Cranial Reconstruction using Double Side Incremental Forming

Incremental sheet forming (ISF) is a highly versatile and flexible process for rapid manufacturing of complex sheet metal parts. Comparing to conventional sheet forming processes, ISF is of a clear advantage in manufacturing small batch or customized products such as cranial implant. Although effort on cranial reconstruction by using incremental sheet forming approach has been made in recent years, research has been mostly based on the single point incremental forming (SPIF) strategy and there are still considerable technical challenges for achieving better geometric accuracy, thickness distribution and complex cranial shape. In addition, the use of a backing plate or supporting die reduces the process flexibility and increases the cost. To overcome these limitations, double side incremental sheet forming (DSIF) process is employed for forming Grade 1 pure titanium sheet by using different toolpath strategies. The geometric accuracy and thickness distribution of the final part are evaluated so the optimized tool path strategies are developed. This leads to an assessment of the DSIF based approach for the application in cranial reconstruction.