Process Parameters Of Ductile Iron Manhole Cover

The mechanical properties of gray iron are related to the microstructure of the matrix and the morphology of graphite. The flaky graphite in gray cast iron severely cleaves the matrix, easily causing stress concentration at the sharp corners of the graphite, making the tensile strength, plasticity, and toughness of gray cast iron much lower than that of steel. However, its compressive strength is equivalent to that of steel, and it is also the cast iron with the worst mechanical properties among commonly used cast iron castings. At the same time, the matrix structure also has a certain impact on the mechanical properties of gray cast iron. The graphite flakes of ferrite matrix gray cast iron are coarse, with the lowest strength and hardness, so they are rarely used; The graphite flakes of pearlite based gray cast iron are small, with high strength and hardness, and are mainly used to manufacture more important castings; The graphite flakes of ferrite pearlite matrix gray cast iron are slightly thicker than pearlite gray cast iron, and their performance is not as good as pearlite gray cast iron. Therefore, gray cast iron with a pearlite matrix is commonly used in industry.