Hardness tests on plastics
ISO 2039-1, ISO 2039-2, ISO 48-4, ISO 868, ASTM D2240, ASTM D785, ISO 19278
The plastics industry applies a variety of hardness testing methods, and each method addresses a different measurement objective. They can be in the nano, micro, or macro range.
Plastics brochure Test methods Shore ISO 48-4, ISO 868, ASTM D2240 Ball indentation ISO 2039-1 Rockwell ISO 2039-2/ASTM D785 Instrumented hardness testing ISO 19278 Videos Testing systems
Ball Indention Hardness ISO 2039-1
- Ball indentation hardness to ISO 2039-1 is used widely in European laboratories. A spherical indenter with a diameter of 5 mm is pressed into the plastic specimen at a constant test load. The indention depth under load is the determining variable for the hardness value. The standard defines a selection of test loads so that the indention depth is limited to a range of 0.15 mm to 0.35 mm.
- The high test loads and the deep indention allow for measurement across a large test surface and thus, a strong average of the measured value. This method is suitable for measuring both filled and unfilled plastics.
Rockwell hardness test ISO 2039-2, ASTM D785
- ISO 2039-2 and ASTM D785 define various Rockwell hardness scales for plastics testing.
- In contrast to ball indention hardness, in which the indention depth is measured under load, with the Rockwell method, the indention depth is measured at a defined preload. There are a variety of indenters available that correspond to the Rockwell scale.
Rockwell hardness testers
- Rockwell hardness testers from ZwickRoell feature an indenter-holder for hardness testing at difficult-to-access locations.
- Hardness testers in the ZHR product line cover the following methods:
- Regular Rockwell hardness testing (ZHR4150) to ISO 6508, ASTM E18 preload: 10 kg. Test load: 60, 100, 150 kg scales: A B C D E F G H K L M P R S V
- Superficial Rockwell methods (ZHR4045) to ISO 6508, ASTM E18 preload: 3 kg. Test load: 15, 30, 45 kg scales: N T W X Y
- Universal Rockwell (ZHR8150) to ISO 6508, ASTM E18 preload: 3, 10 kg. Test load: 15, 30, 45, 60, 100, 150 kg scales: A B C D E F G H K L M N P R S Y V W X Y
- Rockwell for plastics (LKP) to ISO 2039-2 and ASTM D785 (A&B)
