OS-E: 8000 3-Point Bending of Phone

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

Refer to Access the Model Files to download the required model file(s).

The model file used in this example includes:

3point_bending_of_Phone.fem

Model Description

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 $[MPa]$
Poisson's ratio: 0.3
Density: 3e-9 $[\frac{k g}{m m^{3}}]$

Battery Material Properties
Young's modulus: 2000 $[MPa]$
Poisson's ratio: 0.3
Density: 2.5e-09 $[\frac{k g}{m m^{3}}]$

PCB Comps
Young's modulus: 2000 $[MPa]$
Poisson's ratio: 0.3
Density: 2.e-09 $[\frac{k g}{m m^{3}}]$

Bolt and carrier plate: Steel nonlinear material

Frame, button and front back cover (polymer plastic)
Young's modulus: 2000 $[MPa]$
Poisson's ratio: 0.4
Density: 1.1e-9 $[\frac{k g}{m m^{3}}]$

Table 1. Stress Strain Plot Values
Strain	Stress
0	50
0.01	55
0.1	60
0.3	65

Glass
Young's modulus: 70000 $[MPa]$
Poisson's ratio: 0.3
Density: 2.5e-9 $[\frac{k g}{m m^{3}}]$

Carrier plastic (glass fiber plastic)
Young's modulus: 10000 $[MPa]$
Poisson's ratio: 0.4
Density: 1.4e-9 $[\frac{k g}{m m^{3}}]$

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:

Figure 2. Displacement Contour
Stress plot:

Figure 3. Stress Contour

With a stress of 587 $[MPa]$ on the glass of the phone indicates that glass will break at the location (Figure 3).