SG casting is a form of cast iron production where the graphite within the iron matrix is transformed into spherical nodules. This is achieved by adding magnesium-based alloys to molten iron under controlled conditions. The nodular graphite structure prevents crack propagation, significantly improving toughness, elongation, and fatigue resistance.

The manufacturing process at Sagar Foundry begins with the selection of high-grade raw materials, followed by controlled melting and chemical treatment. Molten metal is poured into engineered molds that allow complex shapes to be formed with high dimensional accuracy. Post-casting operations such as heat treatment, machining, and surface finishing further enhance performance and consistency.

This process results in a material that combines the castability of iron with mechanical properties close to steel.
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