The goal of heat treating is to improve in-service performance of steel components. For decades, heat treating has been based on experience. However, with computational power improving every year and computer hardware becoming less costly, simulation of complex processes and geometries is now feasible . Heat treatment processes are no longer a black box, but now have become transparent and malleable with the use of heat treatment software. Commercially available DANTE heat treatment software is used successfully to improve heat treat processes and steel part characteristics [1-3] as illustrated in the following examples in which real-world challenges were solved.
HEAT TREATMENT PROCESS MODELING
Modeling the heat treatment process requires the solution to several physical phenomena including:
* Mass diffusion for the carburization process
* Heat transfer for heating and cooling processes
* Stress and strain to predict deformation and residual stress
* Solid-state phase transformations to predict microstructural evolution
DANTE heat treatment simulation software accounts for all of these phenomena . The models in DANTE exist as libraries that link with commercial finite element packages ANSYS Mechanical and ABAQUS/STANDARD. The required material process data (defined as heat transfer coefficients as functions of part surface temperature) are contained in supplied databases.
EXAMPLE 1: PRESS/PLUG QUENCH TOOLING DESIGN
Problem. Press quenching of a carburized bevel gear was resulting in excessive radial shrinkage of the inner bore . Due to the carburized case on the inner bore spline teeth, final grinding could not be used to meet dimensional specifications and still meet mechanical property requirements.
Solution. DANTE was used to explore the effects of tooling constraints on radial shrinkage. Figure 1 shows the bevel gear and press quench tooling, further simplified to represent a single tooth. The assumptions of...