Week 5 Bending of iPhone

AIM: To perform a bend test on an iPhone model using ANSYS Workbench

Case 1: Simulate the model as it is given in the video.

Case 2: Move the bottom fingers from their defined position to the given position X= 22.5mm & Z= 10mm and obtain the results for the simulation. Also, define the S-N curve for the Aluminium Alloy material as per values given below and determine the fatigue life results for the same.

Stress, MPa	Number of Cycles, N
225	10000
175	100000
143	1000000
110	10000000
80	100000000

Results and Deliverables

• Obtain the directional deformation for the model
• The factor of Aluminium Alloy NL
• Life of the Aluminium alloy for the case
• Compare the results and present them with the conclusion

PROCEDURE:

The following geometry was imported into ANSYS as shown below:

The geometry includes the phone consisting of Aluminium chassis, display and interiors. The display is assigned to be glass and the interiors are assigned to be Polyethylene. The fingers are assumed to be structural steel with rigid behaviour because in this case they are used strictly for creating force. The material properties of glass are given below:

The fingers are given a fixed joint as shown below:

The two thumbs are given translational joint as shown below:

MESH:

Mesh with a face sizing of 4mm is used on the areas of interest such as fingers and frame.

ANALYSIS SETTINGS:

RESULTS:

CASE-1: When bending action is performed from one of the longitudinal sides of the phone (Simulate the model as it is given in the video)

Directional Deformation = 5.226 mm

Equivalent Stress: 329.72 MPa

Equivalent Strain: 0.005574

CASE-2:

Move the bottom fingers from their defined position to the given position X= 22.5mm & Z= 10mm and obtain the results for the simulation. Also, define the S-N curve for the Aluminium Alloy material as per values given below and determine the fatigue life results for the same.

Stress, MPa	Number of Cycles, N
225	10000
175	100000
143	1000000
110	10000000
80	100000000

Directional Deformation = 4.721 mm

Equivalent Stress: 290.2 MPa

Equivalent Strain: 0.057311

Safety Factor: 1.e+009 cycles (Design Life)

CONCLUSION - FIRST:

CONCLUSION - SECOND:

Fatigue Life CASE-1: 1x10^08 cycles

Fatigue Life CASE-2: 1x10^08 cycles

The fatigue life for the given cycle is better for the second case. The animation files have been attached for reference:

Safety Factor CASE-1: 1.e+009 cycles (Design Life)

Safety Factor CASE-2: 1.e+009 cycles (Design Life)

The safety factor (0.275>0.223) for the given cycle is better for the second case. The animation files have been attached for reference: