COMMON GRAY IRON PARTS STRESS RELIEF ANNEALING SPECIFICATION COMPARISON TABLE
The determination of stress relief annealing temperature must consider the chemical composition of cast iron. When the temperature of ordinary gray cast iron exceeds 550°C, graphitization and granulation of some cementite may occur, which reduces the strength and hardness. When alloying elements are contained, the temperature at which cementite begins to decompose can be increased to about 650°C.
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