linear stress analysis shows areas that yield under a one atmosphere pressure differential

1. Solidworks Simulation
Welded Cover for a sealed
Microwave electronics assembly
linear elastic stress analysis
D. Blanchet 10/19/2015

2. Fixed edges
Light blue
1 atmosphere internal
Pressure loading
On this surface
Refined graded mesh
in high stress zones
Aluminum 4047 alloy

3. Aluminum 4047 alloy stepped seal cover design used for laser welding

5. For this study assume yield strength = 12,000 psi
1,380,000 degrees of freedom
10 node tetrahedral solid elements

6. Isosurface >= 12,000 psi
Local yielding
Probable in
Red zones

7. Linear Elastic
deformation

8. High stress zones – deformation shown @ 120X
A nonlinear analysis may predict permanent deformation values.
An accurate stress strain curve for 4047 aluminum alloy is required.

9. Linear Analysis Cases
Altitude, feet Pressure
Differential, psi
Maximum
Stress, psi
Volume of
material above
12,000 psi yield
0 (leak test) 14.7 internal 86,700 2.6 %
30,000 10.0 57,850 0.9 %
50,000 12.8 74,000 1.7 %
0 (BOM test) 14.7 external 85,000 2.5 %