With the development and application of forgings, it is concluded that the deformation resistance of forgings is not only a function of metal chemical composition, deformation temperature, deformation degree and strain rate, but also related to the microstructure change of forgings during deformation.
The effect of chemical composition of forgings on pure metal, the higher the purity, the smaller the resistance to deformation. The influence of alloying elements on the deformation and resistance of forgings mainly depends on the properties of the interaction between atom and Matrix atom, the size of atomic radius and the distribution of the matrix. When a solid solution is formed by alloying elements in the matrix, the lattice distortion and the reinforcement effect are generated, and the deformation resistance of the forgings is increased, and if the alloying elements or impurities are dispersed in the grain boundary or crystal in the form of separate compounds, the amplitude of the deformation resistance can be improved. If impurities form brittle mesh inclusions, the deformation resistance decreases. In carbon steel, when the temperature is low, the deformation resistance of forgings increases with the increase of carbon content in steel, and the difference of deformation resistance is reduced at high temperature. With the increase of alloying element content, the deformation resistance is raised, and the trace elements in steel are added, such as Nb, Ti and V have a great influence on the deformation and resistance of the hot emulsion, and with the increase of the added amount of microelement, the deformation resistance of austenite increases, the action of Nb and Ti is larger, the effect of vanadium is smaller, and the cause of the increase of austenite deformation resistance is is due to the effect of trace elements in austenite and the effect of carbon or nitrogen precipitates in the form of NB (c, N), V (c, v), in which the precipitation is larger than that of the solid-soluble deformation resistance.