Speaker
Description
Carburised gears have been widely used in various mechanical transmission engineering fields. However, the carburising process is prone to mixed grain defects constraints on the carburising temperature further increase. Uneven distribution of grain will seriously damage the hardness, impact toughness and fatigue strength of gears and other key mechanical properties. The development of new energy vehicles and other fields of development for warm forging and other precision moulding gear requirements are becoming more and more stringent. Unfortunately, warm forging gears have a higher probability of occurrence of mixed grain. Different from the conventional precipitated particles regulation, we propose a new method for the design of precision-formed gear blanks based on the optimisation of deformation parameters. Firstly, we constructed the heat deformation constitutive equations applicable to the complete austenite and dynamic ferrite zones. Elucidated the dynamic changes of the grains under the warm forging condition. Secondly, by changing the shape of the billet, we accurately tailored the deformation gradient to achieve the reasonable optimization of the warm forging process. Lastly, by combining the finite element simulation with the industrial trial, we analyzed the grain evolution law of the whole process. It realized that the final gear finished product had an extreme difference in the grain size within 1.5 levels.