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The Effects of Room Temperature Aging on Subsequent Bake-Hardening of Automotive Sheet Steels
Technical Paper
2002-01-0041
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Bake-hardening steels used for exposed auto-body panels provide low yield strengths before forming, and increased strength and dent resistance after the forming and paint-baking processes. Room temperature aging can alter the sheet properties before forming, after forming, or after baking. Knowledge of the evolution of mechanical properties is important, and the effects of room temperature and simulated room temperature aging (at 50°C and 100°C) on the yielding behavior and the bake hardening response of two different bake-hardening steel grades were studied. The steels included a low strength ultra-low carbon steel and a dual-phase steel with higher strength and greater bake-hardening index. Neither steel exhibited a substantial response to aging prior to tensile pre-straining, although both steels exhibited strength increases after either aging or baking following straining. The total strengthening increment was essentially independent of aging history for both steels, and followed t2/3 kinetics, with an apparent activation energy somewhat greater than the activation energy for carbon diffusion in ferrite.
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Citation
Wüebbels, T., Matlock, D., and Speer, J., "The Effects of Room Temperature Aging on Subsequent Bake-Hardening of Automotive Sheet Steels," SAE Technical Paper 2002-01-0041, 2002, https://doi.org/10.4271/2002-01-0041.Also In
References
- Shi M.F. et al. “Static and Dynamic Dent Resistance Performance of Automotive Steel Body Panels” SAE Technical Paper No. 970158 SAE Warrendale, PA 1997
- Matlock D.K. Allen B.J. Speer J.G. “Aging Behavior and Properties of Ultra-Low Carbon Bake-Hardening Steels Modern LC and ULC Sheet Steels for Cold Forming: Processing and Properties Bleck W. Verlag Mainz, Wissenschaftsverlag Aachen, Germany 1998 265 276
- Dahl W. et al. Eigenschaften und Anwendungen von Stählen I 5th Aachen, Germany 1998 183 217
- Baird J.D. Iron & Steel 1963 186 192 326 334 368 374 400 405
- Rosinger H.E. Metal Sci. 9 1 1975 1 7
- Wilson D.V. Acta Metall. 8 1960 468 479
- Cotrell A.H. Bilby B.A. Proc. Phys. Soc. London 1949 A62 49 49 69
- Indacochea E. Colorado School of Mines Golden, Colorado 1976
- Pradhan R. “Dent Resistant Bake-Hardening Steels for Automotive Outer-Body Applications” SAE Technical Paper No. 910290 SAE Warrendale, PA 1991
- Zaccone D. Michalak J.T. Elger J.A. Armitage J.R. “Characteristics of Box-Annealed Bake-Hardenable Steels” SAE Technical Paper No. 900714 SAE Warrendale, PA 1990
- Allen B.J. Matlock D.K. Sriram S. Speer J.G. “The Effects of Flow Stress on the Dent Performance of Sheet Steels” Proceedings of the 40 th Mechanical Working and Steel Processing Conference October 1998 ISS-AIME Warrendale, PA 1998 83 92
- Wert C.A. Phys. Rev. 79 1950 601