Fatigue Property Test and Numerical Simulation Analysis of 2524 Aluminum Alloy by Laser Shock Process

2020 ◽  
Vol 842 ◽  
pp. 265-271
Author(s):  
Song Bai Li ◽  
Xiang Li
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
Simulation Analysis ◽  
Laser Energy ◽  
Stress Test ◽  
Fatigue Properties ◽  
Laser Shock ◽  
Shock Process

Effects of laser shock peening on the fatigue properties of 2524 aluminum alloy were investigated by laser shock test, residual stress test and fatigue crack growth test respectively. The results show that the maximum residual stress is -220MPa at a distance of 1.1mm from the spot center after LSP (laser energy of 6.26J). The distribution of residual stress was simulated by Abaqus software, and the numerical simulation results were in good agreement with the experimental results. Compared with the untreated specimens, the fatigue life of the shocked specimens was increased by 32%. Fatigue fracture morphologies of the final rupture zone also show that more dimples of significantly larger depth and size occur. The fatigue life of 2524 aluminum alloy can be effectively extended by laser shock process (LSP).

The Fatigue Properties of Laser Shock Processed Aluminum Alloy 7050

2007 ◽  
Author(s):  
Shikun Zou ◽  
Ziwen Cao
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
Plastic Strain ◽  
Base Material ◽  
Fatigue Properties ◽  
Hole Drilling ◽  
Drilling Process ◽  
Laser Peening ◽  
Laser Shock

In order to develop the application of laser shock processing (also named laser peening or LSP in short) as a strengthening technology for 7050 aluminum alloy fastener holes, the fatigue properties of laser shock-processed aluminum alloy specimens were investigated. At first, the dislocation density and surface residual stress induced in the shock affected zone was characterized and compared with that of the base material. Then, the fatigue specimens with stress-concentration hole (notch) were treated by LSP. The fatigue life of LSP-treated specimens were measured and compared with that of specimens made from base material without LSP. Fatigue tests were taken under special flight spectrum loading condition for mid-airframe. The results indicated that laser peening improved the fatigue life of all specimens tested. Specimens treated by LSP before hole-drilling had longer fatigue life than those specimens treated by LSP after hole-drilling. At last, the difference of both sequences was investigated by analyzing the plastic strain and residual stress induced by LSP. LSP induced both plastic strain and deformation at the surface layer. The plastic strain induced by LSP was shown to produce harmful orifices with sharp-angle near the edge of hole. The residual stress induced by LSP appears to remain compressive even after the hole-drilling process. In average, the fatigue life of specimens treated by LSP before hole-drilling was found to be 173% longer than that of untreated samples and approaching the life enhancement factor demonstrated by rod extrusion method (on specimens with large diameter holes).

Numerical Simulation of Laser Shock Peening on Residual Stress Field of 7075-T6 Aluminum Alloy Welding

2014 ◽  
Vol 34 (4) ◽  
pp. 0414003
Author(s):  
罗密 Luo Mi ◽  
罗开玉 Luo Kaiyu ◽  
王庆伟 Wang Qingwei ◽  
鲁金忠 Lu Jinzhong
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Aluminum Alloy ◽  
Stress Field ◽  
Laser Shock Peening ◽  
Laser Shock ◽  
Residual Stress Field ◽  
Shock Peening

Numerical Simulation of Fatigue Life of 7050 Aluminum Alloy Processed by Laser Shock Processing

2010 ◽  
Vol 37 (12) ◽  
pp. 3192-3195 ◽  
Author(s):  
张洁 Zhang Jie ◽  
顾祥 Gu Xiang ◽  
祝乐 Zhu Le ◽  
孙爱华 Sun Aihua
Keyword(s):  
Numerical Simulation ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
7050 Aluminum Alloy ◽  
Shock Processing

Microstructure and Fatigue Properties of Aero Aluminum Alloy Repaired by Laser Melt Casting

2011 ◽  
Vol 314-316 ◽  
pp. 1871-1875 ◽  
Author(s):  
Chang Liang Lu ◽  
Fang You Hu ◽  
Xu Ren Huang ◽  
De Xian Yi ◽  
Ai Yong Cui ◽  
...  
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
Composite Powder ◽  
Crystal Size ◽  
Axial Direction ◽  
Fatigue Properties ◽  
Crystallographic Axis ◽  
Al Matrix Composite ◽  
Al Matrix

The paper presents a study of renovation of aerial aluminum alloy (LY12CZ) by laser melt casting with Al matrix composite powder. The microstructure of the melt casting zone was investigated, and the fatigue contrast test was carried out between the repaired specimens and the undamaged specimens. It is found that the melt casting zone consists of equiaxed crystals and columnar crystals. The equiaxed crystals distribute in the deposited layer and the crystal size is about 3~4μm. The columnar crystals whose axial direction size comes to 30μm~40μm exist near the interface with its crystallographic axis perpendicular to the interface. The fatigue life of specimens repaired by laser melt casting was shorter than no-damage specimens to a large extant, because of the flaws in the deposited layer engendered the origins of cracks; the columnar shape grains at the bottom of casting zone were easy to split under the tensile stress; the residual stress after the melt casting accelerated the initiation and growth of the cracks.

scholarly journals Improvement of Wear Resistance in Laser Shock-Peened Copper Contacts

2020 ◽  
Vol 58 (8) ◽  
pp. 560-565
Author(s):  
Donghyuck Jung ◽  
Changkyoo Park ◽  
Eun-Joon Chun ◽  
Yoon-Jun Kim
Keyword(s):  
Residual Stress ◽  
Wear Resistance ◽  
Energy Density ◽  
Laser Energy ◽  
Stress Test ◽  
Electrical Contact ◽  
Pure Copper ◽  
Surface Hardness ◽  
Laser Energy Density ◽  
Laser Shock

This study investigated the influence of laser shock peening without coating (LSPw/oC) on the degradation of copper electrical contacts. A theoretical calculation of the plastic-affected depth (PAD) induced by LSPw/oC was performed, based on the laser-induced plasma pressure along with the Hugoniot elastic limit of our LSPw/oC experimental conditions. The theoretical PAD was obtained approximately 650 µm from the surface for the LSPw/oC at the laser energy density of 5.3 GW/cm2. Various characterization methods such as the Vicker’s hardness test, residual stress test, and electron backscattered diffraction (EBSD) mapping indicated the PAD may play a significant role in laser induced effective depth for LSPw/oC. At a laser energy density of 5.3 GW/cm2, the laser shock-peened copper showed approximately double the surface hardness as compared to the pure copper. This was attributed to grain refinement, which was confirmed by measuring average grain sizes, and by observing mechanical twin structures from the EBSD analysis. Additionally, a compressive residual stress was induced down to the PAD but gradually switched to a tensile residual stress below PAD. The surface hardening effect conferred by LSPw/oC to the pure copper surface resulted in excellent wear resistance, i.e., a low coefficient of friction and wear loss. As a result, the contact exhibited lower electrical resistance following the fretting friction test compared to pure copper; this would result in a significant delay in electrical contact failure.

Effect of sand-blasting on fatigue properties of 7N01 aluminum alloy

2019 ◽  
Vol 33 (01n03) ◽  
pp. 1940003 ◽  
Author(s):  
Shali Qu ◽  
Min Yu
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
High Speed ◽  
Fatigue Properties ◽  
Sand Particle ◽  
Surface Zone ◽  
Sand Blasting ◽  
Depth Direction ◽  
High Speed Trains

Certain high-speed trains often suffer from the erosion of wind-drift sand during the serving period. The present paper simulated this sand-blasting process with consideration of sand-blasting pressure, angle, distance and sand particle size representing different natural conditions. Results show that the grit size has the greatest influence on roughness and residual stress of the 7N01 aluminum alloy based on the orthogonal test. The samples after low intensity sand-blasting (LISB) were characterized by micro-hardness, surface morphology and fatigue test. Results show that the surface of the blasted sample was severely impinged in form of extruded ridges crater-like morphology, representing different roughness values. The LISB causes a similar spoon shape residual stress distribution along the depth direction and it also increases the hardness of the surface zone. Finally, the residual compressive stress plays an important role in the improvement of the fatigue life, and the increase of roughness can seriously shorten the fatigue life.

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

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 59
Author(s):  
Hitoshi Soyama ◽  
Michela Simoncini ◽  
Marcello Cabibbo
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Fatigue Life ◽  
Compressive Residual Stress ◽  
Diffraction Method ◽  
Fatigue Properties ◽  
Surface Residual Stress ◽  
Friction Stir ◽  
Sheet Cavitation ◽  
Lightweight Metals

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 of Fatigue Life on MSC.Fatigue and ABAQUS

2010 ◽  
Vol 43 ◽  
pp. 624-627
Author(s):  
Jie Zhang ◽  
Xiang Gu ◽  
Hai Wei Ye ◽  
Kang Wen Li
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Finite Element ◽  
Fatigue Life ◽  
Fatigue Test ◽  
Surface Hardening ◽  
Laser Shock ◽  
Laser Shock Processing ◽  
Shock Processing ◽  
Important Significance

Laser Shock Processing (LSP) is a kind of new surface hardening technology, which can increase fatigue life obviously. Due to the LSP, the residual stress is generated and dislocations increase obviously in the surface of specimen, so the fatigue life of specimen processed by LSP increases. Thanks to the finite element programs, it is able to simulate the fatigue life. The simulation of fatigue life has important significance, which not only can reduce the costs of fatigue test and research, but also further study the effect of LSP on fatigue life. The results of fatigue test coincide with the results of simulation.

Sign in / Sign up

Export Citation Format

Share Document