Failure Prediction during uniaxial Superplastic Tension using Finite Element Method

Document Type: Research Paper

Authors

Babol Noshirvani University of Technology

Abstract

Superplastic materials show a very high ductility. This is due to both peculiar process conditions and material intrinsic characteristics. However, a number of superplastic materials are subjected to cavitation during superplastic deformation. Evidently, extensive cavitation imposes significant limitations on their commercial application. The deformation and failure of superplastic sheet metals are a result of a combination and interaction process between tensile instability and internal cavity evolution. Thus, this study carried out modeling of the uniaxial superplastic tensile test using a code based on the finite element method, that used a microstructure based constitutive model and a deformation instability criterion. These models are the criterion account for both geometrical instabilities and cavitation. It is observed that the proposed approach captures the characteristics of deformation and failure during superplastic forming. In addition, the effects of the cavitation on the superplastic forming process were investigated. The results clearly indicated the importance of accounting for these features to prevent premature failure.

Keywords


[1] J. Pilling, N. Ridley, Superplasticity in Crystalline Solids, The Institute of Metals, 1989.

[2] C. H. Hamilton, A. K. Ghosh, Superplastic sheet forming, in: ASM Handbook, Vol. 14B, 2006.

[3] Y. H. Kim, S. S. Hong, J. S. Lee, R. H. Wagoner, Analysis of superplastic forming processes using a finite-element method, Journal of Materials Processing Technology, 62 (1996) 90–99.

[4] L. Carrino, G. Giuliano, C. Palmieri, Analysis of superplastic bulge forming by the finite element method, Journal of Materials Processing Technology, 16 (2001) 237–241.

[5] L. Carrino, G. Giuliano, W. Polini, A method to characterise superplastic materials in comparison with alternative methods, Journal of Materials Processing Technology, 138 (2003) 417–422.

[6] F. Shehata, M. J. Painter, R. Pearce, Warm forming of aluminum/magnesium alloy sheet, Journal of Mechanical Working Technology, 2 (1978) 279–290.

[7] T. Naka, G. Torikai, R. Hino, The effect of temperature and forming speed on the forming limit diagram for type 5083 aluminum-magnesium alloy sheet, Journal of Materials Processing Technology, 113 (2001) 648-653.

[8] S. J. Hosseinipour, An investigation into hot deformation of aluminum alloy 5083, Materials and Design, 30 (2009) 319–322.

[9] S. J. Hosseinipour, Strain rate sensitivity and cavitation in superplastic deformation of a commercial Al-5083 alloy, Advanced Materials Research, 83-86 (2010) 400-406.

[10] L. C. Chung, J. H. Cheng, Fracture criterion and forming pressure design for superplastic bulging, Materials Science Engineering A, 33 (2002) 146-151.

[11] R. Pearce, Superplasticity – an overview. Ashford Press, Curdridge, Southampton, Hampshire, 1989.

[12] Z. Marciniak, K. Kuczynski, Limit strain in the processes of stretch-forming sheet metals, International Journal of Mechanical Science, 9 (1967) 609.

[13] M. J. Stowell, Superplastic forming of structural alloys, In: Paton NE, Hamilton CH, editors. Warrendale: TMS-AIME, (1982) 321 –336.

[14] G. Giuliano, S. Franchitti, The determination of material parameters from superplastic free-bulging tests at constant pressure, International Journal of Machine Tools and Manufacturing, 48 (2008) 1519– 1522.

[15] D. Sorgente, L. D. Scintilla, Blow forming of AZ31 magnesium alloy at elevated temperatures, International Journal of Materials Forming, 3 (2010) 13–19.

[16] j. Liu, Z. Chen, H. Yan, Many-stage gas bulging forming of sheet magnesium alloy AZ31, Metal Science and Heat Treatment, 50 (2008) 110-114.

[17] M. Koç, E. Billur, An experimental study on the comparative assessment of hydraulic bulge test analysis methods, Materials and Design, 32 (2011) 272–281.

[18]. ABAQUS V.6.9 Documentation, Abaqus User Subroutines Reference Manual, section 1.1.17.