GB/T 9439-2023 standard specifies the technical requirements and test methods for gray cast iron parts. Gray cast iron is a cast iron material widely used in the industrial field. It has good casting performance and Mechanical Properties, and is often used in the manufacture of mechanical parts, auto parts, etc. This standard covers the chemical composition, mechanical properties, size and Appearance mass of gray cast iron parts, inspection methods, etc. By specifying the qualification standard, this standard aims to ensure the safety Reliability and mass Stability of gray cast iron parts in use, promote the standardization of the production process and the improvement of product mass.