Engineering and Technology Journal

Effect of Laser Shock Peening on Fatigue Stress Concentration of Polyester Reinforced by Al-Micro Powder Composites

Authors

1 University of Technology- Mechanical Eng. Dep., Baghdad, Iraq. dr_ahmed53@yahoo.com

2 University of Technology- Mechanical Eng. Dep., Baghdad, Iraq. ammar1199011@gmail.com

Abstract

Laser shock peening is a widely common process for materials treatment and typically used for fatigue strength enhancement especially for metals. In this paper, its effect on polymeric composite materials studied experimentally. Unsaturated polyester was used as a matrix in order to composites preparation and Aluminum powder as fillers. A Hand lay-up technique has been used for composites making. Composites with three volume fractions of Aluminum powder were prepared (2.5%, 5%, and 7.5%). Fatigue specimens as a standard and with (1mm) semi-circular notch are prepared for testing. The fatigue test was performed at room temperature and stress ratio (R=-1). Laser shock peening with two levels of energy have been applied (1Joule, and 2Joule). The results showed an increase in the endurance strength of the notch for 7.5% volume fraction especially at 1J laser energy by about 26.7056% compared with the un-treatment notched state, which in turn reduced the fatigue stress concentration by about 21.0508% compared with standard fatigue stress concentration. On the other hand, the presence of notch effect on endurance strength was increased after laser treatment of composites with 2.5% volume fraction and the reduced was by about 39.698% at 2J laser energy.

Keywords

References
 
[1]    I. M. Daniel and O. Ishai, “Engineering mechanics of composite materials,” New York Oxford, 1994.
[2]    Y. Murakami, “Metal fatigue: effects of small defects and nonmetallic inclusions,” Elsevier- Science Ltd, 2002.
[3]    M. R. Hill, A. T. DeWald, J. E. Rankin and M. J. Lee, “Measurement of laser peening residual stresses,” Journal of Materials Science and Technology, Vol. 21, Issue 1, pp.1-23, 2005.
[4]    A. J. Mohammed, “Effect of laser treatment on fatigue test for composite materials with presence of steel reinforcement,” The Iraqi Journal for Mechanical and Material Engineering, Vol.16, No.1, pp. 1-17, 2016.
[5]    A. N. Al-Khazraji and M. N. M. Shareef, “Comparison of fatigue life behavior between two different composite materials subjected to shot peening at different times,” Al-Khwarizmi Engineering Journal, Vol. 10, No. 3, pp. 1- 12, 2014.
[6]    A. T. Beyene, G. Belingardi and E. G. Koricho, “Effect of notch on quasi-static and fatigue flexural performance of T will E-glass/epoxy composite,” Elsevier- Composite Structures, Vol 153, pp. 825-842, 2016.
[7]    A. N. I. Al-Khazraji and T. A. H. AL-Taie, “The effect of shot peening on the notch sensitivity factor and neuber characteristic length for 7075-T6 aluminum alloy,” Journal of Engineering and Development, Vol.19, No.4, pp. 200- 218, July 2015.
[8]    M. Benedetti, V. Fontanari, B. Winiarski, P. J. Withers, M. Allahkarami and J. C. Hananc, “Fatigue behavior of shot peened notched specimens: effect of the residual stress field ahead of the notch root,” Elsevier- Procedia Engineering, Vol. 109, pp. 80-88, 2015.
[9]    J. E. Shigley and C. R. Mischke, “Standard handbook of machine design,” 2nd edition, McGraw-Hill Inc, 1996.
[10] R. S. Khurmi and J. K. Gupta “A textbook of machine design,” Eurasia Publishing House (PVT.) LTD, 2005.
[11] R. E. Peterson, “Stress concentration factor,” 2nd Edition, John Wiley & Son, 1997.
[12] M. N. M. Shareef, “Effect of shot peening on mechanical properties and endurance limit of composite materials,” M.Sc. Thesis, Mechanical engineering Department, University of Technology, Baghdad, Iraq, 2014.
[13] D. Hull “An introduction to composite materials,” University of Liverpool, Cambridge University, England, (1981).
[14] W.D. Callister, JR, "Materials science and engineering- an introduction" 6th Ed, John Wiely and Sons Inc, New York, (2003).
[15] N. P. Roberts and Nigel R. Hart "Alternating bending fatigue machine (HSM20),” Instruction Manual, Hi-Tech Ltd. UK. 2001.
[16] M. Tsuyama, Y. Kodama, Y. Miyamoto, I. Kitawaki, M. Tsukamoto and H. Nakano, “Effects of laser peening parameters on plastic deformation in stainless steel,” JLMN-Journal of Laser Micro/Nanoengineering Vol. 11, No. 2, pp. 227- 231, 2016.
[17] K. Ding and L.Ye, “Laser shock peening performance and process simulation,” Woodhead Publishing limited, Cambridge England, 2006.
[18] A. M. Mostafa, M. F. Hameed and S. S. Obayya “Effect of laser shock peening on the hardness of AL-7075 alloy,” Journal of King Saud University–Science, 2017, http://dx.doi.org/10.1016/j.jksus.2017.07.012.
[19] A. Azhari, S. Sulaiman and A. K. Prasada Rao, “A review on the application of peening processes for surface treatment,” IOP Conference Series: Materials Science and Engineering, Vol. 114, 2016.
Engineering and Technology Journal
Volume 38, 3A
March 2020
Page 325-334
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