Laser Peening on Aluminum Alloy 7049 Using Black Paint Surface Coating

• Main Authors: H. J. M. Alalkawi, Basim A. Sadkhan, Noor N. Abed
• Format: Article
• Language: English
• Published: Al-Khwarizmi College of Engineering – University of Baghdad 2015-06-01
• Series: Al-Khawarizmi Engineering Journal
• Subjects: Keywords: Constant and variable fatigue behavior , Black paint laser peening , 7049 Al- alloy .
• Online Access: http://alkej.uobaghdad.edu.iq/index.php/alkej/article/view/254

Abstract Black paint laser peening (bPLP) technique is currently applied for many engineering materials , especially for aluminum alloys due to high improvement in fatigue life and strength . Constant and variable   bending fatigue tests have been performed at RT and stress ratio R= -1 . The results of the present  work observed that the significance of the surface work hardening which generated high negative residual stresses in bPLP specimens .The fatigue life  improvement factor (FLIF)  for bPLP constant fatigue behavior was from 2.543 to 3.3 compared to untreated  fatigue and the increase in fatigue strength at 107 cycle was 21% . The bPLP cumulative fatigue life behavior was improved by 1.786 at L-H and 1.55 at H-L due to black paint coating .  Keywords: Constant and variable fatigue behavior , Black paint laser peening , 7049 Al- alloy .