Introduction
Linear viscoelastic material models can be combined with Time-Temperature-Superposition (TTS) in order to generate a Master Curve capable of predicting the response at all temperatures. In MCalibration the linear viscoelastic and TTS models can be calibrated all at once. This works, but in practice can be difficult to perform due to the non-linear coupling between the material model and the TTS shifting. For this reason, MCalibration now also supports a new function for directly generating the master curve from data obtained at different temperatures. This article explains how this new function works. Note that this new feature works in MCalibration 7.2.1 and later.
Master Curve from DMA Data
The first step is to create a single csv-file that contains all DMA temperature sweep data in one file. This file should have one column that lists the temperature (see image below).

The second step is to click on the “Create TTS Master” button to bring up the following dialog. Specify what target temperature you want the data to be for, and then click on OK.

The master curve is then automatically generated for the selected target temperature (see image below). You can then create a Load Case based on the experimental data in the table.

Master Curve from Stress Relaxation Data
MCalibration can also generate a master curve stress relaxation or creep data obtained at different temperatures. To use this feature first create a csv/text file that contains the results from all stress relaxation tests. Simply paste the data from each temperature, one after another, into one file with all data. Then load that into the “Clean Data” tab in MCalibration (see image below).

To generate the master curve, click the “Create TTS Master” button, select the target temperature, then click “OK”.

MCalibration will then generate the Master Curve. Life is good!
