Study on Residual Stresses Redistribution in Welded Joint in Shot peening process

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tudy on Residual Stresses Redistribution in Welded Joint in Shot peening process R. Moharrami R. Sourki p. Azadian Mechanical Engineering, University of Zanjan, Zanjan, Iran Mechanical Engineering, University of Zanjan, Zanjan, Iran Mechanical Engineering, University of Zanjan, Zanjan, Iran Abstract Investigations illustrate that fatigue behavior, corrosion resistance and failure behavior are one of the most common results affected by residual stresses. The shot peening process which causes compressive residual stress (CRS), is one of the ways to improve the performance of industrial components, especially weld joints with tensile residual stress. In the present paper, numerical analysis of parameters of shot peening process on residual stress distribution is employed on pre-stressed specimen. On one hand, the numerical simulation of this process is investigated. On the other hand, the surface CRS and the effective parameters of this process, by simulating it on the welded specimen, are investigated on and around the welding region. In each section, numerical results were verified not only with former numerical investigations but also with building a proper empirical specimen and measuring the stresses experimentally. Results illustrate the decrease of tensile residual stress or increase of CRS on the surface of the pre-stressed specimen after shot peening process. Moreover, it shows that parameters of the shot peening process have a significant impact on final stresses in the specimen. Besides, based on the results the maximum CRS goes up by increasing the diameter and velocity of the shot. Keywords: Residual stress, Redistribution, Simulation, Shot peening, weld joint. OA8 -N$ T< 1 230! :_ "3.% A $ RF ', 2&3"% ` @ 8% -))9 " [E 13 R M N$ Q> " K1F 03 &, 3C T< $$ 1 230 ' 2', 23"%.% b! KF, ]: 0 F a.18 QV13 9@% $$ 1 23 0 D" @ Q " % 23 * " B% 2$* 9@% 23 0!.' ))9 Q> 23 I3 23? " 9@% 2$* 1 0! ' 1>% * 1 0 2 8C -8@A & B% G> 2 -c d " * Q.' 9@% $$ >-1 9 23 "% #>X 1J 0<* 23? % " Y '! RZ 3 O% " " 2 +:, 2+ ))9 < "% G ))9 AN; -;E " ( ' W - % 1:; -))9.' * 3 $ ' 2" -( "! 3 "% " "% 28 2 ' * +( ) #(.' 1 23 0 " 7 -C/( Q 1; Y '!! 9@% $$ 1 230 0 #3 * Q " K1F. + " ' & $$ [ ",( 2+ " ' 230 9@% 1 2', 2\ " 8% ]^ :;.' $ ' * r_moharami@znu.ac.ir :

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B +( ( * $$ 1 23 0 2, ' ' 1>% 8@A UJ ( k -Y RZ 3 [ ' R9 UJ Q 8 x'.' $ +( % O:@ Q B 1 03M Q 2! $$ 9@% 1 230 2 ~@% 2 ' 1>% h! B < 2', RCF ~@% RZ T< -8@A 1; 0<* 8@A 9@% 0 2$* * $$ *. + +3&- [1] Handbook of Residual Stress and Deformation of Steel, ASM International, ISBN: 0-87170-729-2, 2002. [2] Schwarzer J., Schulze V., Vöhringer O., Finite Element Simulation of Shot Peening A Method to Evaluate the Influence of Peening Parameters on Surface Characteristics, Proceedings from International Conference of shot peening (ICSP-8), pp. 508-515, 2002. [3] Meguid S.A., Shagal G., Stranart J.C., Daly J., Threedimensional dynamic finite element analysis of shot-peening induced residual stresses, J. of F.E. in Analysis and design, Vol. 31, pp. 179-191, 1999. [] Rouhaud E., Oakka A., Ould C., Chaboche J., Francois M., Finite Elements Model of Shot Peening Effects of Constitutive Laws of the Material, Proceedings ICSP-9, pp. 107-112, 2005. [5] Shivpuri R., Cheng X., Mao Y., Elasto-plastic pseudo-dynamic numerical model for the design of shot peening process parameters, Materials and Design,Vol. 30, pp. 3112 3120,2009. [] Al-Hassani, Numerical Simulation of Multiple Shot Impact, Proceedings ICSP-7, pp. 217-227, 1999. [7] Zion H., Lewis, A Dynamic Finite Element Simulation of the Shot-Peening Process, [Ph.D. Thesis], USA, Georgia Institute of Technology, 2003. [8] Torres M.A.S., Voorwald H.J.C., An evaluation of shot peening, residual stress and stress relaxation on the fatigue life of AISI 30 steel, Int. J. of Fatigue, Vol. 2, pp. 877-88, 2002. [9] Hong T., Ooi J.Y., Shaw B., A numerical simulation to relate the shot peening process parameters to the induced residual stresses, Engineering Failure Analysis, Vol. 15, pp. 1097-1110, Paris, France, 2008. [10] Majzoobi G.H., Azizi R., Alavinia A., A three-dimensional simulation of shot peening process using multiple shot impacts, J. Material Process and Technology, pp. 1-15:122-3, 2005. [11] Miao H.Y., Larose S., Perron C., Levesque M., On the potential applications of a 3D random finite element model for the simulation of shot peening, Advances in Engineering software 0, pp. 1023-1038, 2009. [12] Kim T., J.H Lee J.H, Lee H., Cheong S.K., An area-average approach to peening residual stress under multi impacts using a three dimensional symmetry-cell finite element model with plastic shots, Material and Design, Vol. 31, pp. 50-59, 2010. [13] Azadiyan P., Experimental and numerical analysis of distribution of residual stresses caused by shot peening process on a welded specimen, M.Sc. Thesis, Department of Mechanical Engineering, University of Zanjan, Zanjan, 2011. (In Persian) [1] Guagliano M., Relating Almen intensity to residual stresses induced by shot peening: a numerical approach, J. Materials Processing Technology, Vol. 110, Issue 3, pp. 277 28, 2001. *-C&',3 U B?RQ'&) KFB^> ) Z3KF-3 1B ( " S 1>% -1/025-1/027 (*) ( " 0 1>% 0/9 (**) 0/9 L! L EF 2) 2; L (*).' 8 ]: 0 K, 1 230 (**). + 8@A % 1: 0 ) K8 0 K1; " ' 1 230 15 R' QV13 $ 1>% ( " ' 1 230 SX% $$ 0 1/027 B K8 $ 1>% ( " 8.% ' 0 ' kfn.% '! P@% 2 8@A ]:.% * 03 &, RA J 9@% $$ 1 *-C&',3 @' B?RQ./0( ),3?"W KF-15? (A8 L ) /@GQ /B &' /&]F-5! D" ' >% * 2"%' EF 2) 2 1 2 " 1>% * " '! 1 230.% ' % A RA A 1 0 ' 1>% * 23 2<% 75 # L % 2$* 1 0 R $$ 0 ) 03 8@A ]: 0 " R +' 0 +< 2 L " #13.' 500 300 )1; 0 28@A 2 1>% ( 2"%' ; % 0<* " 75 2$* 1 0 7 U1; +< 0<* - +< 231>% " B% QV13.% 1>% [8' 2$* 1 230 +< *!.J ' 1>% ".' 3( 9@% 1>% -:1; b! %! 2; L UJ * 9@% 2$* 1 230! R O% '.* 3( & ', -./ Y ' #( +( * 23 O% dh A b; -C QV13 UJ! K1F C 100 " 1 +' ' 1>%... ', K/ 1 230! D" % 192