Bending-Additive-Machining Hybrid Manufacturing of Sheet Metal Structures

The ever-increasing industry innovation demands a paradigm of manufacturing process that is capable of accomplishing multiple tasks on a single component. Majority of structural parts require bending of metal sheets with high degree of accuracy. In many applications bent parts with additional features are sought out for various special purposes. Clearly there is a need calling for the integration of different manufacturing processes to reach a synergistic effect [4, 5]. Traditionally a combination of additive manufacturing and machining is used to alleviate the constraints set forth by machining alone. However this hybrid approach is still constrained by both the limited cutter accessibility and gravity-imposed deposition direction. This paper presents a new Hybrid Manufacturing configuration by combining bending, deposition and machining processes. The major advantage of this new approach hinges on the deliberate use of bending process by providing additional accessibility that is not available on traditional additive – machining setup. Essentially the accessibility issue is overcome by introducing an intermediate bending step so that both metal deposition and removal can be conducted in the process-required orientation. As bending is part of this new hybrid process, springback is also inherent to this new hybrid manufacturing approach. This research incorporates the consideration of both springback compensation and cold hardening effect in the selection of intermediate bending step. Examples are also provided to show the efficacy of this new hybrid manufacturing approach.