Softening temperature

The Vicat softening temperature is measured in accordance with ISO 306 using a needle-shaped indenter that is subjected to a defined heating rate. The measurement is taken when the indenter reaches a certain depth. There are four methods: VST/A/50, VST/A/120, VST/B/50 and VST/B/120, where "A" stands for a test load of 10 N and "B" for 50 N. The numbers 50 and 120 respectively represent the heating rate in K per hour.