Effect of Equal-Channel Angular Pressing and Second Phase on Pitting Corrosion of Ultrafine-Grained Steel

In this study, equal channel angular pressing was carried out on Cu-Fe-Cr composites at room temperature. The microstructure and hardness of Cu-Fe-Cr pressed using different ECAP routes were investigated. All Cu-Fe-Cr specimens showed ultrafine-grained microstructures with the shape and distribution of Fe-Cr phase dependent on the processing routes. As the number of pressing increased by route A, the initial denfrite of Fe-Cr phase were elongated along the shear direction and developed into filaments. On the other hand, as the number of pressing increased by route Bc, the initial dendrite became finer by fragmentation with no pronounced change of the shape. In route C, the shearing of the second phase in the first pass can be reversed by the shearing in the reverse direction in the second pass and the morphological change of Fe-cr particles is minimal. The hardness increased more rapidly in route Bc and route C than in route A. In ECAPed Cu-Fe-Cr, the spacing between Fe-Cr filaments did not decrease appreciably with strain unlike the cold-drawn Cu-Fe-Cr in which the spacing between Fe-Cr filaments decreases rapidly with strain. The higher strength in route C can be associated with the sub-divided microstructure resulting from the activation of various slip systems enhanced by the presence of larger strong particles. This result suggests that the microstructural development in Cu matrix is more important in strengthening than the morphological development of Fe-Cr phase in ECAPed Cu-Fe-Cr.

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Production of Bulk Ultrafine Grained Steel through Severe Plastic Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.583 ◽

2010 ◽

Vol 667-669 ◽

pp. 583-588

Author(s):

Mehdi Shaban Ghazani ◽

Beitallah Eghbali

Keyword(s):

Equal Channel Angular Pressing ◽

Dynamic Strain ◽

Final Size ◽

Continuous Dynamic Recrystallization ◽

Forward Extrusion ◽

Angular Pressing ◽

Element Simulation ◽

Ultrafine Grained ◽

Continuous Dynamic ◽

Ultrafine Grained Steel

In the present research, a combined forward extrusion-equal channel angular pressing (FE-ECAP) was developed and used for production of bulk ultrafine grained steel in the high temperature conditions. In this method, two different deformation steps including forward extrusion and equal channel angular pressing takes place successively in a single die. The deformation process was performed at different deformation start temperatures (800, 930, and 1100 °C). In addition, 3D finite element simulation was used to predict the hot/warm deformation parameters such as strain and temperature variations within the samples during deformation. The results show that the EF-ECAP process is effective in refining the grains from initial size of 32 m to final size of 0.9 m after executing of extrusion and ECAP on as received samples. The main mechanisms of grain refinement were considered to be strain assisted transformation, dynamic strain-induced transformation, and continuous dynamic recrystallization.

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Structural heterogeneity of ultrafine-grained FCC metals processed through equal-channel angular pressing on mesoscale level

10.1063/1.5132007 ◽

2019 ◽

Author(s):

K. V. Ivanov

Keyword(s):

Equal Channel Angular Pressing ◽

Structural Heterogeneity ◽

Fcc Metals ◽

Angular Pressing ◽

Ultrafine Grained

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Superplastic Behavior in Ultrafine-Grained Materials Produced by Equal-Channel Angular Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.579.29 ◽

2008 ◽

Vol 579 ◽

pp. 29-40 ◽

Cited By ~ 3

Author(s):

Cheng Xu ◽

Megumi Kawasaki ◽

Roberto B. Figueiredo ◽

Zhi Chao Duan ◽

Terence G. Langdon

Keyword(s):

Equal Channel Angular Pressing ◽

High Strain ◽

Processing Method ◽

Strain Rates ◽

Bulk Materials ◽

Superplastic Behavior ◽

Angular Pressing ◽

Ultrafine Grained ◽

Ultrafine Grained Materials ◽

Aluminum And Magnesium Alloys

Equal-channel angular pressing (ECAP) is a convenient processing method for refining the grain size of bulk materials to the submicrometer level. Metallic alloys processed by ECAP often exhibit excellent superplastic characteristics including superplasticity at high strain rates. This paper summarizes recent experiments designed to evaluate the occurrence of superplasticity in representative aluminum and magnesium alloys and in the Zn-22% Al eutectoid alloy.

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Enhanced Impact Toughness at Ambient Temperatures of Ultrafine-Grained Al-26 wt.% Si Alloy Produced by Equal-Channel Angular Pressing

Journal of Materials Engineering and Performance ◽

10.1007/s11665-018-3283-0 ◽

2018 ◽

Vol 27 (5) ◽

pp. 2131-2137 ◽

Cited By ~ 2

Author(s):

Jinghua Jiang ◽

Ting Yuan ◽

Jun Shi ◽

Lingling Zhang ◽

Aibin Ma ◽

...

Keyword(s):

Impact Toughness ◽

Equal Channel Angular Pressing ◽

Ambient Temperatures ◽

Angular Pressing ◽

Ultrafine Grained

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Effect of Equal Channel Angular Pressing and Annealing on Corrosion Resistance of Al-Cu Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.803.226 ◽

2013 ◽

Vol 803 ◽

pp. 226-229

Author(s):

Da Ran Fang ◽

Chun Liu ◽

Feng Fang Liu

Keyword(s):

Corrosion Resistance ◽

Low Temperature ◽

Equal Channel Angular Pressing ◽

Annealing Treatment ◽

Coarse Grained ◽

Nacl Solution ◽

Angular Pressing ◽

Cu Alloy ◽

Low Temperature Annealing ◽

Ultrafine Grained

Al-3.9wt.%Cu alloy was subjected to equal channel angular pressing (ECAP) and subsequent low temperature annealing treatment, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion rate of the ultrafine-grained alloy increases, in comparison with the coarse-grained alloy. Meanwhile, it is noted that the corrosion resistance of the alloy subjected to ECAP can be improved by relief annealing.

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