【国外标准】 Standard Test Method for Un-notched Cantilever Beam Impact Resistance (Izod Impact) Testing of Thermoplastic Pavement Marking Materials

5.1 The significance of this test is to determine the thermoplastic pavement marking material’s resistance to impact, under laboratory conditions. The method provides a numerical result for impact failure which can be used to assess quality and determine relative performance between materials.5.2 When the pendulum-impact test is performed on thermoplastic pavement marking materials, the results can indicate the strength and brittleness properties helpful in researching and improving their field durability. Anyone attempting to perform this test should initially review Test Methods D256 and Test Method D4812; especially the equipment setup.5.3 The following sample preparation and testing setup method is important so inconsistencies in sample preparation do not cause more inconsistency in the results that are inherent when testing thermoplastic pavement marking materials.1.1 This test method covers the sample preparation for cantilever beams and test methodology of thermoplastic pavement marking materials, similar to the “Izod Impact” method listed in Test Method D4812.1.1.1 Some methods call for results in inch pound-force (in.·lbf) as opposed to the common foot pound-force/inch (ft·lbf/in.) or Joule/meter (J/m) (energy absorbed per unit of specimen of similar cross-section). This method does not purport to cover all the issues involved with the pendulum impact of cantilever beams and suggests that Test Method D4812 and Test Methods D256 be reviewed before this methodology is attempted.1.1.2 Thermoplastic pavement marking materials are a highly filled polymer matrix. Depending on the formula the resulting matrix may be brittle, therefore possibly resulting in inconsistent test results.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.