Introduction of iron casting furnace
White cast iron in casting furnace. The content of carbon and silicon is low, carbon mainly exists in the form of cementite, and the fracture surface is silvery white. The shrinkage during solidification is large, and it is easy to produce shrinkage cavities and cracks. High hardness and brittleness, unable to bear impact load. It is mainly used as the blank of malleable cast iron and manufacturing wear-resistant parts. Malleable cast iron. It is obtained by annealing white cast iron, and the graphite is flocculent, referred to as nodular cast iron.
Its structure and properties are uniform, wear-resistant, and have good plasticity and toughness. It is used to manufacture parts with complex shapes and can bear strong dynamic loads. Ductile iron. Gray cast iron is obtained by spheroidizing molten iron, and the precipitated graphite is spherical, which is called nodular cast iron for short. All or most of the carbon exists as spherical graphite in free state, and the fracture surface is silver gray. It has higher strength, better toughness and plasticity than ordinary gray cast iron.
Its brand number is represented by QT followed by two sets of numbers, such as QT45 to Qt 5. The first set of numbers represents the lowest tensile strength and the second set of numbers represents the lowest elongation. Used for manufacturing internal combustion engines, automobile parts and agricultural machinery. Vermicular graphite cast iron gray cast iron molten iron was obtained by vermicular treatment, and the precipitated graphite was wormlike.