work, the effects of a selective Laser Heat Treatment (LHT) on a Mg AZ31B-H24 alloy sheet were investigated both numerically and experimentally. Experimental tests were performed, using a Diode laser source and keeping a square spot stationary in the center of the sample. The microstructure evolution was evaluated by means of light microscopy. Subsequently, the heat-treated samples were subjected to bulge tests under superplastic conditions (450°C) and using pressurized argon gas. The experimental microstructure distributions obtained were used for the numerical bulge tests analyses performed in the same conditions of the experimental trials. Experimental LHT results showed the capability to locally modify the microstructure when suitable temperatures and interaction times are selected. Regarding the bulge tests, the obtained results showed the possibility to effectively affect the thickness distribution of the final shapes.

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Formability of Ultrafine-Grained AA6016 Sheets Processed by Accumulative Roll Bonding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.504-506.575 ◽

2012 ◽

Vol 504-506 ◽

pp. 575-580 ◽

Cited By ~ 3

Author(s):

Tina Hausöl ◽

Christian W. Schmidt ◽

Verena Maier ◽

Wolfgang Böhm ◽

Hung Nguyen ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Laser Heat Treatment ◽

Bending Tests ◽

Roll Bonding ◽

Laser Heat ◽

Heat Treated ◽

Ultrafine Grained ◽

Ultrafine Grained Microstructure ◽

Bending Behaviour

Aluminium alloy AA6016 was accumulative roll bonded up to eight cycles in order to produce an ultrafine-grained microstructure. The formability of these sheets was investigated by means of bending tests. Furthermore the influence of a local laser heat treatment at the bending edge is observed. The strength of the UFG samples is increased by a factor of around two compared to the conventionally grained T4 condition which also results in up to 50 % higher punch forces needed for bending of ARB processed samples. An anisotropic bending behaviour is observed. By applying a tailored laser heat treatment along the bending edge prior to the bending tests a local recrystallization and recovery at the deformation zone of the samples is achieved. Thus, ductility is increased locally whereby bending to an angle of 80° is possible with lower forming forces compared to the non-heat treated specimens. The results are compared to previous studies on mechanical properties and formability investigations of ARB processed AA6016.

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TEXTURE AND FORMABILITY DEVELOPMENT OF ASYMMETRY ROLLED AA 3003 AL ALLOY SHEET

International Journal of Modern Physics B ◽

10.1142/s0217979208051339 ◽

2008 ◽

Vol 22 (31n32) ◽

pp. 5895-5900 ◽

Cited By ~ 6

Author(s):

INSOO KIM ◽

SAIDMUROD AKRAMOV ◽

HAE BONG JEONG

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Plastic Strain ◽

Research Work ◽

Heat Treating ◽

Alloy Sheet ◽

Al Alloy ◽

Fine Grain ◽

Heat Treated ◽

Crystallographic Orientations

The physical, mechanical properties and formability of sheet metal depend on preferred crystallographic orientations (texture). In this research work, we investigated texture development and formability of AA 3003 aluminum alloy sheets after asymmetry rolling and subsequent heat treatment. After asymmetry rolling, the specimens showed fine grain size. We also investigated the change of the plastic strain ratios after asymmetry rolling and subsequent heat-treating condition. The plastic strain ratios of asymmetrically rolled and subsequent heat treated samples are 1.5 times higher than the initial AA 3003 Al alloy sheets. These could be attributed to the formation of ND//<111> texture component through asymmetry rolling in Al sheet.

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Solidification Microstructure and Mechanical Properties of Hot Rolled and Annealed Mg Sheet Produced through Twin Roll Casting Route

Materials Science Forum ◽

10.4028/www.scientific.net/msf.690.331 ◽

2011 ◽

Vol 690 ◽

pp. 331-334 ◽

Cited By ~ 17

Author(s):

M. Aljarrah ◽

Elhachmi Essadiqi ◽

D.H. Kang ◽

In Ho Jung

Keyword(s):

Mechanical Properties ◽

Fuel Efficiency ◽

Direct Chill ◽

Alloy Sheet ◽

Process Conditions ◽

Twin Roll Casting ◽

Roll Casting ◽

Average Grain Size ◽

Az31 Sheet ◽

Twin Roll

The use of wrought magnesium for automobile structural components is an important component of the mass reduction strategy for automobiles to improve their fuel efficiency. Compared to Direct chill casting, Twin Roll Casting (TRC) allows major reduction of hot rolling steps in the production of Mg sheet due to the thin thickness of the as-cast strip. This TRC route can substantially reduce the time and cost to produce Mg alloy sheet product. In this work, AZ31 magnesium alloy was casted to 5 and 6 mm thick strips under different process conditions. Microstructure of these strips was analyzed using optical microscopy, SEM and EPMA. TRC strip was annealed under two different conditions: 2 hours at 330 and 1 hour at 400°C. It has been found that heat treatment at 400°C for 1 hour reduces centerline segregation significantly. TRC strips were rolled down to 2 mm and annealed at 450°C for 2 minutes. The average grain size was 4-6 µm and mechanical properties were comparable with commercial AZ31 sheet.

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Mechanical Properties of Laser Heat Treated 6 mm Thick UHSS-Steel

10.1063/1.3589699 ◽

2011 ◽

Cited By ~ 5

Author(s):

Antti Järvenpää ◽

Kari Mäntyjärvi ◽

Marion Merklein ◽

Antti määttä ◽

Mikko Hietala ◽

...

Keyword(s):

Mechanical Properties ◽

Laser Heat ◽

Heat Treated

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Effects of laser heat treatment on mechanical properties of ceramic coated steelsPart 2 – Fracture strength of laser heat treated ceramic thin film

Materials Research Innovations ◽

10.1179/1432891713z.000000000348 ◽

2014 ◽

Vol 18 (sup1) ◽

pp. S1-17-S1-21

Author(s):

H. Tanabe ◽

K. Ogawa ◽

Y. Izumi ◽

T. Takamatsu ◽

H. Nakagawa ◽

...

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Heat Treatment ◽

Fracture Strength ◽

Laser Heat Treatment ◽

Laser Heat ◽

Heat Treated ◽

Ceramic Thin Film

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An Investigation into Mechanical Properties of Ductile Cast Iron with Different Heat Treatment Processes

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.13672 ◽

2019 ◽

Vol 63 (3) ◽

pp. 183-187

Author(s):

Romany R. Moussa ◽

Amer E. Ali ◽

Ragab K. Abdel-Magied ◽

Mohamed N. Elshiekh

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Cast Iron ◽

Wear Rate ◽

Experimental Tests ◽

Mechanical Tests ◽

Heat Treatments ◽

Ductile Cast Iron ◽

Treatment Processes ◽

Heat Treated

The mechanical properties as well as microstructure of the ductile cast iron (DCI) are most likely affected by heat treatments. In this work, the mechanical properties of different heat treated of DCI alloy were investigated. Two heat treatment (HT) processes were conducted for DCI; austempering and quenching followed by lower tempering. The melted alloy of DCI was poured in Y-block, from which the specimens of the mechanical tests were prepared. Experimental tests were carried out to investigate the effect of these HT processes on the mechanical properties. A comparison between mechanical properties due to HT and as cast DCI are presented and discussed. The results showed that there is a difference in microstructure, homogeneity, wear rate and compression of DCI based on the conducted heat treatment.

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The Effect of Differential Speed Rolling on Microstructure and Mechanical Properties of an AZ31 Alloy Sheet

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.116-117.235 ◽

2006 ◽

Vol 116-117 ◽

pp. 235-238 ◽

Cited By ~ 2

Author(s):

Ha Guk Jeong ◽

Y.G. Jeong ◽

Duk Jae Yoon ◽

Seo Gou Choi ◽

Woo Jin Kim

Keyword(s):

Mechanical Properties ◽

Az31 Alloy ◽

Rolling Process ◽

Alloy Sheet ◽

Microstructure And Mechanical Properties ◽

High Anisotropy ◽

Az31 Sheet ◽

Differential Speed Rolling ◽

Conventional Rolling ◽

Differential Speed

Magnesium alloy AZ31, which processed by conventional rolling or extrusion, has high anisotropy of mechanical properties in its strength and elongation at room temperature. We compared the influence of differential speed rolling with conventional rolling process on microstructure and mechanical properties of commercial AZ31 sheet. Commercial AZ31 alloy sheets were processed with conventional and differential speed rolled with thickness reduction ratio of 30% at a various temperature. The elongation of AZ31 alloy, warm-rolled by differential speed rolling is larger than rolled by conventional rolling. Besides, grain size and distribution on microstructure of the conventional rolling were coarsely(~30μm) and inhomogeneously but, that those of the differential speed rolling were fine(~13μm) and homogeneously.

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Crystallographic Differences of Metastable NI2MO in a NI-MO-AL Superalloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000672 ◽

1980 ◽

Vol 38 ◽

pp. 158-159

Author(s):

Michael M. Kersker ◽

E. A. Aigeltinger ◽

J. J. IIren

Keyword(s):

Mechanical Properties ◽

Air Cooling ◽

Solution Treated ◽

Heat Treated ◽

Metastable Compounds ◽

Rapidly Solidified

Ni-rich alloys based on approximate ternary composition Ni-8Mo-15A1 (at%) are presently under investigation in an attempt to study the contribution, if any, of the profusion of Mo-rich NixMo metastable compounds that these alloys contain to their excellent mechanical properties. One of the alloys containing metastable NixMo precipitates is RSR 197 of composition Ni-8.96Mo-15.06A1-1.98Ta-.015Yt. The alloy was prepared at Pratt and Whitney Government Products Division, West Palm Beach, Florida, from rapidly solidified powder. The powder was canned under inert conditions and extruded as rod at 1315°C. The as-extruded rod, after air cooling, was solution treated at 1315°C for two hours, air cooled, and heat treated for one hour at 815°C, followed again by air cooling.

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A Study on Polymer Particle Flow in a Disk Zone of a Screw-Disk Extruder

Chemical and Process Engineering ◽

10.2478/cpe-2014-0009 ◽

2014 ◽

Vol 35 (1) ◽

pp. 121-135 ◽

Cited By ~ 3

Author(s):

Tomasz Rydzkowski ◽

Iwona Michalska-Pożoga

Keyword(s):

Mechanical Properties ◽

Computer Simulations ◽

Particle Motion ◽

Polymer Melt ◽

Experimental Tests ◽

Polymer Particle ◽

Particle Flow ◽

Material Particle ◽

Motion Trajectories ◽

Stretching Effect

Abstract The paper presents the summary of research on polymer melt particle motion trajectories in a disc zone of a screw-disk extruder. We analysed two models of its structure, different in levels of taken simplifications. The analysis includes computer simulations of material particle flow and results of experimental tests to determine the properties of the resultant extrudate. Analysis of the results shows that the motion of melt in the disk zone of a screw-disk extruder is a superposition of pressure and dragged streams. The observed trajectories of polymer particles and relations of mechanical properties and elongation of the molecular chain proved the presence of a stretching effect on polymer molecular chains.

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