NUMERICAL SIMULATION OF OUTER DIE ANGLE OF EQUAL CHANNEL ANGULAR EXTRUSION PROCESS

摘要

The study of the simulation of effect of outer die angle in Equal Channel AngularudExtrusion (ECAE) process was investigated. The simulation was carried out on 6063udaluminium alloy with a view to achieve ultra-fine grain structures. ADINA userudinterphase Version 8.6 (900 modes) was used for the simulation. The unextrudedudparameters of the 6063 aluminium alloy were used as input codes and some basicudassumptions were made in designing the model on 2-Dimensional scale. The billet wasudmeshed by dividing the vertical and horizontal geometry into 30 and 4 elementsudrespectively. The die angle was varied from 0oud to 90oud and the simulation results wereuddisplayed. The results showed that the force of 27.5X106 N, 27.5X106 N, 27.6X106 Nudand 31.2 X106 N was required to deform when the outer die angle was 0oud, 22.5oud, 45oudand 90oud respectively. Also, the strains achieved were 0.61, 0.62, 0.66 and 0.69udrespectively. Thus, highest force is required at 90oud and the strain achieved at 0oud is theudlowest. Based on the results, it was recommended that it is more economical toudextrude at an outer angle between 22.5oud and 45oud as a relatively higher effective strainudwill be induced.