Trends in the Development of Machinery and Associated Technology ” TMT 2010 , Mediterranean Cruise , 11-18 September 2010 EXPERIMENTAL DETERMINATION OF FORMING LIMIT DIAGRAM
Forming limit diagrams (FLDs) are a convenient and often used tool for the classification of the formability and for the evaluation of the forming process of sheet materials. Forming limits of sheet metal are represented in the forming limit diagram (FLD) occurring by various deformation states. The paper introduces a experiment method for determination of forming limit curve for whole range of the FLD for sheet metal.
Prediction of Thickness Distribution in Sheet Metal Forming by Modified Limiting Dome Height Test with and without Blank-Holding Force
This study aims to investigate the forming behavior prediction of AISI 1008 materials using Experimental Data and simulation. Forming behavior can be understood using thickness distribution also, by which strain localization and strain distribution in the sheet metal can be studied. In this present work, the difference in the thickness distribution for different drawing ratio i.e. D/d ratio is observed. The experiment has been done using modified limiting dome height test i.e. “LDH” for different case which includes Blank holding force and without blank holding force with different blank size. In LDH test, the mechanical properties are considered in different directions i.e. rolling direction (r0), perpendicular direction (r90) and transverse direction (r45). The strain paths are chosen from Two Different blank size from drawing to stretching condition; total points have been taken for the consideration of LDH test accordingly. Circle grid marking is done on the blank by laser marking and readings is taken in the different direction. Experimental work is compared with the software HYPERFORM for the validation of the work. Experiment’s thickness Data are obtained by taking reading at each circle grid. Thickness distribution are compared for better investigation of the formability among both the cases. Keywords— LDH test, circle grid analysiss, thickness distribution, hyperform simulation.
Tailored blank design and prediction of weld line movement using the backward tracing scheme of finite element method
To achieve weight and cost reductions in component manufacturing, tailored blank is introduced for forming automotive structural skin components. In order to obtain successful application of tailored blanks without necessarily trimming after the forming process, it is critical to design an initial welded blank and to predict the weld line movement, which is usually determined by intuition and experience with the trial-and-error approach. A systematic approach method of the backward tracing scheme, which is confirmed by experiment, is extended to design the initial tailored blank for net-shape production in this study. The optimised tailored blank by the backward tracing scheme appears to be successful in obtaining a net-shape stamping product. This blank also improves the forming condition during stamping process. All simulation results show that the backward tracing scheme can be applied to more general blank design.