Ultrahigh dense and gradient nano-precipitates generated by warm laser shock peening for combination of high strength and ductility

Ye, Chang; Liao, Yiliang; Suslov, Sergey; Lin, Dong; Cheng, Gary J.

doi:10.1016/j.msea.2014.05.003

Cited by 100 publications

(40 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Juijerm's study shows that, during the plastic deformation process of AA 5083, high temperature leads to a much lower magnitude of compressive residual stress compared with room temperature, which is consistent with our study [21]. However, Ye et al claimed that WLP generates a higher magnitude of compressive residual stress than RT-LP for AA 7075 due to its effects on surface dislocation arrangement [18]. In fact, the generation mechanism of compressive residual stress on the aluminum alloy under high temperature is extremely complex.…”

Section: Residual Stress Distributionsupporting

confidence: 91%

“…However, there is a significant drop in hardness when the temperature reaches 130 • C. It can be concluded that 130 • C is the optimal temperature for the WLP of AA 6061-T6 from the perspective of precipitate strengthening. This is well consistent with Ye's conclusion [18]. It is concluded that, for a specific metal, an optimal temperature exists, if the WLP temperature exceeds the optimal one, the strengthening effect will decrease.…”

Section: Microhardnesssupporting

confidence: 90%

“…Our previous research verified WLP as an effective process to maintain more stable compressive residual stress on the surface of a treated Ti-6Al-4V alloy, resulting in better fatigue performance [16]. From the micro aspect, Ye's group observed some nanoscale precipitates in the WLP-treated AA 6061-T6 [17], and it is preliminary believed that these ultra-high-density nano-precipitates greatly improve the dislocation accumulation capacity and effectively increase the ductility of metals [18]. However, more convincing evidence and scientific data are required to validate the effectiveness of the WLP process on the surface properties.…”

Section: Introductionmentioning

confidence: 86%

“…However, Ye et al claimed that WLP generates a higher magnitude of compressive residual stress than RT-LP for AA 7075 due to its effects on surface dislocation arrangement [18]. In fact, the generation mechanism of compressive residual stress on the aluminum alloy under high temperature is extremely complex.…”

Section: Residual Stress Distributionmentioning

confidence: 99%

“…The highly tangled precipitate-dislocation interactions have relatively higher stability compared to dislocation structures without precipitates due to the beneficial pinning effect imposed by the precipitate particles. Ye's group employed HR-TEM to reveal that the precipitate particle is surrounded by high-density dislocations [18]. During plastic deformation, precipitate particles exert a pinning force to the dislocations nearby and thus increase the dislocation accumulation capacity.…”

Section: Microstructurementioning

confidence: 99%

See 4 more Smart Citations

Residual Stress Distribution and Microstructure Evolution of AA 6061-T6 Treated by Warm Laser Peening

Huang

Wang

Sheng

et al. 2016

Metals

View full text Add to dashboard Cite

Abstract:The aim of this paper is to study the effects of laser peening (LP) on the residual stress distribution and microstructure evolution of AA 6061-T6 under different temperatures. A laser peening experiment was conducted on the square-shape samples by using single spot and 50% overlap shock. Three-dimensional surface morphologies of treated samples were observed. The influence of peening temperature on the distribution of compressive residual stress was analyzed. An optical microscope (OM) and a transmission electron microscope (TEM) were employed to observe the microstructure evolution of the samples before and after LP. The results indicate that, as the peening temperature increases, the micro-hardness increases first and then decreases. The LP process induces high-amplitude compressive residual stress on the surface at different temperatures even if the compressive residual stress slightly reduces with increases in temperature. The maximum compressive residual stress affected layer depth is about 0.67 mm, appearing at a temperature of 160 • C. The OM test revealed that the grain size was significantly decreased after warm laser peening (WLP) and that the average value of grain size was reduced by 50%. The TEM test shows that more dislocation tangles were produced in AA 6061-T6 after WLP; compared to the LP process, the precipitate-dislocation interaction can benefit both strength and ductility for AA 6061-T6, thus enhancing the mechanical properties of the material.

show abstract

Section: Residual Stress Distributionsupporting

confidence: 91%

Section: Microhardnesssupporting

confidence: 90%

Section: Introductionmentioning

confidence: 86%

Section: Residual Stress Distributionmentioning

confidence: 99%

Section: Microstructurementioning

confidence: 99%

See 3 more Smart Citations

Residual Stress Distribution and Microstructure Evolution of AA 6061-T6 Treated by Warm Laser Peening

Huang

Wang

Sheng

et al. 2016

Metals

View full text Add to dashboard Cite

show abstract

Electrically Assisted Ultrasonic Nanocrystal Surface Modification of Ti6Al4V Alloy

Liu

Suslov

et al. 2017

Adv Eng Mater

View full text Add to dashboard Cite

In this study, an innovative process, electrically assisted ultrasonic nanocrystal surface modification (EA‐UNSM), is used to process Ti6Al4V alloy. As compared with traditional UNSM, EA‐UNSM results in lower dislocation density and larger grains due to the thermal annealing effect caused by resistive heating. In addition, deeper plastic deformation layer is observed in the electrically assisted case. By supplying mechanical energy and thermal energy simultaneously, a strong dynamic precipitation effect is induced, which generates nanoscale precipitates in the EA‐UNSM‐treated Ti6Al4V alloy. These nanoscale precipitates can effectively pin dislocations during plastic deformation and thus significantly improve the surface hardness.

show abstract

Effect of Laser Shock Peening on the Microstructures and Properties of Oxide‐Dispersion‐Strengthened Austenitic Steels

et al. 2017

View full text Add to dashboard Cite

Oxide-dispersion-strengthened (ODS) austenitic steels are promising materials for next-generation fossil and nuclear energy systems. In this study, laser shock peening (LSP) has been applied to ODS 304 austenitic steels, during which a high density of dislocations, stacking faults, and deformation twins are generated in the near surface of the material due to the interaction of laserdriven shock waves and the austenitic steel matrix. The dispersion particles impede the propagation of dislocations. The compressive residual stress generated by LSP increases with successive LSP scans and decreases along the depth, with a maximum value of À369 MPa. The hardness on the surface can be improved by 12% using LSP. In situ transmission electron microscopy (TEM) irradiation studies reveal that dislocations and incoherent twin boundaries induced by LSP serve as effective sinks to annihilate irradiation defects. These findings suggest that LSP can improve the mechanical properties and irradiation resistance of ODS austenitic steels in nuclear reactor environments.

show abstract

Ultrahigh dense and gradient nano-precipitates generated by warm laser shock peening for combination of high strength and ductility

Cited by 100 publications

References 39 publications

Residual Stress Distribution and Microstructure Evolution of AA 6061-T6 Treated by Warm Laser Peening

Residual Stress Distribution and Microstructure Evolution of AA 6061-T6 Treated by Warm Laser Peening

Electrically Assisted Ultrasonic Nanocrystal Surface Modification of Ti6Al4V Alloy

Effect of Laser Shock Peening on the Microstructures and Properties of Oxide‐Dispersion‐Strengthened Austenitic Steels

Contact Info

Product

Resources

About