ASTM D1525 Vicat Softening Point of Plastics

The Vicat Softening Temperature (VST) of Plastics is determined by the Standard Method ASTM D1525.The sample is subjecte d to penetration by an indenting needle under load and controlled heating till the needle penetrates to 1 mm depth. The VST is reported in degrees Celsius.... Read More

  • Average 30% Cost

  • 100% Confidentiality

  • Free, No-obligation

  • 100% Customer



    The standard test method Vicat Softening Point of Plastics ASTM D1525, determines the softening temperature of thermoplastic polymers. Retention of mechanical strength and deformation resistance of plastics at elevated temperatures is a desired attribute in applications such as packaging and transport of hot fluids in plastic pipes. The VST is a key property in selecting plastics for elevated temperature applications. While the polymer suppliers’ technical data sheets would include VST data, independent testing is recommended for quality assurance. It may be noted that VST by the ASTM D1525 test method is not recommended for plastics that have a wide softening temperature range such as ethyl cellulose, flexible PVC and PVDC.

    Test Procedure:

    The ASTM D1525 VST test is performed by applying a specified, constant load onto an indenting needle which is placed upon the surface of the plastic test specimen. The test apparatus has a heating facility which subjects the loaded specimen to a controlled rate of temperature rise. The penetration depth of the needle into the specimen can also be precisely measured. The VST is the temperature at which the indenting needle penetrates to a depth of 1 mm. 

    Test equipment may have Oil bath or Dry heating facilities. The dry method mitigates safety concerns due to hot oil, in certain laboratory environments.

    Specimen size:

    The ASTM D1525 test specimens should be at least 10 mm square and between 3 mm and 6.5 mm thick. Larger sizes and thicknesses are acceptable, depending on the test equipment.


    The Vicat Softening Temperature is reported in 0C.


    ASTM D1525 is the standard test method for determining vicat softening temperature of plastic material.


    Core Materials Testing Services


    A variety of microscopy and spectroscopy tools available for precise measurements from the nano to the meter scale.

    Metrology Testing Services POPULAR TESTS:

    TEM SIMS Profilometry

    Materials Testing

    ASTM and ISO standard and custom chemical, mechanical, thermal, corrosion tests, etc. for all materials metals, ceramic or polymers.

    Materials Testing Services POPULAR TESTS:

    Nondestructive Testing Electrical Testing Chemistry Analysis

    Product Testing

    Thousands of tests for product quality and reliability under heat, humidity, temperature shock, vibration, drop, electrostatic discharge.

    Product Testing Services POPULAR TESTS:

    Vibration Testing Humidity Testing Accelerated Aging

    Looking for Material Testing?

    We have already delivered 10000+ Material Test results to top companies

      Send us a request

        Process for testing
          STEP 01

          You share material and testing requirements with us

          STEP 02

          You ship your sample to us or arrange for us to pick it up.

          STEP 03

          We deliver the test report to your email.

          Let’s work together!

          Share your testing requirements with us and we will be happy to assist you.

          ddd Just share your testing requirements and leave the rest on us!
          • Quick Turnaround and Hasslefree process
          • Confidentiality Guarantee
          • Free, No-obligation Consultation
          • 100% Customer Satisfaction


            Let us combine our capabilities to achieve success!!