Scatter Analysis of Fatigue Life and Pore Size Data of Die-Cast AM60B Magnesium Alloy
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 33041
Scatter Analysis of Fatigue Life and Pore Size Data of Die-Cast AM60B Magnesium Alloy

Authors: S. Mohd, Y. Mutoh, Y. Otsuka, Y. Miyashita, T. Koike, T. Suzuki

Abstract:

Scatter behavior of fatigue life in die-cast AM60B alloy was investigated. For comparison, those in rolled AM60B alloy and die-cast A365-T5 aluminum alloy were also studied. Scatter behavior of pore size was also investigated to discuss dominant factors for fatigue life scatter in die-cast materials. Three-parameter Weibull function was suitable to explain the scatter behavior of both fatigue life and pore size. The scatter of fatigue life in die-cast AM60B alloy was almost comparable to that in die-cast A365-T5 alloy, while it was significantly large compared to that in the rolled AM60B alloy. Scatter behavior of pore size observed at fracture nucleation site on the fracture surface was comparable to that observed on the specimen cross-section and also to that of fatigue life. Therefore, the dominant factor for large scatter of fatigue life in die-cast alloys would be the large scatter of pore size. This speculation was confirmed by the fracture mechanics fatigue life prediction, where the pore observed at fatigue crack nucleation site was assumed as the pre-existing crack.

Keywords: Fatigue life, Pore size, Scatter, Weibull distribution, Die-cast magnesium alloy

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1059573

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2381

References:


[1] Y. Lu, F. Taheri, M.A. Gharghouri, and H.P. Han, "Experimental and numerical study of the effects of porosity on fatigue crack initiation of HPDC magnesium AM60B alloy," J. Alloys Compd., vol. 470, pp. 202- 213, 2008.
[2] M.F. Horstemeyer, N. Yang, K. Gall, D. McDowell, J. Fan, and P. Gullet, "High cycle fatigue mechanisms in a cast AM60B magnesium alloy," Fatigue Fract. Engng. Mater Struct., vol. 25, pp. 1045-1056, 2002.
[3] B. Skallerud, T. Iveland, and G. Harkegard, "Fatigue life assessment of aluminum alloys with casting defects," Eng. Fract. Mech., vol. 44, pp. 857-874, 1993.
[4] Q.G. Wang, D. Apelian, and D.A. Lados, "Fatigue behavior of A356-T6 aluminum cast alloys. Part I. Effect of casting defects," J. Light Met., vol. 1, pp. 73-84, 2001.
[5] J.Z. Yi, P.D. Lee, T.C. Lindley, and T. Fukui, "Statistical modeling of microstructure and defect population effects on the fatigue performance of cast A356-T6 automotive components," Mater. Sci. Eng. A, vol. 432, pp. 59-68, 2006.
[6] J. Schijve, Fatigue of Structures and Materials, Springer, 2008, pp. 373- 393.
[7] H. El Kadiri, Y. Xue, M.F. Horstemeyer, J.B Jordan, and P.T. Wang, "Identification and modeling of fatigue crack growth mechanisms in a die-cast AM50 magnesium alloy," Acta Metall., vol. 54, pp. 5061-5076, 2006.
[8] M.F. Horstemeyer, N. Yang, K. Gall, D. L. McDowell, J. Fan and P. M. Gullett, "High cycle fatigue of a die cast AZ91E-T4 magnesium alloy," Acta Materialia, 2004, vol. 52, pp.1327-1336.
[9] C. Nyahumwa, N.R. Green, and J. Campbell, "Influence of casting technique and hot isostatic pressing on the fatigue of an Al-7Si-Mg alloy," Metall. Mater. Trans. A, vol. 32A, pp. 349-358, 2001.
[10] J.Z. Yi, Y.X. Gao, P.D. Lee, H.M. Flower, and T.C. Lindley, "Scatter in fatigue life due to effects of porosity in cast A356-T6 aluminum-silicon alloys," Metall. Mater. Trans. A, vol. 34, pp. 1879-1890, 2003.
[11] J. Schijve, "Statistical distribution functions and fatigue of structures," Inter. J. of Fatigue, vol. 27, pp. 1031-1039, 2005.
[12] W. Weibull, "A Statistical distribution function of wide applicability," J. Appl. Mech, 1951, vol. 18, pp. 293-297.
[13] X. Teng, H. Mae, Y. Bai, and T. Wierzbicki, Eng. Fract. Mech, 2009, "Pore size and fracture ductility of aluminum low pressure die casting," vol. 76, pp. 983-996, 2009.
[14] S.A. Khan, "Effect of anodized layer on fatigue behavior under humid environment," Ph.D. Thesis, 2007, pp. 5.1-5.17.
[15] J.C. Newman, JR., and I.S. Raju, "An empirical stress-intensity factor equation for the surface crack," Engineering Fracture Mechanics, Pergamon Press Ltd.,1981, vol. 15, No. 1-2, pp. 185-192.
[16] Y. Murakami, "Metal Fatigue: Effect of Small Defects and Nonmetallic Inclusions," Elsevier Science Ltd, Boston, MA, 2002, pp. 369.
[17] J.C. Ting, V. Frederick, and F.V. Lawrence, JR, "Modeling the long-life fatigue behavior of a cast aluminum alloy," Fatigue Fract. Eng. Mater. Struct., vol. 16, pp. 631-647, 1993.