Abstract
Casting durability may be assessed by several methods. In industrial powertrain castings engineering design is linked to the assessment of casting properties in particular high cycle fatigue performance. In the past porosity has been shown to be the most deleterious microstructural constituent in Al-Si cast alloys. Porosity is nucleated by oxide biflims and evolves during solidification due to segregated hydrogen gas and/or liquid feeding difficulties in the mushy zone during solidification. Porosity and oxide films have been reported to control casting durability as assessed through the fatigue staircase and calculated −3σ plots.
The authors will show in this work that grain structure can also play a major role in terms of controlling fatigue life. Specifically the presence of columnar grains in non grain refined casting structures can lead to low and unpredictable fatigue lives. The mechanisms of fatigue failure due to grain structure are reviewed and the use of grain refiner (in-mold process) to improve fatigue performance and counteract undesirable structure are discussed.
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References
J. E. Gruzleski & B. M. Closset, The Treatment of Liquid Aluminum-Silicon Alloys, American Foundry Society, Inc., 1990, 256pp, 1990.
Aluminum Casting Technology, Revised by J. L. Jorstad, W. M. Rasmussen, Edited by D. L. Zalensas, 2nd Ed., American Foundry Society, Inc., 201pp, 1993.
Q. S. Hamed, M. Dogan & R. Elliot, “The Dependence of Secondary Dendrite Arm Spacing on Solidification Conditions of Al-7Si-0.5Mg Alloys Treated with TiBAl and TiBAl/Sr Additions”, Cast Metals, Vol. 6, Number 6, pp. 47–53, 1993.
F. Paray & J. E. Gruzleski, “Microstructural-Mechanical Property Relationships in a 356 Alloy, Part 1: Micro structure” Cast Metals, Vol. 7, Number 3, pp. 29–40, 1994.
F. Paray & J. E. Gruzleski, “Microstructural-Mechanical Property Relationships in a 356 Alloy, Part 2: Mechanical Properties” Cast Metals, Vol. 7, Number 3, pp. 153–163, 1994.
F. Paray & J. E. Gruzleski, “Factors to Consider in Modification”, AFS Transactions, Vol. 102, pp. 833–842, 1994.
E. L. Rooy, “Mechanisms of Porosity Formation in Aluminum”, Modern Casting, pp. 34–36, Sept. 1992.
G. Byczynski and J. Campbell, “A study of crack initiation sites in high cycle fatigue of 319 aluminum alloy castings”, Shape Casting: The John Campbell Symposium, TMS (The Minerals, Metals and Materials Society), 2005, p. 235–244.
Couper, M. J., A. E. Neeson, et al. (1990). “Casting defects and the fatigue behaviour of an aluminium casting alloy.” Fatigue and Fracture of Engineering Materials and Structures 13(3): 213–227.
Skallerud, B., T. Iveland, et al. (1993). “Fatigue life assessment of aluminum alloys with casting defects.” Engineering Fracture Mechanics 44(6): 857.
Dixon, W. J. and A. M. Mood (1948). “A method for obtaining and analyzing sensitivity data.” Journal of the American Statistical Association 43(241): 109–126.
Brownlee, K. A., J. L. Hodges, et al. (1953). “The up-and-down method with small samples.” Journal of the American Statistical Association 48(262): 262–277.
J. Campbell, “Entrainment defects”, Materials Science and Technology, vol. 22, pp. 127–145, Feb 2006.
J. Campbell, “An Overview of the Effects of Bifilms on the structure and Properties of Cast Alloys”, Metallurgical and Materials Transactions B-Physical Metallurgy and Materials Science, vol. 37B, pp. 857–863, 2006.
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Byczynski, G., Mackay, R. (2014). The Effect of Grain Structure on Casting Durability Assessment in Al-Si Alloys. In: Tiryakioğlu, M., Campbell, J., Byczynski, G. (eds) Shape Casting: 5th International Symposium 2014. Springer, Cham. https://doi.org/10.1007/978-3-319-48130-2_28
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DOI: https://doi.org/10.1007/978-3-319-48130-2_28
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