Three-Dimensional FEM Analysis of Helical Gear Subjected to the Carburized Quenching Process
Manabu FUKUMOTO, Masatoshi YOSHIZAKI, Hideki IMATAKA, Kazuo OKAMURA and Kenji YAMAMOTO
Abstract:The simulation system to evaluate the deformation during the carburized quenching process is developed, using the commercial FEM code "ABAQUS". In this system, carburizing process and phase transformation kinetics are introduced by coding the constitutive relations into user subroutines available in ABAQUS, so as to simulate coupling effects of temperature, stress and metallic structure during the quenching process. And also, transformation plasticity and incomplete transformation of bainite are taken into account. For calculating phase transformations during continuous cooling, the additivity rule based on the isothermal transformation (IT) data is employed. If IT diagrams are not available enough to calculate transformation kinetics appropriately at any location of carburized work, they can be estimated from CCT diagram by a simple treatment proposed in this paper. The quenching process of Cr-Mo steel and Boron steel helical gear is studied with this system. The gear is partially modeled applying the cyclic symmetry constraint (MPC type CYCLSYM) in order to reduce the calculation time and to improve the accuracy. Calculated results are compared with the experimental measurements. Key Words:Carburized quenching, Phase transformation, ABAQUS, Incomplete transformation of bainite, IT diagram, Helical gear, Cyclic symmetry constraint