ASTM D3461-97(2012)

4.1 Asphalt and pitch do not go through a solid-liquid phase change when heated, and therefore do not have true melting points. As the temperature is raised, they gradually soften or become less viscous. For this reason, the determination of the softening point must be made by an arbitrary, but closely defined, method if the test values are to be reproducible.

4.2 This test method is useful in determining the consistency as one element in establishing the uniformity of shipments or sources of supply.

1.1 This test method covers the determination of the softening point of asphalt and pitch in the range from 50 to 180°C by the cup-and-ball apparatus, and gives results comparable to those obtained by Test Method D36.