ASTM D7735-17 PDF Download

The ASTM D7735-17 standard is a method used to measure the hardness of thermoplastic pavement marking material when exposed to high temperatures. The test is based on the penetration of a specific indentor into the material under specified conditions. The hardness is inversely related to the penetration and is influenced by factors such as the elastic modulus, viscoelastic behavior, indentor geometry, applied force, and test temperature.

It is important to note that this test method is empirical and primarily used for control purposes. There is no simple relationship between the measured hardness and any fundamental property of the material being tested. The standard emphasizes the need to maintain constant temperatures for both the test sample and the instrument.

This test method is considered similar to the Test Method D2240 for hardness, but with extra attention given to temperature control. Within the highway materials community, it is sometimes referred to as "indentation resistance." Additionally, all materials, instruments, and equipment used in the test must be traceable to the National Institute of Standards and Technology or other internationally recognized organizations.