Design of U-Geometry Parameters Using Statistical Analysis Techniques in the U-Bending Process
Abstract
:1. Introduction
2. Finite Element Method (FEM) Simulations and Experimental Procedures
2.1. FEM Simulation Model
2.2. Experimental Procedures
2.3. Statistical Analysis Techniques
3. Results and Discussion
3.1. Effects of U-Geometry Parameters on the Spring-Back Characteristic
3.1.1. Channel Width
3.1.2. Workpiece Thickness
3.1.3. Bend Angle
3.1.4. Tool Radius
3.1.5. Workpiece Length
3.2. The Use of FEM Simulation and Its Validation
3.3. Statistical Analysis
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Simulation Model | Plane Strain Model | |
---|---|---|
Object types | Workpiece: Elasto-plastic Punch/Die/Pad: Rigid | |
Workpiece material | A1100-O (JIS) Ultimate tensile stress (σu): 102.5 MPa Elongation (δ): 43.5% Plastic anisotropy (r0): 0.521 Young’s modulus (E): 69000 MPa Poisson’s ratio (ν): 0.33 | |
Friction coefficient (µ) | 0.1 | |
Flow curve equation | ||
Punch velocity | 30 mm/min | |
Pressure pad velocity | 30 mm/min | |
Workpiece geometries | Thickness (t) | With pad: 3 mm, 4 mm, 5 mm |
Without pad: 1 mm, 2 mm, 3 mm | ||
Length (WPL): 120 mm, 125 mm, 130 mm | ||
U-die geometries | Tool radius (Rp) | With pad: 5 mm, 6 mm, 7 mm |
Without pad: 3 mm, 4 mm, 5 mm | ||
Bend angle (θ): 90°, 105°, 120° | ||
Channel width (W): 30 mm, 45 mm, 60 mm | ||
Upper die radius (Rud): 5 mm | ||
Depth of U-die (D): 35–55 mm |
Parameters | Parameter Levels | Units | |||
---|---|---|---|---|---|
Low | Medium | High | |||
Channel width (W) | With pad | 30 | 45 | 60 | mm |
With no pad | |||||
Bend angle (θ) | With pad | 90 | 105 | 120 | ° |
With no pad | |||||
Workpiece length (WPL) | With pad | 120 | 125 | 130 | mm |
With no pad | |||||
Tool radius (Rp) | With pad | 5 | 6 | 7 | mm |
With no pad | 3 | 4 | 5 | ||
Workpiece thickness (t) | With pad | 3 | 4 | 5 | mm |
With no pad | 1 | 2 | 3 |
FEM No. | U-Geometry Parameters | Spring-Back (°) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
θ | Wp | Rp | t | WPL | ||||||||
with Pad | with no Pad | with Pad | with no Pad | with Pad | with no Pad | with Pad | with no Pad | with Pad | with no Pad | with Pad | with no Pad | |
1 | 90 | 90 | 30 | 30 | 5 | 3 | 3 | 1 | 120 | 120 | 1.11 | 0.33 |
2 | 120 | 90 | 30 | 30 | 5 | 3 | 3 | 1 | 120 | 130 | 0.29 | 0.80 |
3 | 90 | 90 | 60 | 30 | 5 | 3 | 3 | 3 | 120 | 120 | 1.56 | 0.67 |
4 | 120 | 90 | 60 | 30 | 5 | 3 | 3 | 3 | 120 | 130 | 0.34 | 0.93 |
5 | 90 | 90 | 30 | 30 | 7 | 5 | 3 | 1 | 120 | 120 | 1.25 | 0.69 |
6 | 120 | 90 | 30 | 30 | 7 | 5 | 3 | 1 | 120 | 130 | 0.32 | 0.93 |
7 | 90 | 90 | 60 | 30 | 7 | 5 | 3 | 3 | 120 | 120 | 1.62 | 0.50 |
8 | 120 | 90 | 60 | 30 | 7 | 5 | 3 | 3 | 120 | 130 | 0.49 | 0.78 |
9 | 90 | 90 | 30 | 60 | 5 | 3 | 5 | 1 | 120 | 120 | 0.95 | 0.57 |
10 | 120 | 90 | 30 | 60 | 5 | 3 | 5 | 1 | 120 | 130 | 0.06 | 0.52 |
11 | 90 | 90 | 60 | 60 | 5 | 3 | 5 | 3 | 120 | 120 | 1.31 | 0.95 |
12 | 120 | 90 | 60 | 60 | 5 | 3 | 5 | 3 | 120 | 130 | 0.04 | 0.96 |
13 | 90 | 90 | 30 | 60 | 7 | 5 | 5 | 1 | 120 | 120 | 1.45 | 0.36 |
14 | 120 | 90 | 30 | 60 | 7 | 5 | 5 | 1 | 120 | 130 | 0.33 | 0.42 |
15 | 90 | 90 | 60 | 60 | 7 | 5 | 5 | 3 | 120 | 120 | 1.39 | 0.69 |
16 | 120 | 90 | 60 | 60 | 7 | 5 | 5 | 3 | 120 | 130 | 0.37 | 0.55 |
17 | 90 | 120 | 30 | 30 | 5 | 3 | 3 | 1 | 130 | 120 | 1.52 | 1.07 |
18 | 120 | 120 | 30 | 30 | 5 | 3 | 3 | 1 | 130 | 130 | 0.24 | 1.74 |
19 | 90 | 120 | 60 | 30 | 5 | 3 | 3 | 3 | 130 | 120 | 1.54 | 0.25 |
20 | 120 | 120 | 60 | 30 | 5 | 3 | 3 | 3 | 130 | 130 | 0.36 | 0.16 |
21 | 90 | 120 | 30 | 30 | 7 | 5 | 3 | 1 | 130 | 120 | 1.93 | 0.87 |
22 | 120 | 120 | 30 | 30 | 7 | 5 | 3 | 1 | 130 | 130 | 0.27 | 1.56 |
23 | 90 | 120 | 60 | 30 | 7 | 5 | 3 | 3 | 130 | 120 | 1.65 | 0.63 |
24 | 120 | 120 | 60 | 30 | 7 | 5 | 3 | 3 | 130 | 130 | 0.47 | 0.53 |
25 | 90 | 120 | 30 | 60 | 5 | 3 | 5 | 1 | 130 | 120 | 1.30 | 1.00 |
26 | 120 | 120 | 30 | 60 | 5 | 3 | 5 | 1 | 130 | 130 | 0.08 | 1.87 |
27 | 90 | 120 | 60 | 60 | 5 | 3 | 5 | 3 | 130 | 120 | 1.33 | 0.42 |
28 | 120 | 120 | 60 | 60 | 5 | 3 | 5 | 3 | 130 | 130 | 0.05 | 0.38 |
29 | 90 | 120 | 30 | 60 | 7 | 5 | 5 | 1 | 130 | 120 | 1.45 | 1.71 |
30 | 120 | 120 | 30 | 60 | 7 | 5 | 5 | 1 | 130 | 130 | 0.33 | 1.31 |
31 | 90 | 120 | 60 | 60 | 7 | 5 | 5 | 3 | 130 | 120 | 1.39 | 0.73 |
32 | 120 | 120 | 60 | 60 | 7 | 5 | 5 | 3 | 130 | 130 | 0.34 | 0.45 |
33 | 105 | 105 | 45 | 45 | 6 | 4 | 4 | 2 | 125 | 125 | 0.30 | 2.71 |
34 | 90 | 90 | 45 | 45 | 6 | 4 | 4 | 2 | 125 | 125 | 1.52 | 2.53 |
35 | 120 | 120 | 45 | 45 | 6 | 4 | 4 | 2 | 125 | 125 | 0.38 | 2.62 |
36 | 105 | 105 | 30 | 30 | 6 | 4 | 4 | 2 | 125 | 125 | 0.41 | 1.50 |
37 | 105 | 105 | 60 | 60 | 6 | 4 | 4 | 2 | 125 | 125 | 0.47 | 2.16 |
38 | 105 | 105 | 45 | 45 | 5 | 3 | 4 | 2 | 125 | 125 | 0.42 | 2.15 |
39 | 105 | 105 | 45 | 45 | 7 | 5 | 4 | 2 | 125 | 125 | 0.41 | 2.68 |
40 | 105 | 105 | 45 | 45 | 6 | 4 | 3 | 1 | 125 | 125 | 0.33 | 1.65 |
41 | 105 | 105 | 45 | 45 | 6 | 4 | 5 | 3 | 125 | 125 | 0.47 | 1.18 |
42 | 105 | 105 | 45 | 45 | 6 | 4 | 4 | 2 | 120 | 120 | 0.46 | 2.16 |
43 | 105 | 105 | 45 | 45 | 6 | 4 | 4 | 2 | 130 | 130 | 0.45 | 2.37 |
Parameters | SStreatment | % Contributions | ||
---|---|---|---|---|
with Pad | with no Pad | with Pad | with no Pad | |
Bend angle (θ) | 12.52 | 0.39 | 91.07 | 1.81 |
Workpiece thickness (t) | 0.28 | 1.10 | 2.01 | 5.11 |
Tool radius (Rp) | 0.19 | - | 1.37 | - |
Channel width (W) | - | 0.01 | - | 0.05 |
Workpiece length (WPL) | - | 0.14 | - | 0.66 |
Bend angle (θ) × Bend angle (θ) | 0.76 | - | 5.55 | - |
Channel width (W) × Channel width (W) | - | 13.17 | - | 60.93 |
Workpiece thickness (t) × Workpiece thickness (t) | - | 3.67 | - | 16.96 |
Bend angle (θ) × Workpiece thickness (t) | - | 2.82 | - | 13.05 |
Workpiece thickness (t) × Workpiece length (WPL) | - | 0.31 | - | 1.43 |
Total | 13.75 | 21.61 | 100.00 | 100.00 |
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Phanitwong, W.; Boochakul, U.; Thipprakmas, S. Design of U-Geometry Parameters Using Statistical Analysis Techniques in the U-Bending Process. Metals 2017, 7, 235. https://doi.org/10.3390/met7070235
Phanitwong W, Boochakul U, Thipprakmas S. Design of U-Geometry Parameters Using Statistical Analysis Techniques in the U-Bending Process. Metals. 2017; 7(7):235. https://doi.org/10.3390/met7070235
Chicago/Turabian StylePhanitwong, Wiriyakorn, Untika Boochakul, and Sutasn Thipprakmas. 2017. "Design of U-Geometry Parameters Using Statistical Analysis Techniques in the U-Bending Process" Metals 7, no. 7: 235. https://doi.org/10.3390/met7070235