The test is often used to specify appropriate materials for applications involving impact or to evaluate the effect of secondary finishing operations or other environmental factors on plastic impact properties. Test Procedure: The test sample rests on a base plate over an opening of specified diameter. An "impactor" sits on top of the test sample with a nose of specified radius in contact with the center of the test sample. A weight is raised inside a guide tube to a predetermined height, then released to drop onto the top of the impactor, forcing the nose through the test sample. The most common method to analyze this data is called the "Bruceton Staircase" method. Then a series of 20 impacts are conducted.
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This test consists of a fixed weight impacting a striker resting on top of a supported specimen dropped from various heights.
Click and Receive a quote within the next 4 hours. Use and factors to be considered for ASTM D When developing and selecting materials for specific applications, the knowledge of how the deformation of a polymer depends on their composition and structure is imperative.
The fluid and elastic properties of plastic or, better put, their viscoelasticity makes them sensitive to changes in weight velocities falling on their surface. Different polymers behave differently to changes in the velocity impact and it is crucial to be aware of their behavior. Typical Experimental parameters for ASTM D testing It is possible to use different striker diameters and specimen support plate geometries to obtain various types of failure.
The impactor head configuration H. The end use environment of the material shall be considered for the choosing but the selection of any other possibilities is permitted. If the latter is unknown, six or more additional specimens are necessary. Exposure temperature: Impact properties of polymers can be fairly sensitive to temperature. The specimen can be exposed at any reasonable temperature representing the end use conditions.
Relative humidity: Just like the temperature, the relative humidity shall represent the end use conditions as much as possible especially if the material tested is known to be hygroscopic. Width of flat test specimens: at least 25 mm 1 in. Should you need guidance in deciding which geometry or other elements should be used for your precise needs, feel free to contact us today.
Gardner Impact ASTM D4226, D5420