Q&A

We have provided illustrations of the following test methods for the test items that we receive the most questions about. Please click on the links below to view them. The information provided here is simplified. For more detailed information, please refer to the individual original standards.

About ISO test methods

The test method is introduced diagrammatically below. For detailed test methods, please refer to the original ISO test method.

• Charpy impact strength --- ISO 179
• Tensile yield stress, tensile modulus --- ISO 527
• Flexural strength, flexural modulus --- ISO 178
• Deflection temperature under load - ISO 75
• Melt Volume Flow Rate (MVR) - ISO 1133

Charpy impact strength ISO 179

The back side of the notch in the test piece is struck with a hammer, and the impact strength is evaluated based on the energy required to break the test piece.

・Test piece dimensions (mm) Thickness x width x length: 4 x 10 x 80 ・Distance between test pieces: 62mm Notch 45°, 2mm deep ・Unit: kJ/m2

Tensile Yield Stress and Tensile Modulus ISO 527

The specimen is subjected to tension at a grip of 115 mm, and the displacement and strength are measured. The tensile modulus is calculated in the region where the linear relationship between displacement and strength is established, and the tensile yield stress is calculated from the strength at the yield point.

・Test piece dimensions (mm) ------------------------- External total length x total width: 150 or more x 20 Test section thickness x width x length: 4 x 10 x 80 ------------------------- Test speed Tensile yield stress: 50mm/min. Tensile modulus: 1mm/min. ・Unit: MPa

Flexural strength and flexural modulus ISO 178

The strength associated with the displacement of the indenter at the center of the test piece is measured, and the elastic modulus is determined in the region where a linear relationship between displacement and strength is established. The bending strength is calculated from the strength at the yield point.

 

・Test piece dimensions (mm) Thickness x width x length: 4 x 10 x 80 ・Support distance: 64mm Test speed: 2mm/min. ・Unit: MPa

Deflection temperature under load ISO 75

The temperature at which a test piece in a liquid heat transfer medium begins to soften and reaches a specified deflection when the temperature is raised under bending stress. We measure this using the "flatwise" method as shown in the diagram below.

 

・Test piece dimensions (mm) Thickness x width x length: 4 x 10 x 80 Load and temperature conditions Bending stress: 1.80MPa Support distance: 64 mm Heating rate: 120℃/hr. ・Specified deflection: 0.32mm deflection ・Unit: ℃

Melt Volume Flow Rate (MVR) ISO 1133

The molten resin is extruded from the die under constant temperature and load. The amount of resin discharged in 10 minutes is measured and used as an index of the resin's fluidity.

 

・Test data: Dry pellets ・Measurement conditions Temperature: 220℃ : 230℃ (Some heat-resistant and alloy grades) Heating rate: 120℃/hr. Load capacity: 10kg ・Unit: cm3/10min.