scope:

This International Standard specifies four methods for the determination of the Vicat softening temperature (VST) of thermoplastic materials: - Method A50 using a force of 10 N and a heating rate of 50° C/h - Method B50 using a force of 50N and a heating rate of 50° C/h - Method A120 using a force of10 N and a heating rate of 120° C/h - Method B120 using a force of 50 N and a heating rate of 120° C/h. The methods specified are applicable only to thermoplastics, for which they give a measure of the temperature at which the thermoplastics start to soften rapidly.