Heat distortion temperature testing of plastics or HDT is a quality assurance test which complies with ASTM D648 and ISO 75 standards. It is utilized to evaluate the temperature at which a plastic or plastic composite specimen will deform under a given load. The heat distortion temperature is also termed as the ‘deflection temperature under load’ (DTUL) or ‘heat deflection temperature’ (HDT). These parameters are tested with the help of a proficient heat deformation tester.
Why is heat distortion testing required?
The properties of plastics like many materials depend on the factor of temperature. This takes on special importance for mechanically deformed parts, which are exposed to high temperatures. As a result of which, the heat distortion temperature property of a plastic material is of uppermost importance and has become a mandatory tool for product designing, engineering, and manufacturing, making the heat deformation temperature testing of plastics important.
Testing procedure
During the test, the plastic sample with pre-determined dimensions is placed into the testing apparatus. The sample direction based on the standard of ASTM or ISO, which is a very vital part of the entire test because it was found that it affects the result. Thus, a special attention should be taken while loading the sample in the correct position, as per the related standard. The fiber stress applied for the test is either 0.455 MPa or 1.82 MPa, and the temperature is raised at a rate of 2 °C/min until the specimen deforms up to 0.25 mm as per ASTM.
Testing Apparatus
Presto Heat Deformation – HDT/VSP Tester is utilized for determining the ability of a plastic to withstand load at elevated temperatures. It is designed as per standards of IS 2530-1963, ISO 75-1(2004)-E, ASTM D648-01, ASTM D1525-00.
Important features we deliver:
- 2 stations installed to measure deflection temperature and Vicat softening temperature at one place.
- Deliver precise measurement through digital dial gauge.
- Testing with both water and silicone oil is allowed.
- Highly advanced digital microprocessor PID based temperature controller.
- Obtain accurate test results under uniform temperatures inside the chamber.
- Made up of the strong rugged structure with corrosion resistant main body.
- Faster guiding mechanism with plunger rod.
- Offer single handed hassle-free
- Equipped with stirrer motor for precise stirring of sample inside the tank and to maintain the uniformity of temperature
