HVT series of HDT/VICAT testing machine is mainly used to determine temperature of deflection under load and Vicat softening temperature of thermoplastic plastics, pipes and fittings.
Heat deflection temperature (HDT) (ISO 75, ASTM D648) indicates the relative behavior of different types of material under load at elevated temperatures. It is determined for materials such as thermoplastics, hard rubber and duroplastic laminates.
Vicat softening temperature (VST) (ISO 306, ASTM D1525) provides a value for the temperature at which a thermoplastic material begins to soften rapidly. This temperature is determined using a needle-shaped indenter with a round cross-sectional area of 1 mm?.