42nd International Deep Drawing Research Group Conference - IDDRG 2023

Constrained groove pressing (CGP) is one of the severe plastic deformation techniques for sheet metals to impose large plastic strain and produce ultrafine-grained (UFG) structures without any change in dimensions. Cross route-constrained groove pressing (Cross-CGP), an advanced version of the conventional CGP process, involves two CGP cycles with an equivalent strain of 2.32 per cycle where...

Hole expansion ratio of ultra-high strength martensitic steels with tensile strength around 1000 MPa was evaluated. Steels were produced with direct quenching and traditional reheat and quenching processes with final thickness of 3 mm. Achieved yield strength values (Rp0.2) varied between 918 – 1068 MPa depending on the processing route. Mean hole expansion ratios (HER) in direct-quenched (DQ)...

The decarbonization of steel sheet metal production process introduces new challenges for the automotive part production process. Especially, the recyclability component, the efforts to increase the steel scrap in the primary steel making process beyond the levels currently used, produces increased variability intervals for certain residual elements outside the levels typically found in the...

The manganese-boron alloy 22MnB5 is particularly used for structural and safety-relevant parts in the automotive industry. Parts made from this alloy are usually produced using the hot stamping process. In this process, the sheet is heated to over 950 °C using an industrial roller hearth furnace. The heated sheet is then simultaneously formed and quenched in a cooled tool with a temperature...

Incremental sheet forming (ISF) is an emerging technology for manufacturing sheet metal components with fewer tools and equipment compared to conventional sheet forming. In this process, forming is generally performed without dies and punches and a simple hemispherical shaped tool can be used for shaping the final component. Forming limit in incremental sheet forming can be defined by the...

The present intention to reach fossil-free steel manufacturing will inevitably result in an increase in the use of steel scrap as a raw material for steel production. Consequently, the amounts of elements, seen as impurities, will increase in steels. This has already been seen in electric arc furnace (EAF) processed steels, where the Cu and Sn levels have doubled in some cases after 1980’s....

Robot-assisted flexible flanging (RAFF), a cost-effective and promising forming technology for producing large-size open-edge flanging parts in multi-variety and small batches, is expected to be widely used in aerospace, automotive and other technological industries. Depending on whether the flanging angle of the forming roller is adjusted, the RAFF process of every pass can be summarized as...