Material testing for CNC sheet forming
Materials testing can be used to predict the likely success of a given forming process. There exist a large number of standardised tests which are simple in nature, relatively cheap to perform and are normally used to provide a simple basis for comparison of materials that is relevant to a specific forming process or complete manufacturing route. However, with modern incremental processes leading to strain combinations not present in conventional forming processes, the existing range of materials testing techniques are insufficient to achieve this since they only examine in sheet tension between uniaxial and biaxial. In order to completely characterise the formability of sheet metal in processes that introduce through thickness compression or shear, further testing methods need to be devised.
Details of a novel sample design for testing pure shear can be found in the papers section. A further series of materials tests are planned that focus on out of plane stresses on formability.
A list of publications on our work to date on material testing for CNC sheet forming can be found here