Low Pressure Carburizing and Hardening of AISI 9310: Merging Simulation and Experimental Approaches
摘要
Residual stresses and distortion induced during the heat treatment of carburized gears can significantly affect the mechanical properties and performance of the manufactured part. A carburizing and heat treatment process for AISI 9310 steel was simulated using the commercial finite element analysis package ABAQUS with DANTE Solutions add-in. The model was optimized based on experimental results, which included microstructural evaluation, hardness depth profile measurement, retained austenite measurement, and residual stress determination using the sin2ψ technique. Optimization of the model included consideration of the phase transformation kinetics, transformation temperatures, hardness for each phase, and elastic properties of each phase. There was a strong correlation among the effective case depth, the residual stress transition from compressive to tensile, and the drop in retained austenite to below 5% in the experimental results. The magnitude of the compressive hoop stress dropped from nearly 500 MPa after cryo-treatment to 400 MPa after tempering, and the extent of the compressive residual stresses shifted to greater depth after the tempering heat treatment step. The present work establishes a useful framework for model refinement, and the optimized model can be used in future parametric studies of heat treatment processing.