Civil Engineering Reference
In-Depth Information
profile for EAF of sheet metals in uniaxial tension. The model does not utilize
experimental results for prediction of the material flow stress, and this model also
incorporates thermal expansion effects. The model results show very good agree-
ment with experimental testing, and analysis of the flow stress reduction during
current application is approximately 60, 30, and 10 % for bulk thermal softening,
thermal expansion, and the electroplastic effect, respectively.
6.4 Tensile Electroforming Model Conclusions
This chapter covered the modeling of tensile forming for sheet metals subject to
an applied electrical current field. As this process is coupled from a thermal and
mechanical standpoint, the modeling approach considered these two areas individ-
ually and then combined the individual models into a thermo-mechanical model.
Both the individual models were capable of predicting the desired response of
the material in uniaxial tension. The introduced thermo-mechanical model which
also included thermal expansion effects was able to predict the local material
strain, flow stress, and thermal profile for sheet metal in uniaxial tension during
EAF. Analysis of the flow stress reduction during current application showed that
approximately 60 % of the reduction is from bulk thermal softening, 30 % is from
thermal expansion, and 10 % is due to the electroplastic effect. Last, the mechani-
cal experimental testing displayed various current application methods and tech-
niques for utilizing EAF in sheet metal forming.
References
1. ASTM B557M—10 (2010) Standard test methods for tension testing wrought and cast alu-
minum- and magnesium-alloy products (metric)
2. United States Department of Defense (1998) Department of defense handbook: metallic mate-
rials and elements for aerospace vehicle structures, MIL-HDBK-5H
3. Cengel YA (2007) Heat and mass transfer: a practical approach, 3rd edn. McGraw Hill, Boston
4. Jones JJ, Mears L (2013) Thermal response modeling of sheet metals in uniaxial tension dur-
ing electrically-assisted forming. J Manuf Sci Eng 132:021011-1-021011-11
5. Salandro WA, Jones JJ, McNeal TA, Roth JT, Hong ST, Smith MT (2009) Formability
of Al 5xxx sheet metals using pulsed current for varying heat treatments. J Manuf Sci Eng
132:051016-1-051016-11
6. Salandro WA, Khalifa A, Roth JT (2009) Tensile formability enhancement of magnesium
AZ31B-O alloy using electrical pulsing. Trans North Am Manuf Res Inst SME 37:387-394
7. Chapra SC, Canale RP (2006) Numerical methods for engineers, 5th edn. McGraw Hill,
Boston
8. International Magnesium Association (1998) McLean, VA, and MIL-HDBK-5H, 1 Dec 1998,
pp 4-11
