Week 5 Bending of iPhone

iPhone bending Report

Aim: For this challenge, simulate the bending of iPhone as per the given cases below:

• 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
• Factor of Aluminium Alloy NL

• Life of the Aluminium alloy for the case
• Compare the results and present with the conclusion.

Procedure:

• Select Static Structural, drag and drop into Project Schematic.
• Choose materials Structural Steel, Aluminium Alloy NL, Glass and Polyurethane under Engineering Data.
• Add the given tabular data under SN Curve of Al Alloy in Engineering data.
• Under geometry tab, import the given geometry, double-click to open Space Claim to register the model.
• Then in Mechanical Module, assign Structural Steel to the fingers, Aluminium Alloy NL to the frame, Glass to the display and polyurethane to the insides of the iPhone.
• Assign a bonded connection between the display and the frame.
• The other connections including display to insides, display to fingers, frame to insides, frame to fingers can be left frictionless.
• All the fingers can be assigned a fixed joint except for the pushing fingers (thumbs). The pushing fingers must have a translational joint.
• The mesh size was set to default, and the pushing fingers’ upper faces were given a 4mm face sizing.
• Under static structural tab, we set the analysis to 8 steps with auto timestep as programmed.
• The upper and lower faces (vertically) of the frame are given a fixed support.
• The left and right faces (horizontally) of the frame are allowed a displacement along Y axis.
• Both the pushing fingers are given a joint displacement along Y-axis in 8 steps, ensuring it pushes the frame and retreats.
• Directional Deformation in Z-axis, Equivalent Plastic Strain and Equivalent Stress plots are requested from the solver as outputs.
• Also requesting Fatigue tool gives us life and safety factor.
• Run the simulation by clicking on “solve”.
• Repeat the same steps in case 2, but after moving the pushing fingers by (22.5, 0, 10).

Case 1:

Case 2:

Conclusion:

From the two cases, here is the inference:

Case	Stress in Al-Alloy (MPa)	Strain in Al-Alloy	Directional Deformation (mm)
Case 1	594.45	0.0085657	7.9345
Case 2 - Thumbs Moved by (22.5,0,10)	468.05	0.0066759	4.633

We can observe that the stress, strain and deformation has reduced after moving the position of pushing fingers.

Safety factor of case 1: 15

Safety factor of case 2: 10.63