Finite element analysis and experimental validation of flashless cold forging of propeller hubs and blade of autonomous underwater vehicle

In this paper three-dimensional finite element method analysis and experimental flashless cold forging of aluminium front and back hubs, and the blade of an autonomous underwater vehicle propeller are presented. The rigid-plastic finite element simulation is performed using Deform F-3V6.0, to estimate the optimum load required for the flashless cold forging. The complex profiles of the hubs and blade are modelled using Solidworks SP4.02007, which is also used for the modelling of the workpiece and die-punch assembly. The workpiece used is of AISI AL6061 and the die material is die steel (AISI D2). The process is optimized to form the propeller back and front hubs, and the blade. For all the models, three workpieces with different specifications are selected and investigated to obtain the optimum workpiece that gives flashless cold forging with no underfilling. Based on the simulation results, the flashless cold forging is successfully done on a 100 tonne C-type machine. The experimental forged samples conform well with the simulated models.