Implementation of Yld96 anisotropy plasticity theory for estimation of polar effective plastic strain based failure limit of pre-strained thin steels. (May 2018)

• Record Type: Journal Article
• Authors: Basak, Shamik; Panda, Sushanta Kumar
• Is Part Of: Thin-walled structures. Volume 126(2018)
• Page Start: 26
• Page End: 37
• Publication Date: 2018-05
• Subjects: EDD thin steels -- Pre-straining -- Yld96 plasticity theory -- Forming limit diagram -- PEPS-FLD -- Limiting dome height; Thin-walled structures -- Periodicals; 690.1
• DOI: 10.1016/j.tws.2017.04.015
• Languages: English
• ISSNs: 0263-8231

Abstract

Abstract: In present work, tensile and stack compression tests were performed along different orientations to evaluate the yield behaviour and strength directionalities of several equi-biaxial, plane strain and uniaxial pre-strained extra deep drawing (EDD) thin steel sheets. Strain based forming limit diagrams (ε-FLD) were evaluated by deforming along six different paths with strain ratio ranging from 0.91 to −0.34, and the dynamic shift of failure strains was established with the cusp moved equal to the amount and direction of minor strain component of the pre-strained materials. Hence, polar effective plastic strain based FLD (PEPS-FLD) was estimated using the Yld96 anisotropy plasticity theory to restrict the dynamic shift of failure strains irrespective of the amount and type of pre-strain. Unlike ε-FLD, the consideration of PEPS-FLD along with Yld96 anisotropy coefficients of as-received EDD steels in FE model was encouraging to predict the limiting dome height (LDH) close to experimental data within 6% error. Also, insights into the role of effective plastic strain consumed and strain path on decrease in LDH of pre-strained steels were analysed. Graphical abstract: fx1 Highlights: Evolution of mechanical properties of different pre-strained EDD thin steel sheets. Calibration of predicted Yld96 yield loci with experimental data. Dynamic shift of ε-FLD depending on type and amount of pre-strain was established. Use of Yld96 anisotropy plasticity theory to estimate path independent PEPS-FLD. PEPS-FLD and Yld96 anisotropy coefficients were used for FE prediction of LDH.