Create a new material that includes the fatigue data to be used in the analysis.
Helius PFA requires specific material parameters in order to predict the fatigue life of composite materials accurately. Here we will cover creating a new material using Composite Material Manager and defining S-N data to be used in a progressive fatigue analysis. For more information on Composite Material Manager and the S-N data required for a fatigue analysis, you are directed to the Unidirectional Fatigue Tab and Woven Fatigue Tab sections of the Composite Material Manager User's Guide. This tutorial requires the use of AS4-PEEK (a unidirectional material).
The material to be created is AS4_PEEK, with engineering constants defined in the table below and a fiber volume fraction of 0.61 [1].
| E11 (GPa) | E22 (GPa) | E33 (GPa) | ν12 | ν13 | ν23 | G12 (GPa) | G13 (GPa) | G23 (GPa) |
|---|---|---|---|---|---|---|---|---|
| 138.3 | 9.7 | 9.7 | 0.301 | 0.301 | 0.343 | 5.87 | 5.87 | 3.61 |
The strengths of the material are given in the table below [1].
| +S11 (MPa) | -S11 (MPa) | +S22 (MPa) | -S22 (MPa) | +S33 (MPa) | -S33 (MPa) | S12 (MPa) | S13 (MPa) | S23 (MPa) |
|---|---|---|---|---|---|---|---|---|
| 1904 | 1400 | 74.8 | 240 | 74.8 | 240 | 66.3 | 66.3 | 50 |
The longitudinal S-N lamina test data is given in the table below with a load ratio of 0.1 and a frequency of 10 Hz.
| S (Pa) | Cycles to Failure | Frequency (Hz) | Load Ratio | Angle (°) |
|---|---|---|---|---|
| 1.655E+09 | 6.056E+01 | 10 | 0.1 | 0.0 |
| 1.197E+09 | 1.741E+03 | 10 | 0.1 | 0.0 |
| 1.407E+09 | 2.520E+03 | 10 | 0.1 | 0.0 |
| 1.219E+09 | 8.930E+03 | 10 | 0.1 | 0.0 |
| 1.134E+09 | 1.481E+04 | 10 | 0.1 | 0.0 |
| 9.822E+08 | 1.995E+04 | 10 | 0.1 | 0.0 |
| 8.977E+08 | 3.886E+05 | 10 | 0.1 | 0.0 |
| 8.977E+08 | 5.882E+05 | 10 | 0.1 | 0.0 |
The transverse S-N lamina test data is given in the table below with a load ratio of 0.1 and a frequency of 10 Hz [1].
| S (Pa) | Cycles to Failure | Frequency (Hz) | Load Ratio | Angle (°) |
|---|---|---|---|---|
| 3.247E+08 | 9.554E+02 | 10 | 0.1 | 10 |
| 3.026E+08 | 1.614E+05 | 10 | 0.1 | 10 |
| 2.772E+08 | 3.348E+05 | 10 | 0.1 | 10 |
| 2.539E+08 | 1.982E+06 | 10 | 0.1 | 10 |
| 1.170E+08 | 1.476E+03 | 10 | 0.1 | 30 |
| 1.130E+08 | 6.203E+04 | 10 | 0.1 | 30 |
| 1.000E+08 | 7.961E+05 | 10 | 0.1 | 30 |
| 9.153E+07 | 2.122E+03 | 10 | 0.1 | 45 |
| 8.679E+07 | 6.485E+04 | 10 | 0.1 | 45 |
| 8.230E+07 | 4.821E+05 | 10 | 0.1 | 45 |
| 7.943E+07 | 4.702E+04 | 10 | 0.1 | 60 |
| 7.017E+07 | 1.143E+05 | 10 | 0.1 | 60 |
| 7.017E+07 | 1.683E+05 | 10 | 0.1 | 60 |
| 6.793E+07 | 4.384E+03 | 10 | 0.1 | 90 |
| 6.113E+07 | 7.232E+04 | 10 | 0.1 | 90 |
| 5.311E+07 | 1.399E+05 | 10 | 0.1 | 90 |
| 4.951E+07 | 1.531E+06 | 10 | 0.1 | 90 |