Effects of laser shock processing on mechanical properties of AZ91 magnesium alloy

PEI Xu; REN Ai-guo; GU Yong-yu; XU Ren-jun; YU Shui-sheng; ZHANG Yong-kang

doi:10.3969/j.issn.1001-3806.2010.04.032

In order to study the influence of laser shock processing(LSP) and different laser shock model on the mechanical properties of magnesium alloy,an AZ91 magnesium alloy specimen was processed with two beams of nonsuperimposed Nd:glass laser pulses.The surface morphology,with an oval spot distribution,was observed and analyzed after shock,and then the model was compared with the traditional model of single-point-superposition.The nano-hardness of the shocked and non-shocked region was measured with a triboindenter nano-indentation instrument,and the measured value was 1.59GPa and 1.47GPa respectively.The residual stress in the shocked region was measured with a X2350A X-ray strain instrument,and the stress was simulated by means of the finite element software ABAQUS.Both experimental and simulation results were in good agreement,and showed that there was high residual stress distribution,about-120MPa in the shocked region.The results show that the non-superposition of dual-beam mode can improve the shock efficiency.The LSP can improve the nano-hardness and mechanical properties of magnesium alloy and enhance its resistance to foreign objects damages and antifatigue properties.

Effects of laser shock processing on mechanical properties of AZ91 magnesium alloy

Corresponding author: ZHANG Yong-kang, ykzhang@ujs.edu.en

1. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China;

2. Victory Ceramics Science and Technology Co.Ltd., Yixing 214200, China

Received Date: 2009-06-16

Accepted Date: 2009-10-08

Available Online: 2010-07-25

Abstract: In order to study the influence of laser shock processing(LSP) and different laser shock model on the mechanical properties of magnesium alloy,an AZ91 magnesium alloy specimen was processed with two beams of nonsuperimposed Nd:glass laser pulses.The surface morphology,with an oval spot distribution,was observed and analyzed after shock,and then the model was compared with the traditional model of single-point-superposition.The nano-hardness of the shocked and non-shocked region was measured with a triboindenter nano-indentation instrument,and the measured value was 1.59GPa and 1.47GPa respectively.The residual stress in the shocked region was measured with a X2350A X-ray strain instrument,and the stress was simulated by means of the finite element software ABAQUS.Both experimental and simulation results were in good agreement,and showed that there was high residual stress distribution,about-120MPa in the shocked region.The results show that the non-superposition of dual-beam mode can improve the shock efficiency.The LSP can improve the nano-hardness and mechanical properties of magnesium alloy and enhance its resistance to foreign objects damages and antifatigue properties.

HTML

Reference (18)

[1]	THARUMARAJAB A,KOLTUN P.Is there an environmental advantage of using magnesium components for light-weighting cars[J].Journal of Cleaner Production,2007,15(11):1007-1013.
[2]	ZHANG J,ZHANG Z H.Magnesium alloys and the application[M].Beijing:Chemical Industry Press,2004:1-307 (in Chinese).
[3]	MORDIKE B L,EBERT T.Magnesium properties-applications-potential[J].Materials Science and Engineering,2001,A302(1):37-45.
[4]	ZHANG Y K,HU C L,CAI L,et al.Mechanism of improvement on fatigue life of metal by laser-excited shock waves[J].Appl Phys,2001,A72(1):113-116.
[5]	MONTROSS C S,WEI T,YE L,et al.Laser shock processing and its effects on microstructure and properties of metal alloys:a review[J].International Journal of Fatigue,2002,24(10):1021-1036.
[6]	FAN Y,WANG Sh B,WU H X,et al.Experimental research of laser shock processing on aerial aluminum alloy[J].Laser Technology,2003,27(4):273-275(in Chinese).
[7]	ZHANG Y K,ZHANG X Q,ZHOU J Zh,et al.Deformation of aluminum alloy LY12CZ plate by laser shot peening[J].Chinese Journal of Laser,2006,33(10):1417-1421.
[8]	GU Y Y,ZHANG X Q,SHI J G,et al.Investigation of inverse deformation in la ser shock forming with half die[J].Laser Technology,2008,32(1):95-97(in Chinese).
[9]	ZHANG Y K,CHEN J F,XU R J.Experimental research of laser shock strengthening AM50 magnesium alloy[J].Chinese Journal of Laser,2008,35(7):1068-1072(in Chinese).
[10]	ZHAO H L,CUI D G,GAO W,et al.Micromechanical properties estimation of composite coating consisting of cerium and titanium using nano-indentation technique[J].Journal of Materials Science and Engineering,2007,25(4):511-514(in Chinese).
[11]	YILBAS B S,ARIF A F M.Laser shock processing of aluminum:model and experimental study[J].J Phys,2007,D40(21):6740-6747.
[12]	ZHANG W W,LAWRENCE Y Y,NOYAN I C.Micro-scale laser shock peening of thin films,part 2:high spatial resolution material characterization[J].Journal of Manufacturing Science and Engineering,2004,126(1):18-24.
[13]	THORSLUND T,KAHLEN F J,KAR A.Temperatures,pressures and stress during laser shock processing[J].Optics and Laser in Engineering,2003,39(1):51-71.
[14]	PEYRE P,FABBRO R,MERRIEN P,et al.Laser shock processing of aluminum alloys.Application to high cycle fatigue behaviour[J].Material Science and Engineering,1996,A210(1):102-113.
[15]	ZHANG X Q,ZHOU J Zh,WANG G L,et al.Technology of laser peening and its application[J].Manufacturing Automation,2005,27(10):26-28(in Chinese).
[16]	ZHOU J Zh.Study on the mechanism of shock wave loading and the property of deformation of sheet metal of laser shock forming[D].Zhenjiang:Jiangsu University,2003:1-120(in Chinese).
[17]	CHEN J F.Study on laser surface modification of AM50 magnesium alloy[D].Zhenjiang:Jiangsu University,2008:1-109(in Chinese).
[18]	ZHOU N,QIAO D J.Materials dynamics under pulse beam radiation[M].Beijing:National Defense Industry Press,2002:1-159(in Chinese).

Effects of laser shock processing on mechanical properties of AZ91 magnesium alloy

Abstract

References

Proportional views

通讯作者: 陈斌, bchen63@163.com

Proportional views