Charpy impact testing is conducted at -20°C to assess the ductility and toughness of materials under conditions that may lead to brittle failure. At lower temperatures, materials generally exhibit reduced ductility due to decreased atomic movement, while higher temperatures can enhance ductility and toughness due to increased atomic mobility. The recrystallization temperature is critical, as it influences the material's mechanical properties; below this temperature, materials tend to be more brittle. Conducting tests at higher temperatures may yield misleading results regarding a material's performance in cold environments. Understanding these temperature effects is essential for predicting material behavior in real-world applications.
