ISO 306-2013 pdf free download

ISO 306-2013 pdf free download.Plastics — Thermoplastic materials— Determination of Vicat softening temperature (VST)
Plastiques — Matières thermoplastiques — Determination de Ia tern pérature de rarnollissement Vicat (VST).
The temperature at which a standard indenting tip with a flat point penetrates 1 mm into the surface of a plastic test specimen is determined. The indenting tip exerts a specified force perpendicular to the test specimen, while the specimen is heated at a specified and uniform rate.
The temperature, in degrees Celsius, of the specimen, measured as close as possible to the indented area at 1 mm penetration, is quoted as the VST.
5 Apparatus
5.1 Heating equipment, consisting of one of the following (5jJ. J.I2 or j.13) that will accept a minimum of two test frame assemblies and a cooling device (L4).
The heating equipment shall be provided with means of temperature control, enabling the temperature
to be raised at a uniform rate 01(50 ± 5) K/h or (120 ± 10) K/h. The heating rate shall be verified
— either by checking and recording automatically over the whole temperature range, or
— by manually checkingand recording the temperature change at 6-mm intervals over the temperature range being verified.
The requirement for the heating rate shall be considered satisfied if. over every 6-mm interval during the test, the temperature change is (5 ± 0,5) °C or (12 ± 1) °C, respectively. For multiposition heating equipment, the heating rate shall be verified at each test station. The apparatus may be designed to shut off the heat automatically and sound an alarm when the specified indentation has been reached.
5.1.1 Liquid-fIlled heating bath, containing a liquid in which the test specimen can be immersed to a depth of at least 35 mm. Liquid paraffin, transformer oil, glycerol and silicone oil are suitable liquid heat- transfer media, but other liquids may be used. An efficient stirrer shall be provided. It shall be established that the liquid chosen is stable at the temperature used and does not affect the material under test, for example by swelling or cracking. Do not heat the liquid filled heating bath in excess of the flash point specified by the heat transfer media manufacturer.
5.1.2 Direct-contact heating unit, containing heaters and blocks, which through conductive heating. raise the temperature of the specimen at a controlled rate until the VST is reached.
5.1.3 Fluidized bed, containinga powderbed (e.g. aluminium oxide powder), in which the testspecimen can be immersed to a depth of at least 35 mm. This type of apparatus uses a micrometric aluminium oxide powder, which when mixed with a suitable flow of heated air, creates a liquid-like heating medium.ISO 306-2013 pdf free download.