in this study, an extended stress-based forming limit diagram (fld) for prediction of necking based on the marciniak and kucznski (m-k) model is represented and applied in tube hydroforming. the bulge forming of a straight tube is simulated by finite element method and verified with published experimental data. this adaptive simulation technique is based on the ability to detect the onset and g...

In this study, an extended stress-based forming limit diagram (FLD) for prediction of necking based on the Marciniak and Kucznski (M-K) model is represented and applied in tube hydroforming. The bulge forming of a straight tube is simulated by finite element method and verified with published experimental data. This adaptive simulation technique is based on the ability to detect the onset an...

In this paper friction induced limit cycles are predicted for a simple motion system of a single motor-driven inertia subjected to friction and a PID-controlled regulator task. The two friction models used, i.e., (i) the dynamic LuGre friction model and (ii) the static Switch friction model, are compared with respect to the so-called hunting phenomenon. Analysis tools originating from the field...

In this paper friction induced limit cycles are predicted for a simple motion system of a single motor-driven inertia subjected to friction and a PID-controlled regulator task. The two friction models used, i.e., (i) the dynamic LuGre friction model and (ii) the static Switch friction model, are compared with respect to the so-called hunting phenomenon. Analysis tools originating from the field...

Nowadays, with extending applications of bi-layer metallic sheets in different industrial sectors, accurate specification of each layer is very prominent to achieve desired properties. In order to predict behavior of sheets under different forming modes and determining rupture limit and necking, the concept of Forming Limit Diagram (FLD) is used. Optimization problem with objective functions an...

In the metal forming process, a realistic frictional coefficient must be specified at the die/work piece interface. Several methods are developed to evaluate friction coefficient in large deformation processes. This paper presents the concept of friction calibration map to determine different frictional conditions between interfaces of die and billet in the upsetting process. One such map is ge...

Micro-stamping process is one of the most cost-effective methods to manufacture metallic bipolar plates (BPPs). This research investigates the forming of titanium thin sheet as a potential candidate for BPPs in proton exchange membrane fuel cell (PEMFC). In this regard, the process was first simulated using finite element (FE) code Abaqus. Afterward, experimental tests were implemented and the ...