Effect of forging temperature on homogeneity of microstructure and hardness of precision forged steel spur gear

Abstract Precision forging is a suitable process to produce spur gears due to its advantages such as reduction in machining time and production cost. The homogeneity in microstructure and mechanical properties of precision forging products can highly affect the performance of the gears during their service. In this research the effect of precision forging temperature on homogeneity of microstructure and hardness of forged gears of low carbon steel is studied. The microstructure and hardness map of the gears forged at a temperature range of 750–1150 °C revealed that the forging temperature of 950 °C is an optimum temperature to produce a spur five teeth gear with minimum inhomogeneity in the microstructure and hardness distribution.

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