4. Conclusions
• The wiredrawing force and the friction coefficient values decrease while the velocity increases.
• The die with 2β = 10º presents wiredrawing force up to 23.2% lower and friction coefficient up to 60.5% lower than those for a die with 2β = 18º, considering Hc = 35% and Hc = 50%.
• In dies with 2β = 10º, the wiredrawing force result is 4.4% lower and the friction coefficient value is 1.5% lower for Hc = 35% than those obtained with dies with Hc = 50%.
• The Finite Element Method was applied in the simulation of wire drawing process to predict the distribution of residual stresses in drawn wires. The reduction zone (II) presents maximum radial stress on the surface and on the intermediate region, while the maximum axial stress is on the surface. Such behavior is more intense for 2β = 18º than for 2β = 10º.
• The residual stress is permanent and thus determines important influence on fatigue properties, among other mechanical properties, after the wiredrawing process is completed. The total results of simulation show tensile axial stress applied on the surface of the wire, compression stress in the intermediate region, and intense residual stress level for 2β = 18º, showing the influence of stress on reduction zones.
Acknowledgements
Our appreciation to MSC Software of Brazil for providing PATRAN 2003 r3 and MARC 2001 software, and to FAPESP (Grants º 15966-6 and 02/00834-4)