In this example, 3-point bending analysis of a phone is performed to check the
flexural strength of the phone.
The objective is to analyze the stresses and displacement of the phone when it is
pressed by pressing cylinder from top and constrained by the fixed cylinder at the
bottom.
Model Files
Before you begin, copy the file(s) used in this example to
your working directory.
The phone containing all the parts inside is subjected to bending using pressing
cylinder. The phone parts are given appropriate contacts and material. The 3-point
bending analysis of the phone is performed using RBODY. The lower
cylinders are fixed, the phone is resting on it and the pressing cylinder is given
displacement of 8 mm.
PCB Material Properties
Young's modulus
15000
Poisson's ratio
0.3
Density
3e-9
Battery Material Properties
Young's modulus
2000
Poisson's ratio
0.3
Density
2.5e-09
PCB Comps
Young's modulus
2000
Poisson's ratio
0.3
Density
2.e-09
Bolt and carrier plate
Steel nonlinear material
Frame, button and front back cover (polymer plastic)
Young's modulus
2000
Poisson's ratio
0.4
Density
1.1e-9
Table 1. Stress Strain Plot Values
Strain
Stress
0
50
0.01
55
0.1
60
0.3
65
Glass
Young's modulus
70000
Poisson's ratio
0.3
Density
2.5e-9
Carrier plastic (glass fiber plastic)
Young's modulus
10000
Poisson's ratio
0.4
Density
1.4e-9
Table 2. Stress Strain Plot Values
Strain
Stress
0
100
0.01
120
0.054
140
Gasket
Gasket material, MATHE, Model
OGDEN
Buttons rubber
Rubber material, MATHE, Model
OGEDEN
Results
Displacement plot of phone bending:
Stress plot:
With a stress of 587 on the glass of the phone indicates that glass will break
at the location (Figure 3).