A Methodology for Finite Element Modeling Accurately Accounting for Case-Hardened Steel with Continually Varied Hardness Readings

Presented here is the finite element modeling of plate-structures within which mechanical properties varied dramatically from their outer surfaces towards inside cores. Developing such a model representing what can be characterized as laminates is of great significance in accurately predicting the strength. The benefits of this proposed methodology will be discussed by case studies of a centrifugal pendulum that has gained its popularity in high-end passenger cars because of its superior vibration suppression. The system in this work is subject to an excessive and destructive load due to centrifugal forces at extremely high angular velocities. It can be shown that the inner core, with much softer mechanical properties, easily gets into the plastic state and significantly restrains it from continuing to carry more loads as the angular velocity is ramped up. Consequently, the outer layers have to take an increased share of loads and their stresses are significantly raised. It is interesting to demonstrate that provided that the load is destructive and non-cyclic, it is the outer surface that would start to crack first, even if it has the highest tensile strength throughout the body. The proposed model has been found to be compared well with a test result in the load-carrying capability due to centrifugal forces.