Ramberg-Osgood coefficient calculations

When exporting results into structural analysis packages, the behaviour of the material in the non-linear region of the stress-strain curve is important. The Ramberg-Osgood equation predicts this behaviour based on experimental data.

Stress-strain information for the material can be entered or imported into the Thermoplastics Material - Stress-Strain dialog. For each unique set of temperature, relative humidity, and strain rate the Ramberg-Osgood equation can be generated provided there are enough data points to generate the required coefficients.

Each unique test condition requires the following data.

1. At least fifteen data points for each test angle relative to the direction of polymer flow.
2. A minimum of two test angles. 0°, 45° and 90° are the only angles currently supported.
3. Tension data only, compression data will be ignored.

By selecting Plot data from the Stress-Strain dialog, any Ramberg-Osgood generated curve will be displayed alongside the experimental data.