What Is Bend Radius?
The bending radius refers to the inner radius of the bent part, where t represents the thickness of the material.
When the material bends, its rounded corner is stretched on the outside layer, while the inside layer is compressed. If the material thickness is fixed, the smaller the inner r, the more severe the material stretching and compression.
If the stretching stress of the outer rounded corner exceeds the material’s ultimate strength, cracks and breaks will occur. Therefore, the structural design of bent parts should avoid overly small bending corner radii.
- For 08, 08F, 10, 10F, DX2, SPCC, E1-T52, 0Cr18Ni9, 1Cr18Ni9, 1Cr18Ni9Ti, 1100-H24, T2, the minimum bending radius is 0.4t.
- For 15, 20, Q235, Q235A, 15F, the minimum bending radius is 0.5t.
- For 25, 30, Q255, the minimum bending radius is 0.6t.
- For 65Mn, 60SiMn, 1Cr17Ni7, 1Cr17Ni7-Y, 1Cr17Ni7-DY, SUS301, 0Cr18Ni9, SUS302, the minimum bending radius is 2.0t.
Bend Radius Chart
| Item | Material | Thickness | Inside R | Die | Punch | ||
| Radius | V Width | Radius | Angle | ||||
| 1 | SPCC/SECC/SGCC | 0.8 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 2 | SPCC/SECC/SGCC | 0.9 | 1.3 | 0.5 | 6 | 0.2 | 88° |
| 3 | SPCC/SECC/SGCC | 1.0 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 4 | SPCC/SECC/SGCC | 1.2 | 1.0 | 0.4 | 6 | 0.2 | 88° |
| 5 | SPCC/SECC/SGCC | 1.2 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 6 | SPCC/SECC/SGCC | 1.5 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 7 | SPCC/SECC/SGCC | 1.6 | 1.3 | 0.5 | 8 | 0.6 | 88° |
| 8 | SPCC/SECC/SGCC | 1.8 | 2.0 | 0.8 | 12 | 0.6 | 88° |
| 9 | SPCC/SECC/SGCC | 2.0 | 2.0 | 0.8 | 12 | 0.6 | 88° |
| 10 | SPCC/SECC/SGCC | 2.3 | 2.0 | 0.8 | 12 | 0.6 | 88° |
| 11 | SPCC/SECC/SGCC | 2.5 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 12 | SPCC/SECC/SGCC | 3.0 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 13 | SPCC/SECC/SGCC | 4.0 | 4.0 | 0.8 | 25 | 0.6 | 88° |
| 14 | SPHC | 2.3 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 15 | SPHC | 3.2 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 16 | SPHC | 4.2 | 4.0 | 0.8 | 25 | 0.6 | 88° |
| 17 | SPHC | 4.8 | 4.0 | 0.8 | 25 | 0.6 | 88° |
| 18 | AL5052-H32 | 0.8 | 1.3 | 0.5 | 6 | 0.2 | 88° |
| 19 | AL5052-H32 | 1.0 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 20 | AL5052-H32 | 1.2 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 21 | AL5052-H32 | 1.5 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 22 | AL5052-H32 | 1.6 | 1.3 | 0.5 | 8 | 0.6 | 88° |
| 23 | AL5052-H32 | 1.6 | 1.3 | 0.6 | 10 | 0.6 | 88° |
| 24 | AL5052-H32 | 2.0 | 2.0 | 0.8 | 12 | 0.6 | 88° |
| 25 | AL5052-H32 | 2.3 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 26 | AL5052-H32 | 2.5 | 2.6 | 0.5 | 16 | 0.6 | 88° |
| 27 | AL5052-H32 | 3.0 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 28 | AL5052-H32 | 3.2 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 29 | AL5052-H32 | 3.5 | 4.0 | 0.8 | 25 | 1.5 | 88° |
| 30 | AL5052-H32 | 4.0 | 4.0 | 0.8 | 25 | 1.5 | 88° |
| 31 | AL5052-H32 | 5.0 | 4.0 | 0.8 | 25 | 3.2 | 88° |
| 32 | Copper | 0.8 | 1.3 | 0.5 | 6 | 0.2 | 88° |
| 33 | Copper | 1.0 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 34 | Copper | 1.2 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 35 | Copper | 1.5 | 1.3 | 0.5 | 8 | 0.2 | 88° |
| 36 | Copper | 2.0 | 2.0 | 0.8 | 12 | 0.6 | 88° |
| 37 | Copper | 2.5 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 38 | Copper | 3.0 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 39 | Copper | 3.2 | 2.6 | 0.8 | 16 | 0.6 | 88° |
| 40 | Copper | 3.5 | 4.0 | 0.8 | 25 | 1.5 | 88° |
| 41 | Copper | 4.0 | 4.0 | 0.8 | 25 | 1.5 | 88° |
