Two-layer metallic sheets have wide applications in various industries due to their superlative characteristics. This paper presents analytical model to investigate the formability of two-layer sheets based on Marciniak and Kuckzinsky (M-K) method using Barlat and Lian non-quadratic yield criterion. FEM simulation is also performed to calculate the forming limits based on bifurcation theory. Fo...

superplastic materials show huge amount of deformation in low strain rates and temperature above half of melting point. in superplastic forming, estimating the pressure–time diagram and thickness distribution has significant importance. utilizing numerical methods, the involved parameters in superplastic forming can be optimized for such estimations. in the present paper, the simulation of supe...

The purpose of this investigation is to examine the viability of using the sheet metal for forming applications. Forming limit diagram (FLD) composed of negative and positive minor strain with respect to major strain which occurs at directional zero strain with the critical thickness of sheet metal. The negative minor strain region of FLD is predicted by localized necking. However there is no d...

In this paper, a new approach is proposed for stress state - dependent flow localization in bifurcation failure model bounded through ductile damage in dynamically loaded sheets. Onset of localized necking is considered in phenomenological way for different strain rates to draw the forming limit diagram (FLD). Using a strain metal hardening exponent in the Vertex theory related to the strain ra...

two-layer metallic sheets have wide applications in aerospace, marine, automotive and domestic industries due to their superlative characteristics. in this paper, the formability of two-layer sheet is investigated through analytical, experimental and numerical approaches. an analytical model is developed based on marciniak-kuczynski method associated hill’s non-quadratic yield criterion. formin...

The forming limit diagram (FLD) is probably the most common representation of sheet metal formability and can be defined as the locus of the principal planar strains where failure is most likely to occur. Low carbon steel sheets have many applications in industries, especially in automotive parts, therefore it is necessary to study the formability of these steel sheets. In this paper, FLDs, wer...