Forming Limit Diagrams

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. 

Among the methodologies to evaluate form-ability, forming limit diagrams plays a relevant role. 

Formability (Damage), Fig. 4 Forming limit diagrams defined by Keeler and Goodwin (Goodwin 1968)... 

The formability limits of a sheet metal were described by Keeler in the form of a forming limit diagram (FLD) [771. FLDs are dependent on bulk material properties, geometry of deformation, strain history (or strain path), sheet thickness, and the characteristics of the tool-sheet interface. Thus, the FLD acts only as an indicator of formability and cannot be regarded as a material property 178]. 

Figure 31 Forming limiting diagram of various sheet metals. (From Ref. 3.)...

Figure 28 Combined forming and wrinkling limit diagram. (From Ref. 69.)...

Figure 5.15 Carbon limit diagram. Principle of equilibrated gas. Carbon is formed for conditions to the left of the curves. Curves 1 and 2 represent graphite data and whisker carbon (Appendix 2), respectively. The dotted hnes show feed gas compositions leading to product gas with indicated H2/CO ratios [152]. Reproduced with the permission of...

There are no available data about the phase diagram of the Sc-Pr system. Taking into consideration the data on the Sc-Ce system it is possible to predict a complete mutual miscibility of the components in each other in liquid and in bcc solid phases. aSc and aPr have different crystal structures (hep and dhep respectively), therefore, they probably form limited solid solutions. 

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