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In the bulk-forming operations, such as upsetting, the billets upon severe plastic deformation will fracture on reaching the threshold fracture stress. The fracture initiation and progression depends on the friction, height-to-diameter ratios (h/d), and the strength of the material. The anisotropic behavior of material is another issue that should be taken into consideration while designing the process. Macro fracture criteria, such as normalized Cockcroft, Brozzo, McClintock, and Oyane, can be better utilized to predict the fracture initiation. The Hill–von Mises criterion that incorporates the anisotropy factors (R0 and R90) was correlated with the macro failure criterion to evaluate the critical damage factor values at failure strain under plane stress condition. The process parameters, namely, friction, height-to-diameter ratios (h/d), and the strength of the material were considered, and the upsetting process was optimized using Taguchi’s design of experiment techniques with less anisotropy as desired output. After identifying the optimum result, an analysis of variance (ANOVA) analysis was performed and the contribution of each factor responsible for failure and anisotropy was also noted.

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