Sheet metal Bending using Ansys Workbench

Aim :

Sheet metal bending is to be performed according to the following conditions :

1. Aluminium Alloy 1199, Copper Alloy NL and Magnesium Alloy NL. Find out the Equivalent Stress and Total Deformation in Y direction and compare the results.
2. With the material as Aluminium Alloy, change the friction coefficient to 0.19 and run the analysis as mentioned in Case 1. Compare the results with that in case 1.
3. Refine the mesh on the plate such that it doesn't cross the academic limit. With Aluminium alloy as material, run the analysis as in Case 1 and compare the results.

FILES : Sheet_Metal_Bending

Materials Used :

Procedure :

1. The model is imported to the Ansys Workbench
   
   
   
   
   
   
2. The following Frictional Contacts where given to the parts of the model.
   

   Contact between Punch and the Sheet :

   
   

   Contact between the Die and Sheet :

   
   
   
3. Meshing Process :

   Body sizing was given to the Die and Punch with 4mm as element size :

   
   

   For the Sheet which is to be bend is given a refined mesh of element size 1mm :

   
   
   
   
4. Now for the displacement of punch we give the values in the Y-direction such that the punch is constrained Y axis only.
   
   
   
   
5. Given below is the Analysis settings :
   

Result :

CASE 1 :

Equivalent Stress :

Aluminium Alloy 1199
Copper Alloy NL
Magnesium Alloy NL

Total Directional Deformation in Y-direction :

Aluminium Alloy 1199
Copper Alloy NL
Magnesium Alloy NL

Since the Aluminium Alloy 1199 has the lowest Total Equivalent Stress of the three materials, so it is considered.

CASE 2 :

Friction Coefficient	Total Equivalent Stress(MPa)	Total Equivalent Strain	Equivalent Stress on Sheet alone(MPa)	Directional Deformation(Y-axis)
0.1	2.49E+5	1.2462	57.821	12.517
0.19	1.8641E+5	0.93412	58.8	12.382

CASE 3 :

Grid Dependency Test :

Here the mesh element size of the Sheet is reduced step by step within the Ansys License Limit. The analysis is done using parametric method to reduce individual simulation time.

Element Size(mm)	Total Equivalent Stress(MPa)	Total Equivalent Strain	Equivalent Stress on Sheet alone(MPa)	Directional Deformation(Y-axis)
1	2.49E+5	1.2462	57.821	12.617
0.8	2.43E+5	1.2160	61.313	12.56
0.6	2.23E+5	1.1193	77.559	12.420

As the mesh gets more refined the Equivalent Stress on Sheet is increasing because the simulation is getting more accurate when mesh size is decreased.