Fracture forming limits diagram

Forming Limit Analysis. The ductihty of sheet and strip can be predicted from an analysis that produces a forming limit diagram (ELD), which defines critical plastic strains at fracture over a range of forming conditions. The ELD encompasses the simpler, but limited measures of ductihty represented by the percentage elongation from tensile tests and the minimum bend radius from bend tests. 

Formability (Damage), Fig. 5 Forming limit diagrams for necking and for fracture... 

Fig. 5.10. Failure-assessment diagram (after [21]) in standardised form for Y = const. The arrows show how the state of the loaded component changes when the corresponding parameter is raised. Thus, increasing the limiting stress criimit or the initial crack length a increases the tendency for failure by crack propagation, whereas increasing the fracture toughness Kic decreases it. Within the region marked with EPFM, elastic-plastic fracture mechanics has to be used because the plastic zone near the crack tip is not small. This theory is the topic of section 5.3...

Here is a solvated ion, e is an electrom, and n represents the ion state of charge. The electrons, liberated by the oxidation, must flow through the material M to be consumed in an appropriate cathodic reaction. Beyond a solubility limit, precipitates of hydroxide or hydrated oxide are formed, and this surface film can provide a barrier to further dissolution. In fact, there are two film formation mechanisms the dissolution-precipitation mechattism addressed before and also the solid-state oxidation proeess M + H2O MO + 2H+ + 2e. Some films are termed passive, for stainless steels or aluminum alloys, for instance. These films can play an important role in environment-sensitive erack mitiation and fracture. Under thermodynamic equilibrium conditions, the film stability may be inferred from E =y(pH) diagrams, where E is the electrical potential related to the chemical free energy G by G = -nEF, and F is Faraday s ntrmber. At eqirilibrium, one can define the electrode potential (related to AG) and the eurrent density 1(1 ... 

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