Application of Ductile Damage Concepts in the Evaluation of Material Formability during Screw Head Cold Forming

Abstract:

An up to date approach to material cold formability, based on a conventional J₂ theory for plasticity together an uncoupled linear plastic damage evolution theory, is applied to the study of steel bolt head cold forming. Specific laboratory tests to characterize the material formability have been used. Finite element simulations have been performed to characterize the strain and stress state both in the forming process and in experimental tests to determine the material ductile fracture locus. The influence of chemical composition and initial microstructure is discussed.

• Periodical: Key Engineering Materials (Volumes 577-578)
• Pages: 249-252
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.577-578.249
• Online since: September 2013
• Authors: Tommaso Coppola, L. Cortese, Claudio Guarnaschelli, I. Salvatori
• Keywords: Formability, Lode Angle, Plastic Damage, Triaxiality

References

[1] Coppola T., Cortese L., Folgarait P.: Eng. Frac. Mech. 76 (2009), pp.1288-1302.

[2] Coppola T., Demofonti G., Mannucci G.:XIX ISOPE Conference, Strain-based Design Symposium, Vol. IV, TPC 761, Osaka, 2009.

[3] ASM Handbook, Forming and forging, Vol. 14, 1993, ASM International.