What are some common standards for testing caster material embrittlement resistance?

Common standards for testing caster material embrittlement resistance primarily focus on the toughness, impact resistance, and structural stability of materials in low-temperature environments. The following are the core standards and their contents:

1. ASTM D256 (American Society for Testing and Materials Standard)
Test Type: Simple Beam Impact Strength Test.
Core Content: A caster material specimen (notched or unnotched) is placed at a specified low temperature (e.g., -20°C, -40°C) for at least 4 hours. A pendulum is then applied to the specimen, and the energy absorbed at fracture is measured (kJ/m²). The acceptance standard for embrittlement resistance is typically an impact strength of >5 kJ/m² for the notched specimen with no visible fracture.

2. ISO 179 (International Organization for Standardization Standard)
Test Type: Izod Beam Impact Test.
Core Content: An impact is applied to a notched specimen at low temperatures, and the energy absorbed per unit area is calculated. This is used to assess a material's resistance to fracture at low temperatures. Common requirements include an impact strength of ≥4 kJ/m² at -30°C, with no brittle fracture characteristics on the fracture surface.

3. GB/T 1843 (China National Standard)
Test Type: Plastic Izod Beam Impact Test Method.
Core Content: Simulates low-temperature operating conditions (e.g., -10°C, -25°C) by impacting the specimen with a pendulum. The failure type (ductile fracture/brittle fracture) and impact strength are recorded. Materials resistant to embrittlement must exhibit ductile fracture with an impact strength reduction of ≤30%.

4. Low-Temperature Bend Test (Industry Standard)
Test Content: After the material is allowed to stand at low temperature for 24 hours, a 90° or 180° bend test is performed to observe for cracks or fractures. To pass embrittlement resistance, no visible cracks must be observed, and structural integrity must be maintained.

These standards scientifically evaluate the low-temperature embrittlement resistance of caster materials by quantifying impact strength, observing fracture morphology, and structural stability, providing a basis for selection.