VICAT SOFTENING TEMP. (ASTM D1525) : ❖ Determination of the temperature at which a standard indenter penetrates. ❖ 1mm into the surface of a plastics test specimen under one of the loads. ❖ specified under uniform rate of heating. ❖ Rate of rise of temp. 50 + 50C / per hr. 120 + 120C DEFLECTION TEMPERATURE OF PLASTIC UNDER FLEXURAL LOAD ( As per ASTM D-648) Determination of temp. at which an arbitrary deformation occurs when plastics are subjected to arbitrary bending loads and conditions of continually rising temperature. Rate of rise of temp. 2 + 0.20C / per min. VST/HDT PLC BASED ASTM D15425 & ASTM D648 Values of VST & HDT are obtained through software. Graphic display and printout through your PC: Penetration/ Deflection Vs Temperature graph and values of VST and HDT could br obtained by attaching a printer to the PC.