ISO SN EN ISO 306 pdf download

ISO SN EN ISO 306 pdf download Plastics – Thermoplastic materials – Determination of Vicat softening temperature (VST) (ISO 306:2013)
1 Scope
This International Standard specifies four methods for the determination of the Vicat softeningtemperature (VST) of thermoplastic materials:
method A50 using a force of 10 N and a heating rate of 50 K/h;
method B50 using a force of 50 N and a heating rate of 50 K/h;
method A120 using a force of 10 N and a heating rate of 120 K/h;
method B120 using a force of 50 N and a heating rate of 120 K/h.
The methods specified are applicable only to thermoplastics, for which they give a measure of thetemperature at which the thermoplastics start to soften rapidly.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and areindispensable to its application. For dated references, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (including any amendments) applies.
ISO 291, Plastics – Standard atmospheres for conditioning and testing
ISO 293, Plastics — Compression moulding oftest specimens ofthermoplastic materials
SO 294-1, Plastics – Injection moulding oftest specimens of thermoplastic materials — Part 1: Generalprinciples, and moulding ofmultipurpose and bar test specimens
SO 294-2, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 2: Smalltensile bars
ISO 294-3, Plastics – lnjection moulding oftest specimens ofthermoplastic materials – Part 3: Small plates
ISO 472, Plastics – Vocabulary
ISO 2818, Plastics – Preparation oftest specimens by machining
ISO 20753, Plastics – Test specimens
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472 and the following apply.3.1
penetrationdistance over which the indenting tip has to penetrate into the specimen under test
Note 1 to entry: It is expressed in millimetres (mm).
3.2
load
force applied to test specimen by means of the indenting tip
Note 1 to entry: It is expressed in Newtons (N)
3.3
Vicat softening temperature
VST
temperature at which a flat-ended needle penetrates the specimen to a depth of 1 mm under a specifiedload using a selected uniform rate of temperature rise
Note 1 to entry: It is expressed in degrees Celsius (°C)
4 Principle
The temperature at which a standard indenting tip with a flat point penetrates 1 mm into the surface ofa plastic test specimen is determined. The indenting tip exerts a specified force perpendicular to the testspecimen, 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 areaat 1 mm penetration,is quoted as the VST
5 Apparatus
5.1 Heating equipment, consisting of one of the following (5.1.1 512 or 51.3) that will accept aminimum of two test frame assemblies and a cooling device (5.1.4).
The heating equipment shall be provided with means of temperature control, enabling the temperatureto be raised at a uniform rate of (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
bymanually checking and recording the temperature change at6-minintervals over the temperaturerange being verified
The requirement for the heating rate shall be considered satisfied if, over every 6-min interval duringthe test, the temperature change is (5 + 0,5) °C or (12 + 1) C, respectively, For multiposition heatingequipment, the heating rate shall be verified at each test station. The apparatus may be designed to shutoff the heat automatically and sound an alarm when the specified indentation has been reached.