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Title: Computer Simulation of Material Flow in Warm-forming Bimetallic Components

Abstract

Bimetallic components take advantage of two different metals or alloys so that their applicable performance, weight and cost can be optimized. However, since each material has its own flow properties and mechanical behaviour, heterogeneous material flows will occur during the bimetal forming process. Those controls of process parameters are relatively more complicated than forming single metals. Most previous studies in bimetal forming have focused mainly on cold forming, and less relevant information about the warm forming has been provided. Indeed, changes of temperature and heat transfer between two materials are the significant factors which can highly influence the success of the process. Therefore, this paper presents a study of the material flow in warm-forming bimetallic components using finite-element (FE) simulation in order to determine the suitable process parameters for attaining the complete die filling. A watch-case-like component made of stainless steel (AISI-316L) and aluminium alloy (AL-6063) was used as the example. The warm-forming processes were simulated with the punch speeds V of 40, 80, and 120 mm/s and the initial temperatures of the stainless steel TiSS of 625, 675, 725, 775, 825, 875, 925, 975, and 1025 deg. C. The results showed that the AL-6063 flowed faster than the AISI-316Lmore » and so the incomplete die filling was only found in the AISI-316L region. A higher TiSS was recommended to avoid incomplete die filling. The reduction of V is also suggested because this can save the forming energy and prevent the damage of tooling. Eventually, with the experimental verification, the results from the simulation were in agreement with those of the experiments. On the basis of the results of this study, engineers can gain a better understanding of the material flow in warm-forming bimetallic components, and be able to determine more efficiently the punch speed and initial material temperature for the process.« less

Authors:
; ;  [1]
  1. Department of Industrial and System Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)
Publication Date:
OSTI Identifier:
21057326
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 908; Journal Issue: 1; Conference: NUMIFORM '07: 9. international conference on numerical methods in industrial forming processes, Porto (Portugal), 17-21 Jun 2007; Other Information: DOI: 10.1063/1.2740946; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE; ALUMINIUM ALLOYS; BIMETALS; COMPUTERIZED SIMULATION; CONTROL; FINITE ELEMENT METHOD; HEAT TRANSFER; HOT WORKING; METALS; PERFORMANCE; STAINLESS STEELS; TITANIUM SULFIDES; VELOCITY

Citation Formats

Kong, T. F., Chan, L. C., and Lee, T. C. Computer Simulation of Material Flow in Warm-forming Bimetallic Components. United States: N. p., 2007. Web. doi:10.1063/1.2740946.
Kong, T. F., Chan, L. C., & Lee, T. C. Computer Simulation of Material Flow in Warm-forming Bimetallic Components. United States. doi:10.1063/1.2740946.
Kong, T. F., Chan, L. C., and Lee, T. C. Thu . "Computer Simulation of Material Flow in Warm-forming Bimetallic Components". United States. doi:10.1063/1.2740946.
@article{osti_21057326,
title = {Computer Simulation of Material Flow in Warm-forming Bimetallic Components},
author = {Kong, T. F. and Chan, L. C. and Lee, T. C.},
abstractNote = {Bimetallic components take advantage of two different metals or alloys so that their applicable performance, weight and cost can be optimized. However, since each material has its own flow properties and mechanical behaviour, heterogeneous material flows will occur during the bimetal forming process. Those controls of process parameters are relatively more complicated than forming single metals. Most previous studies in bimetal forming have focused mainly on cold forming, and less relevant information about the warm forming has been provided. Indeed, changes of temperature and heat transfer between two materials are the significant factors which can highly influence the success of the process. Therefore, this paper presents a study of the material flow in warm-forming bimetallic components using finite-element (FE) simulation in order to determine the suitable process parameters for attaining the complete die filling. A watch-case-like component made of stainless steel (AISI-316L) and aluminium alloy (AL-6063) was used as the example. The warm-forming processes were simulated with the punch speeds V of 40, 80, and 120 mm/s and the initial temperatures of the stainless steel TiSS of 625, 675, 725, 775, 825, 875, 925, 975, and 1025 deg. C. The results showed that the AL-6063 flowed faster than the AISI-316L and so the incomplete die filling was only found in the AISI-316L region. A higher TiSS was recommended to avoid incomplete die filling. The reduction of V is also suggested because this can save the forming energy and prevent the damage of tooling. Eventually, with the experimental verification, the results from the simulation were in agreement with those of the experiments. On the basis of the results of this study, engineers can gain a better understanding of the material flow in warm-forming bimetallic components, and be able to determine more efficiently the punch speed and initial material temperature for the process.},
doi = {10.1063/1.2740946},
journal = {AIP Conference Proceedings},
number = 1,
volume = 908,
place = {United States},
year = {Thu May 17 00:00:00 EDT 2007},
month = {Thu May 17 00:00:00 EDT 2007}
}
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