The evolution of damage in perfect-plastic and strain hardening materials processed by equal-channel angular pressing

2009 ◽  
Vol 518 (1-2) ◽  
pp. 124-131 ◽  
Author(s):  
Roberto B. Figueiredo ◽  
Paulo R. Cetlin ◽  
Terence G. Langdon
Keyword(s):  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
Angular Pressing ◽  
Perfect Plastic

Large strain hardening in Ti–V carbon steel processed by equal channel angular pressing

2001 ◽  
Vol 51 (2) ◽  
pp. 177-182 ◽  
Author(s):  
W.J Kim ◽  
J.K Kim ◽  
W.Y Choo ◽  
S.I Hong ◽  
J.D Lee
Keyword(s):  
Carbon Steel ◽  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
Large Strain ◽  
Angular Pressing

Ultrafine Grained Dual Phase Steels Fabricated by Equal Channel Angular Pressing

2006 ◽  
Vol 503-504 ◽  
pp. 447-454 ◽  
Author(s):  
Dong Hyuk Shin ◽  
Woo Gyeom Kim ◽  
Jung Yong Ahn ◽  
Kyung Tae Park ◽  
Yong Suk Kim
Keyword(s):  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
Room Temperature ◽  
Intercritical Annealing ◽  
Total Elongation ◽  
Coarse Grained ◽  
Dual Phase ◽  
Dual Phase Steels ◽  
Angular Pressing ◽  
Ultrafine Grained

Ultrafine grained (UFG) ferrite-martensite dual phase steels were fabricated by equal channel angular pressing and subsequent intercritical annealing. Their room temperature tensile properties were examined and compared to those of coarse grained counterpart. The formation of UFG martensite islands of ~ 1 μm was not confined to the former pearlite colonies but they were uniformly distributed throughout UFG matrix. The strength of UFG dual phase steels was much higher than that of coarse grained counterpart but uniform and total elongation were not degraded. More importantly, unlike most UFG metals showing negligible strain hardening, the present UFG dual phase steels exhibited extensive rapid strain hardening.

Effects of strain hardenability and strain-rate sensitivity on the plastic flow and deformation homogeneity during equal channel angular pressing

2001 ◽  
Vol 16 (3) ◽  
pp. 856-864 ◽  
Author(s):  
Hyoung Seop Kim ◽  
Sun Ig Hong ◽  
Min Hong Seo
Keyword(s):  
Strain Rate ◽  
Strain Hardening ◽  
Plastic Flow ◽  
Equal Channel Angular Pressing ◽  
Strain Rate Sensitivity ◽  
Rate Sensitivity ◽  
Strain Hardening Exponent ◽  
Angular Pressing ◽  
Deformation Inhomogeneity ◽  
Method Analysis

The effects of strain hardenability and strain rate sensitivity on the plastic flow and deformation inhomogeneity during equal channel angular pressing were studied using a finite element method analysis. In this study, perfect plastic nonhardening and rate-insensitive materials, and rate-sensitive materials were considered. In case of the nonhardening and rate-insensitive materials, the deformed geometry was predicted to be quite uniform and homogeneous. Deformation inhomogeneity developed, however, in materials with finite work-hardening exponent and strain-rate sensitivity. The corner gap formed in strain-hardening materials whereas the upper and lower channel gaps formed in strain-rate-sensitive materials. The deformation inhomogeneity was strongly dependent on the relative effects of strain-hardening exponent and strain-rate sensitivity. The predictions on the deformation inhomogeneity and the formation of corner and channel gaps were compatible with the experimental data published in the literature.

Strategy for Achieving High Strength in Al-Mg-Sc Alloys by Intense Plastic Straining

2012 ◽  
Vol 706-709 ◽  
pp. 55-60 ◽  
Author(s):  
Rustam Kaibyshev ◽  
Anna Mogucheva ◽  
Andrii Dubyna
Keyword(s):  
Grain Size ◽  
Strain Hardening ◽  
Grain Refinement ◽  
Equal Channel Angular Pressing ◽  
High Strength ◽  
Necessary Condition ◽  
Angular Pressing ◽  
Strength Increment ◽  
Hardened Condition

It is shown that implementation of high strains through equal-channel angular pressing (ECAP) and/or rolling into alloys belonging to Al-Mg-Sc-Zr system allows achieving high strength and satisfactory ductility. It was shown that strain hardening gives a main contribution to overall strength increment attributed to intense plastic straining; the role of grain size hardening is minor. However, extensive grain refinement is a necessary condition for retaining sufficient ductility in full-hardened condition for these materials.

Flow Behaviour of Commercial Purity Titanium Subjected to Equal Channel Angular Pressing

2010 ◽  
Vol 667-669 ◽  
pp. 867-872 ◽  
Author(s):  
G.V. Preetham Kumar ◽  
Chakkingal Uday
Keyword(s):  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
Strain Path ◽  
Flow Behavior ◽  
Flow Behaviour ◽  
Commercial Purity ◽  
Direction Parallel ◽  
Initial Flow ◽  
Angular Pressing ◽  
Strain Path Change

Commercial purity Ti was subjected to equal channel angular pressing (ECAP) for up to three passes at 400oC using a die with die angle of 120o. Compression testing of the ECAP specimens was carried out to determine the subsequent flow behavior. Two types of compression test specimen orientations, one parallel to the axis of ECAP and the other at 45o to the axis of the ECAP, were prepared from the specimens subjected to ECAP. Anisotropy in flow behaviour (as indicated by values of strength co-efficient, K and strain hardening exponent, n) was observed. The strain hardening rates were also calculated from the experimentally determined flow curves for the specimens tested in compression in the two orientations. The results have been interpreted in terms of the strain path change parameter between the two deformation steps (ECAP and compression). Strain hardening behaviour and microstructure evolution is discussed in terms of strain path change parameter. Specimens compressed in the direction parallel to the ECAP direction had lower strain hardening exponents while exhibiting higher initial flow stresses. The strain hardening rates were lower for specimens compressed at 45o to the ECAP direction compared to specimens compressed parallel to the ECAP direction.

scholarly journals Strain‐Hardening Behavior in an AA6060‐T6 Alloy Processed by Equal Channel Angular Pressing

2020 ◽  
pp. 2000730
Author(s):  
Tarek Khelfa ◽  
Jairo-Alberto Muñoz-Bolaños ◽  
Fuguo Li ◽  
José-María Cabrera-Marrero ◽  
Mohamed Khitouni
Keyword(s):  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
Hardening Behavior ◽  
Angular Pressing ◽  
Strain Hardening Behavior

Numerical Analysis of Nano- or Micro-Crystalline Materials during ECAP by Dislocation Evolution Method

2007 ◽  
Vol 546-549 ◽  
pp. 687-690
Author(s):  
Shao Rui Zhang ◽  
Qun Feng Chang ◽  
Da Yong Li ◽  
Ying Hong Peng
Keyword(s):  
Strain Hardening ◽  
Equal Channel Angular Pressing ◽  
High Yield ◽  
Pressing Method ◽  
Crystalline Materials ◽  
Angular Pressing ◽  
Fine Grain ◽  
Shear Area ◽  
Analytical Approaches ◽  
Strain Increase

By the severe plastic deformation, the equal channel angular pressing method (ECAP) has been used for producing metal materials with the ultra-fine grain size and specific mechanical properties, in particular high yield strength. Analytical approaches have also been studied by few researchers. However, none of the previous analyses have taken into account the strain hardening of the material by considering the microstructure evolution. In this paper, the deformation behavior and the strain harden of aluminum during equal channel angular pressing was calculated on the basis of a dislocation evolution model. Then simulated stress, strain and strain distribution and strain hardening were analyzed. The strain is seen to rapidly increase when the material passes the shear area. This makes a maximum value of stress. And for the congregation of dislocation density, the maximal value of strain increase with the process continuing.

Sign in / Sign up

Export Citation Format

Share Document