Fatigue analysis-based numerical design of stamping tools made of cast iron
- 316 Downloads
This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a perfect rigid body. The estimated contact pressure is then used as boundary condition for FEM structure loading analysis of the tool. The result of this analysis is compared with the critical stress limit depending on the automotive model. The acceptance of this test allows calculating the fatigue lifetime of the critical zone by using the S–N curve of corresponding load ratio. If the prescribed tool life requirements are not satisfied, then the critical region of the tool is redesigned and the whole simulation procedures are reactivated. This method is applied for a cast iron EN-GJS-600-3. The stress-failure (S–N) curves for this material is determined at room temperature under push pull loading with different load ratios R = σ min/σ max = −2, R = −1 and R = 0.1. The effects of the foundry defects are determined by SEM observations of crack initiation sites. Their presence in tested specimens is associated with a reduction of fatigue lifetime by a factor of 2. However, the effect of the load ratio is more important.
KeywordFatigue Defects Stamping Tools Cast iron
Unable to display preview. Download preview PDF.
- 1.Benslima K, Penazzi L, Mabru C, Ronde-Oustau F, Rezai-Aria F (2011) A new method for advanced virtual design of stamping tools for automotive industry: Application to nodular cast iron EN-GJS-600-3. In: ESAFORM 2011, AIP Conference Proceedings, pp. 1713–1720Google Scholar
- 8.Abebe BH (2008) Fatigue life assessment of a diesel engine pump part subjected to constant and variable amplitude loading. Master thesis, Bauhaus UniversityGoogle Scholar
- 13.Nilsson A, Birath F (2007) Topology optimization of a stamping die. In: NUMIFORM 2007, Conference Materials Processing and Design: Modeling, Simulation and Applications 908, pp. 449–454Google Scholar
- 14.Gentili A, Penazzi L, Di Pasquale E (1998) Topology optimization in sheet metal forming tool design. In: IDMME’98, pp. 449–456Google Scholar
- 16.Oudjene M, Batoz JL, Penazzi L, Mercier F (2006) A methodology for the 3D stress analysis and the design of layered sheet metal forming tools joined by screws. J Mater ProcessTechnol 189(1–3):334–343Google Scholar
- 17.del Pozo D, Lopez de Lacalle LN, Lopez JM, Hernandez A (2006) Machining of large dies based on the prediction of the press/die deformation. In: Intelligent production machines and systems 2nd I*PROMS Virtual International Conference, pp. 83–88Google Scholar