Heat Treaters Conduct Distortion and Residual Stress Research
The Center for Heat Treating Excellence (CHTE) is working on research called Guidelines for Assessing Distortion and Residual Stress. According to Richard Sisson, George F. Fuller Professor of Mechanical Engineering and technical director of CHTE, this is an area of huge concern; companies spend millions of dollars scrapping parts that become distorted during the heat treat process, whether it’s during the heating up process or the cooling down. And some materials have stored residual stress, which causes distortion and compromises the integrity of the part.
Steve Ferdon, director of Engineering Technology, in the Fuel Systems Business at Cummins Inc., as well as a CHTE member and former chair of CHTE’s board of directors, is excited about this project. “Because residual stress and heat treat distortion are recurring frustrations for the industrial membership, we have had a truly open and collaborative effort to develop the objective and scope of work for this project, said Ferdon. “Global players in the aerospace, industrial equipment, transportation, automotive, heat treat equipment and Integrated Computational Materials Engineering (ICME) industries are engaged and will provide technical guidance and resources throughout the project. The expected outcome of this work will be the development of pre-competitive data, process design practices and analytical tools, that will have a real, practical and immediate benefit to members bottom lines.”
Key project objectives for the distortion and residual stress project include:
- Determining the most important heat treating process parameters that impact the residual stress and distortion in industrial parts.
- Developing a ranking of these processing parameters based on their impact.
- Providing processing guidelines to control residual stress and distortion.
The finite element (FE) model that combines a commercially available heat treatment software DANTE with the finite element analysis software ABAQUS has been used to identify the important heat treatment process parameters to control distortion and residual stress. The Ms temperature of the steel, the temperature dependence heat treatment coefficient of the quenching agent, quenching orientation, immersion speed, quenching temperature, austenitizing temperature and the part geometry are ranked based on their impact. The main purpose of this research is to provide processing guidelines to control residual stress and distortion.
To learn more about this distortion and residual stress research project or any of the other research CHTE is currently conducting, email: sisson@wpi.edu.