Ralph I. Stephens

Joined the College of Engineering: 1965 

Education: Ph.D., Engineering Mechanics, University of Wisconsin, 1965
M.S., Theoretical and Applied Mechanics, University of Illinois, 1960
B.S., General Engineering, University of Illinois, 1957

Special Fields of Knowledge: Fatigue; fracture mechanics; product liability. 

Present Research Interests: Computational/experimental dirt tack race car dynamics, Fatigue behavior of cast steel , Influence of high mean tensile stress on fatigue life, Influence of residual stress and mean stress on bolted and welded fasteners.

Selected Publications:

• Stephens, R.I., Fatemi, A., Stephens, R.R. and Fuchs, H.O., Metal Fatigue in Engineering, 2nd edition, Wiley Interscience, New York, 2000, (455 pages).
• Pals, T.J. and Stephens, R.I., "The Influence of High R Ration on Mild and Sharp Notched and Unnotched Fatigue Behavior of 1045 Steel with Three Different Heat Treatments," International Journal of Fatigue, Vol. 26, pp. 651-661, 2004.
• Sigl, K.M., Hardin, R.A., Stephens, R.I., and Beckermann, C., "Fatigue of 8630 Cast Steel in Presence of Porosity," International Journal of Cast Metals Research, Vol. 17, No. 3, pp. 130-146, 2004.
• Stephens, R.I., Bradley, N.J., Horn, J.J., Gradman, J.M., Arkema, J.M., and Borgwadt, C.S., " Fatigue of High Strength bolts Rolled Before or After heat Treatment with Five Different Preload Levels," SAE publication, 2005.
• Horn, N.J., and Stephens, R.I., "Influence of cold Rolling Threads Before or After Heat Treatment on High Strength Bolts for Different Fatigue Preload Conditions," Journal of ASTM International, 2005.

Active Scientific and Professional Society Memberships: Sigma Xi; Pi Tau Sigma; American Society of Testing and Materials, E08 on Fatigue and Fracture; Society of Automotive Engineers Fatigue Design and Evaluation; Registered Professional Engineer, State of Iowa.