Wire bending Simulation

OBJECTIVE:

To perform an analysis to simulate the bending of a wire. Use wire material as Copper Alloy (Non Linear), Aluminium Alloy (Non Linear) and Magnesium Alloy (Non Linear). Find out the Equivalent stress and Equivalent strain on the wire alone and compare the results

SOLUTION:

Step 1: Model

The model was used as given, without any modifications,

Step 2: Material

The model consists of three bodies namely, wheel, lever and wire. Here the analysis focuses on the changes in strain and stress in the wire for different materials. Hence the material for wheel and lever is assigned the same for all cases and the wire material was used as copper alloy NL, aluminium alloy NL and magnesium alloy NL. The properties are as given below:

Step 3: Connections

Two contacts were defined between the bodies, one between the wheel and wire and the other between the wire and lever. The contacts were defined as frictional with coefficient of friction as 0.2, normal stiffness factor was 0.1 and stiffness was updated in every iteration. The formulation method is augmented lagrange and the interface treatment is add offset with ramped effects. In order to facilitate the rotation of the lever, a revolute joint was defined on the lever.

Step 4: Meshing

The meshing was done using ANSYS mesher. All the elements were of tetrahedron shape with the contact regions having elements of size 2.2mm and the curved contact region in the wheel having a element size 0.8mm.

Step 5: Analysis settings

The analysis was carried over 8 steps, with initial time step 0.1sec, minimum time step 0.01sec and maximum time step 1 second. The solver type is made direct, weak springs was program controlled and large deflection was turned on. The wheel and the end of the wire inside the slot provided in the wheel was given fixed condition. The lever was given a rotation ranging from 0 to 140 degree.

Step : Results

The following figures illustrate the equivalent stress and strain on the wire for each of the 3 materials.

Material	Max equivalent stress	Max equivalent strain
Copper alloy NL	332.08	0.0030433
Aluminium alloy NL	335.1	0.0047573
Magnesium alloy NL	248.95	0.005547