New approaches to optimize strain behavior of Al6082 during equal channel angular pressing

Abstract

Equal channel angular pressing is one of the attractive methods of severe plastic deformation techniques to fabricate ultrafine grained materials. In this study, eight different equal channel angular pressing configurations including the punch shape, sample preform and die geometry have been analyzed using finite element method to achieve materials with the high effective strain magnitude, better strain distribution uniformity and less required pressing force. The results show that the combination of punch shape and back slant specimen is the most efficient modification as compared to the conventional equal channel angular pressing process. Furthermore, investigations on various die channel and sample slant angles indicate that the configuration of punch shape and back slant sample with the die channel angle of 75°and sample slant angle of 30°is the optimum condition. Finally, experimental work has been performed to validate the results.

A study on the capability of equal channel forward extrusion process

“…Hollomon's relationship was utilized to characterize the material behavior, in accordance with Eq. (4) in which σ, K, ε and n are effective von-Mises stress, strength coefficient, effective plastic strain and strain hardening exponent, respectively [20]. The values of strength coefficient (K) and strain hardening exponent (n) were obtained via the true stress -strain curve for the as-received billet.…”

Strain Behavior of Nickel Alloy 200 during Multiaxial Forging through Finite Element Modeling

“…It has been reported that external conditions, such as die geometries, processing, and friction, as well as internal conditions, such as work hardening and the strain rate sensitivity of the material, may contribute to inhomogeneity of the processed material [16][17][18][19][20][21]. For example, Ebrahimi et al [21] studied the influence of punch and die geometry on strain distribution of the aluminum alloy processed by ECAP. Inhomogeneity in structure can be assessed by a factor known as the inhomogeneous factor (IF) or coefficient of standard deviation and can be expressed by the following equation [21]:…”

“…For example, Ebrahimi et al [21] studied the influence of punch and die geometry on strain distribution of the aluminum alloy processed by ECAP. Inhomogeneity in structure can be assessed by a factor known as the inhomogeneous factor (IF) or coefficient of standard deviation and can be expressed by the following equation [21]:…”

“…Dissimilar to quasistatic processes, the material response may vary due to thermal and inertial forces. Moreover, lubricating conditions may influence the strain distribution [21]. For example, the brittle materials require high temperature for forging.…”

Uncertainty analysis of residual stresses measured by slitting method in equal-channel angular rolled Al-1060 strips

“…Many scholars have developed varied SPD processes for components with different shapes. 14 Constrained groove pressing (CGP), 15 equal-channel angular pressing (ECAP), 16,17 tube channel pressing (TCP) 18 and repetitive tube expansion and shrinking (RTES) 19 are some of them.…”