Single- and multi-objective optimization of internal gear flowforming process based on increasing tooth height and reducing force and built-up edge

Flowforming is an incremental metal forming process in which deformation occurs gradually between the roller and mandrel. This process has been widely used for manufacturing of high-precision tubular parts and seamless tubes. Internal gear flowforming process is a new method for manufacturing an internal gear that requires no additional machining process. In this study, the design of experiment method and regression analysis were used to obtain tooth height, force, and built-up edge as functions of the effective parameters, including feed rate, roller diameter, attack angle, and thickness reduction percentage. Next, the simulated annealing and genetic algorithm were used for, respectively, single- and multi-objective optimization of the obtained functions. The goal of optimization was to reduce the force and built-up edge and increase the tooth height. In single-objective optimization, the maximum tooth height was 0.576 mm, the minimum force was 1606.63 N, and the minimum built-up edge was 0.448 mm. In multi-objective optimization, an optimal set of tooth height, force, and built-up edge (Pareto front) is obtained.