1 Introduction
1.1 Incremental sheet forming
1.2 Residual stress state
2 Process description and setup
Property | Hardness shore A DIN 53505 | Density | Tensile strength DIN 53504 | Tensile strain at break DIN 53504 |
---|---|---|---|---|
Symbol | – | δ | \(\sigma_{M}\) | \(\varepsilon_{M}\) |
Value | 72° ± 5 Sh A | 1.24 g/cm3 | 46 MPa | 550% |
Process | Step-down | Tool diameter | Tool rotation | Feed rate |
---|---|---|---|---|
Symbol | \(\Delta z\) | \(D_{{{\text{Tool}}}}\) | \(\theta_{{{\text{Tool}}}}\) | \(v_{{{\text{Tool}}}}\) |
Value | 2 mm | 10 mm | 300 RPM | 600 mm/min |
2.1 Residual stress measurement
2.2 Numerical process model
3 Results
3.1 Geometric accuracy
3.2 Process forces
3.3 Sheet thickness and material hardness
3.4 Superposition of compressive stresses
3.5 Residual stress state
4 Discussion
5 Summary and conclusion
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Process forces in x-, y-, and z-direction are increased by using an (elastically) deformable, i.e., flexible die.
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TPIF with the flexible die leads to a decreased sheet thickness.
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An increased material hardness was recorded for TPIF correspondingly.
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The developed knowledge can be used to produce parts with localized properties.