Atomic-scale structural evolution in amorphous Nd9Fe85B6 subjected to severe plastic deformation at room temperature

2009 ◽  
Vol 94 (23) ◽  
pp. 231904 ◽  
Author(s):  
Wei Li ◽  
Xiaohong Li ◽  
Defeng Guo ◽  
Kiminori Sato ◽  
Dmitry V. Gunderov ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Room Temperature ◽  
Structural Evolution ◽  
Atomic Scale

scholarly journals Aging Behaviour of Al-Mg-Si Alloys Subjected to Severe Plastic Deformation by ECAP and Cold Asymmetric Rolling

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
S. Farè ◽  
N. Lecis ◽  
M. Vedani
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Isothermal Aging ◽  
Room Temperature ◽  
Coarse Grained ◽  
Peak Shape ◽  
Asymmetric Rolling ◽  
Ultrafine Grained ◽  
Aging Kinetics ◽  
Reduced Intensity

A study was carried out on aging behaviour of a 6082 alloy processed by two different severe plastic deformation techniques: ECAP and asymmetric rolling. Both techniques were able to generate an ultrafine-grained structure in samples processed at room temperature. It was stated that severe straining promotes marked changes in the postdeformation aging kinetics. The peaks of β′′/β′ transition phases were anticipated and of progressively reduced intensity over the coarse grained alloy. A further peak accounting for onset of recrystallization also appeared in the most severely deformed samples. Full consistency in peak shape and position was found when comparing materials processed by ECAP and asymmetric rolling. Isothermal aging treatments performed at 180°C revealed that in the severely deformed samples, aging became so fast that the hardness curves continuously decreased due to overwhelming effects of structure restoration. On the contrary, aging at 130°C offers good opportunities for fully exploiting the precipitate hardening effects in the ultrafine-grained alloy.

Superplasticity of Aerospace 7075 (Al-Zn-Mg-Cu) Aluminium Alloy Obtained by Severe Plastic Deformation

2018 ◽  
Vol 385 ◽  
pp. 39-44 ◽  
Author(s):  
Fernando Carreño ◽  
Oscar A. Ruano
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Aluminium Alloy ◽  
Room Temperature ◽  
Grain Boundary Sliding ◽  
Strain Rates ◽  
Aerospace Applications ◽  
Boundary Sliding ◽  
Processing Stress

The 7075 (Al-Zn-Mg-Cu) aluminium alloy is the reference alloy for aerospace applications due to its specific mechanical properties at room temperature, showing excellent tensile strength and sufficient ductility. Formability at high temperature can be improved by obtaining superplasticity as a result of fine, equiaxed and highly misoriented grains prone to deform by grain boundary sliding (GBS). Different severe plastic deformation (SPD) processing routes such as ECAP, ARB, HPT and FSP have been considered and their effect on mechanical properties, especially at intermediate to high temperatures, are studied. Refined grains as fine as 100 nm and average misorientations as high as 39o allow attainment of high strain rate superplasticity (HSRSP) at lower than usual temperatures (250-300oC). It is shown that increasing misorientations are obtained with increasing applied strain, and increasing grain refinement is obtained with increasing processing stress. Thus, increasing superplastic strains at higher strain rates, lower stresses and lower temperatures are obtained with increasing processing strain and, specially, processing stress.

Current States and Development of Research on Redissolution and Reprecipitation of Nanoprecipitated Phases in Al–Cu Alloys

2019 ◽  
Vol 11 (11) ◽  
pp. 1489-1501
Author(s):  
Wenjing He ◽  
Caihe Fan ◽  
Shu Wang ◽  
Junhong Wang ◽  
Su Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Room Temperature ◽  
Supersaturated Solid Solution ◽  
Aluminum Matrix ◽  
Aging Treatment ◽  
Cu Alloys ◽  
The Reformation

The evolution of nanoprecipitated phases in Al–Cu alloys under severe plastic deformation (SPD) is summarized in this study. SPD at room temperature induces the precipitation of Al–Cu alloys to dissolve, leading to the reformation of supersaturated solid solution in the aluminum matrix. In the process of SPD or aging treatment after the SPD, the reprecipitated phases are precipitated from the aluminum matrix and the mechanical properties of the alloys are remarkably improved. The mechanism and system of the redissolution of the precipitation phases and the effects of redissolution and reprecipitation on the microstructure and properties of Al–Cu alloys are comprehensively analyzed. The development and future of redissolution and reprecipitation of nanoprecipitated phases in Al–Cu alloys are also described.

Plastic flow anisotropy of pure zirconium after severe plastic deformation at room temperature

2009 ◽  
Vol 57 (16) ◽  
pp. 4855-4865 ◽  
Author(s):  
G.G. Yapici ◽  
C.N. Tomé ◽  
I.J. Beyerlein ◽  
I. Karaman ◽  
S.C. Vogel ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Plastic Flow ◽  
Room Temperature ◽  
Pure Zirconium ◽  
Flow Anisotropy

Upgrading Property of A-Fe Alloys through the Microstructure Refinement by Compressive Torsion Processing

2014 ◽  
Vol 794-796 ◽  
pp. 802-806 ◽  
Author(s):  
Yuji Kume ◽  
Shinichiro Ota ◽  
Makoto Kobashi ◽  
Naoyuki Kanetake
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Tensile Properties ◽  
Grain Refinement ◽  
Deformation Process ◽  
Room Temperature ◽  
Plastic Deformation Process ◽  
Deformation Processes ◽  
Alloy Microstructure ◽  
Fe Alloys

Cast AlFe alloys containing several percent iron have low ductility because of their brittle precipitates. Therefore, precipitate refinement is very important for improving their mechanical properties. In recent decades, severe plastic deformation processes have been developed to achieve this grain refinement. For example, our previously proposed severe plastic deformation process, called compressive torsion, is quite effective for not only grain refinement but also precipitate refinement even in brittle materials. In the present work, precipitate refinement of cast Al—Fe alloys by compressive torsion and the resulting improvements in their tensile properties were investigated. Compressive torsion with various numbers of revolutions was applied to Al—Fe alloys at 373 K. Then, the alloys were subjected to tensile testing at room temperature, 473 K, and 573 K. The obtained experimental results indicated that the initial eutectic microstructure of the alloys disappeared after the compressive torsion processing. All large precipitates with sizes of more than 200 μm were refined, and their sizes were reduced to several tens of micrometers. Furthermore, these refined precipitates were dispersed homogenously in the alloy microstructure. In result, the tensile properties of the alloys, namely, their strength and elongation, were improved remarkably. In particular, the elongation reached more than 30% at room temperature.

Characterizing the Shear Deformation during Asymmetric Rolling

2008 ◽  
Vol 584-586 ◽  
pp. 327-332 ◽  
Author(s):  
Yun Long Chen ◽  
Ai Dang Shan ◽  
Jian Hua Jiang ◽  
Yi Ding
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Shear Deformation ◽  
Room Temperature ◽  
Pure Aluminum ◽  
Asymmetric Rolling ◽  
Metallic Material ◽  
Side Face ◽  
High Reduction ◽  
Very High

Asymmetric rolling has been considered as a possible way to obtain severe plastic deformation (SPD) since it will give an extra shear deformation to the processed materials during rolling. Previous researches have confirmed such a shear deformation. Very recently, the method of inserting-block is used to characterize the shear deformation through direct observation, but when the reduction is more than 70%, the lineation scratched on the side face of internal mark becomes vague and illegible. In order to directly observe the shear deformation of metallic material with large reduction, the internal mark method is employed in this research and asymmetric rolling was performed with pure aluminum and iron at room temperature. In severe plastic deformation, the shear deformation caused by asymmetric rolling was clearly observed and measured through employing internal mark method. Remarkable extra shear deformation during asymmetric rolling was confirmed. Very high equivalent strains were achieved when sheet samples were asymmetrically rolled to high reduction ratio. These strain values fall into the range of SPD.

Effect of Severe Plastic Deformation by Torsion on Structure and Properties of Ni54Mn21Ga25 and Ni54Mn20Fe1Ga25

2010 ◽  
Vol 168-169 ◽  
pp. 553-556
Author(s):  
N.I. Kourov ◽  
Vladimir Pushin ◽  
A.V. Korolev ◽  
V. Marchenkov ◽  
E. Marchenkova ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Physical Properties ◽  
Room Temperature ◽  
Martensitic Transformations ◽  
Martensitic Transition ◽  
Magnetic Shape Memory ◽  
Bridgman Anvil ◽  
Disordered Alloys ◽  
Cast Alloys

We report on the effect of severe plastic deformation by torsion under the Bridgman anvil pressure (SPDT) on structure and physical properties of the Ni54Mn21Ga25 and Ni54Mn20Fe1Ga25 alloys. Two types of samples were studied: ordered (cast) samples and nanocrystalline samples disordered by SPDT. The thermal expansion, thermo EMF, electro- and magnetoresistivity, Hall effect, and magnetization were measured from 4.2 to 800 K and in magnetic fields of up to 15T. We show that the deviation from the stoichiometric Ni50Mn25Ga25 composition shifts the temperatures of the martensitic transition TM and the magnetic (Curie) transition TC to room temperature. Large changes in the physical properties near TM and TC were discovered. The alloys become amorphous and nanocrystalline after the SPDT treatment. This process is accompanied by the disappearance of the martensitic transformations and of the nanocrystalline modulated substructures and, consequently, by the suppression of the magnetic shape-memory effect. The physical properties of the disordered alloys are also strongly changed. Subsequent annealing at Т ≥ 700 K leads to a practically full restoration of the structure and all properties characteristic of the initial cast alloys.

Mechanical Properties and Microstructural Behavior of a Metal Matrix Composite Processed by Severe Plastic Deformation Techniques

MRS Advances ◽  
2015 ◽  
Vol 1 (58) ◽  
pp. 3865-3870 ◽  
Author(s):  
Shima Sabbaghianrad ◽  
Terence G. Langdon
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Metal Matrix ◽  
Room Temperature ◽  
High Pressure Torsion ◽  
Average Grain Size ◽  
Al 7075 ◽  
7075 Alloy

ABSTRACTA severe plastic deformation (SPD) technique was applied to an Al-7075 alloy reinforced with 10 vol.% Al2O3. This processing method of high-pressure torsion (HPT) was performed at room temperature under a pressure of 6.0 GPa through a total number of up to 20 turns. The metal matrix composite (MMC) showed a significant grain refinement from an initial average grain size of ∼8 μm to ∼300 nm after processing by HPT through 20 turns which led to an increase in the average values of Vickers microhardness at room temperature.

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