This paper proposes a new method to design the optimal load curves. In order to assess the mathematical models, a combination of design of experiment and finite element simulation was used. Optimum set of loading variables were obtained by embedding the mathematical models for tube formability indicators into simulated annealing (SA) algorithm. The adequacy of optimum results was evaluated by genetic algorithm (GA). Using the utilized method, the effect of all loading variables were considered in hydroforming of T-shaped tubes. Eliminating of variables with lower effect could decline the complexity of problem and help designers to study the effect of other parameters such as geometrical conditions and loading parameters. Applying the optimal load paths attained from the proposed method caused an improvement in thinning rate despite of using less pressure capacity.

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