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Softening point

The softening point is the temperature at which a material softens beyond some arbitrary softness. It can be determined, for example, by the Vicat method (ASTM-D1525 or ISO 306), Heat Deflection Test (ASTM-D648) or a ring and ball method (ISO 4625 or ASTM E28-67/E28-99 or ASTM D36 or ASTM D6493 - 11). A ring and ball apparatus can also be used for the determination of softening point of bituminous materials.

Usage examples of "softening point".

So my unit was set to heat the material to the softening point, so that it could be drilled.