Effect of Cavitation Peening on Fatigue Properties in Friction Stir Welded Aluminum Alloy AA5754

Abstract

Friction stir welding (FSW) is an attractive solid-state joining technique for lightweight metals; however, fatigue properties of FSWed metals are lower than those of bulk metals. A novel mechanical surface treatment using cavitation impact, i.e., cavitation peening, can improve fatigue life and strength by introducing compressive residual stress into the FSWed part. To demonstrate the enhancement of fatigue properties of FSWed metal sheet by cavitation peening, aluminum alloy AA5754 sheet jointed by FSW was treated by cavitation peening using cavitating jet in air and water and tested by a plane bending fatigue test. The surface residual stress of the FSWed part was also evaluated by an X-ray diffraction method. It was concluded that the fatigue life and strength of FSWed specimen were improved by cavitation peening. Whereas the fatigue life at σa = 150 MPa of FSWed specimen was about 1/20 of the bulk sheet, cavitation peening was able to extend the fatigue life of the non-peened FSW specimen by 3.6 times by introducing compressive residual stress into the FSWed part. This is the first paper to demonstrate the improvement of fatigue properties of FSWed metallic sheet by cavitation peening.

Numerical Simulation and Process Study on Laser Shock Peening of 1Cr18Ni9Ti Material

“…The greater the roughness, the more significant the decrease in the fatigue life is [11]. Many experts in this field have also confirmed that laser shock peening improves the fatigue limit of various different materials [12][13][14][15].…”

Assessing Cavitation Erosion on Solid Surfaces Using a Cavitation Jet Apparatus

“…A cavitação é um fenômeno complexo que abrange aspectos hidrodinâmicos e materiais, conhecido por levar a consequências desastrosas, como a erosão por cavitação. (Arabnejad et al, 2020;Franc & Michel, 2006;Genovez & Dalfré Filho, 2008;Gualtieri & Chanson, 2021;Peng et al, 2020;Soyama et al, 2020). Hidrodinamicamente, envolve a formação de bolhas de vapor em regiões de baixa pressão de fluxo cavitante, que colapsam violentamente ao entrar em áreas de recuperação de pressão, resultando na erosão de superfícies sólidas.…”

“…Hidrodinamicamente, envolve a formação de bolhas de vapor em regiões de baixa pressão de fluxo cavitante, que colapsam violentamente ao entrar em áreas de recuperação de pressão, resultando na erosão de superfícies sólidas. (Arabnejad et al, 2020;Franc & Michel, 2006;Genovez & Dalfré Filho, 2008;Gualtieri & Chanson, 2021;Peng et al, 2020;Soyama et al, 2020). Fisicamente, a erosão por cavitação é caracterizada pela perda de material devido a colapsos agressivos de cavidades perto de superfícies, submetendo as superfícies adjacentes a altas cargas mecânicas e níveis de tensão que ultrapassam o rendimento do material ou a tensão de fadiga, levando, em última análise, à remoção de material.…”

Performance Analysis of 7075 Aluminum Alloy Strengthened by Cavitation Water Jet Peening at Different Scanning Speeds

“…Soyama et al first investigated the cavitation water jet in terms of improving the surface performance of parts and components and found that the residual compressive stress on the surface of parts and components after a cavitation water jet treatment has been significantly improved. Since then, the application of shot peening to the surface treatment of materials has become more and more extensive [14][15][16]. Hutli et al verified that the cavitation water jet is an effective method to improve the surface properties of materials, and the force generated by the cavitation can change the surface roughness of materials on the nanoscale and micron scale [17,18].…”