Iterative springback compensation of NUMISHEET benchmark #1

Upon unloading after the forming stage, a sheet metal product will spring back due to internal stresses. Springback\ud is a major problem for process-planning engineers. In industrial practise, deformations due to springback are compensated\ud manually, by doing extensive measurements on prototype parts, and altering the tool geometry by hand. This is a time\ud consuming and costly operation. In this paper the application of two compensation algorithms, based on the finite element\ud simulation of the forming process are discussed. The smooth displacement adjustment (SDA) method and the springforward\ud (SF) method have been applied to several industrial products, such as the NUMISHEET 2005 benchmark#1. With the SDA\ud method successful compensations have been carried out. For the SF method some principal problems remain