Upper Bound Analysis of the ECAE Process by Considering Strain Hardening Materials and Three-Dimensional Rectangular Dies

2008 ◽  
Vol 130 (5) ◽  
Author(s):  
R. Luri ◽  
C. J. Luis Pérez
Keyword(s):  
Strain Hardening ◽  
Cross Section ◽  
Upper Bound ◽  
Equal Channel Angular Extrusion ◽  
Rectangular Cross Section ◽  
Three Dimensional ◽  
Plastic Deformations ◽  
Material Parameters ◽  
Upper Bound Analysis ◽  
Bound Analysis

Equal channel angular extrusion (ECAE) or pressing is a process used to introduce severe plastic deformations to processed materials with the aim of improving their mechanical properties by reducing the grain size. At present, there are no analytical studies that have considered strain hardening materials in order to determine the required force to carry out the process. All the existing papers have only considered nonstrain hardening materials. Furthermore, all those studies have been done by considering plane strain conditions. In this work, an upper bound analysis of the required force for performing the ECAE process is made by considering a full three-dimensional geometry with a rectangular cross section. From this analysis, the influence of the geometric and the material parameters is studied by considering both friction and strain hardening materials. By using the upper bound method, an analytical formulation was obtained and the influence of all the parameters was determined. With this work, it is possible to have a wider knowledge of the influence of the main affecting parameters in the ECAE process and to optimize them.

Upper Bound Analysis of the ECAE Process by Considering Circular Cross-Section and Strain Hardening Materials

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
C. J. Luis Pérez ◽  
R. Luri
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Strain Hardening ◽  
Cross Section ◽  
Upper Bound ◽  
Equal Channel Angular Extrusion ◽  
Circular Cross Section ◽  
Experimental Tests ◽  
Extrusion Force ◽  
Deformation Processes

Severe plastic deformation processes have a great deal of importance because of the improvement in mechanical properties of the processed parts as a consequence of the grain size reduction in the material due to the accumulation of deformation. One of the main severe plastic deformation (SPD) processes is called the equal channel angular extrusion (ECAE). Although a large amount of studies, which deal with experimental analysis of processed parts exist, few studies dealing with the force required to perform the process have been developed. In this study, an analytical modeling of the force required to perform the ECAE process has been developed using the upper bound method (UBM). The analytical equations developed take into account the material strain hardening and the ECAE dies with circular cross-section. Moreover, the experimental tests have been performed and the extrusion force has been measured. The UBM and experimental results have been compared showing a great deal of agreement.

Sign in / Sign up

Export Citation Format

Share Document