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Reduction of Grain Growth for Al6061 Alloy by the Die Cooling System in Hot Extrusion Process

Al6061 합금의 열간 압출공정에서 금형 냉각시스템에 의한 압출재의 결정립 성장 제어

  • Published : 2009.07.01

Abstract

In this study, die cooling system using the nitrogen gas has been applied to hot aluminum extrusion process for refining grains and reducing of grain growth. Computational fluid dynamics(CFD) has been carried out to evaluate die cooling effect by nitrogen gas, and the results of CFD have been used to FE-simulation for the prediction of the extrudate temperature in hot extrusion process. Experimental hot extrusion has been performed to observe microstructure and to measure temperature of extrudate. The results of FE-Simulation have been good agreement with those of experiment. Finally, process condition of hot extrusion can be established to reduce grain growth of Al6061 through the experiment.

Keywords

Microstructure Evolution;Grain Growth;Die Cooling System;Aluminum Hot Extrusion;Computational Fluid Dynamics(CFD);FE-Simulation

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