Practical quantification of the effects of flow stress, friction, microstructural properties, and the tribological environment on macro- and micro-structure formation during hot forging

Abstract We present a practical approach that improves the accuracy of finite element predictions of hot forging; we emphasize the importance of tribological characterization. We analyze three-stage hot forging of high-strength S45C bearing steel in terms of metal flow lines sensitive to friction. An optimized friction condition is determined by comparing the predicted and experimental flow lines under various conditions. We use a phenomenological approach to predict grain size after dynamic recrystallization when investigating the effects of friction. We explored the relationship between macroscopic and microscopic phenomena with an emphasis on the tribological effect. Friction coefficient optimization improved the predicted metal flow lines and also reduced the error between predicted and measured grain sizes after dynamic recrystallization at all sample points.