Effect of ultrasonic nanocrystal surface modification on residual stress and fatigue cracking in engineering alloys

Khan, Muhammad Kashif; Fitzpatrick, M. E.; Wang, Hongtao; Pyoun, Young-Sik; Amanov, Auezhan

doi:10.1111/ffe.12732

Cited by 44 publications

(22 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An increase in the static load results in a deeper valley-depth as follows: 9.0 μm for 10 N, 11.1 μm for 30 N, and 11.2 μm for 50 N specimens. It suggested that valley depth may be associated with the intrinsic mechanical properties, such as yield strength and elastic modulus [21].…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

The Effect of the Static Load in the UNSM Process on the Corrosion Properties of Alloy 600

Kim

2019

Materials

View full text Add to dashboard Cite

To suppress stress corrosion-cracking, compressive residual stresses, such as shot peening, laser peening, water jet peening, ultrasonic peening, and ultrasonic nanocrystal surface modification (UNSM) are utilized. However, among the numerous techniques, there is little research about the corrosion effect of detailed conditions, such as static load or amplitude in UNSM. A study on UNSM among various techniques of adding compressive residual stress to Alloy 600 was conducted. The focus of this study was on the effect of the static load in UNSM on the corrosion properties of Alloy 600. Microstructure analysis was conducted using an optical microscope (OM), a scanning electron microscope (SEM), and electron backscattering diffraction (EBSD), while compressive residual stress was measured using a nano-indentation technique. A cyclic polarization test and the AC (Alternating Current)-impedance measurement were both used to analyze the corrosion properties. An increase in static load under critical static load enhanced the grain boundary diffusion, consequently strengthened the passive film, and facilitated the surface diffusion, thereby improving the passivation of Alloy 600. However, higher static loads over the critical value can lead to an increase in the friction between the striking tip and the surface, thereby creating an overlapped wave, which reduces the corrosion properties.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The plastic deformation produces a 1–2 mm deep compressive residual stress field in the material. The combination of surface deformation, the nanostructured layer, and compressive residual stresses causes a delay in fatigue crack initiation [21].…”

Section: Introductionmentioning

confidence: 99%

The Effect of the Static Load in the UNSM Process on the Corrosion Properties of Alloy 600

Kim

2019

Materials

View full text Add to dashboard Cite

show abstract

“…This difference is due to the different number of strikes. It is well established that the induced compressive residual stress is the most crucial property, which determines the strength and fatigue lifespan of a material [ 35 , 36 ]. It was also reported earlier that SP and USP processes induces high compressive residual stress in the surface layer thanks to the severe plastically deformed layer [ 11 , 34 ].…”

Section: Resultsmentioning

confidence: 99%

Gradient Nanostructured Tantalum by Thermal-Mechanical Ultrasonic Impact Energy

2018

View full text Add to dashboard Cite

Microstructural evolution and wear performance of Tantalum (Ta) treated by ultrasonic nanocrystalline surface modification (UNSM) at 25 and 1000 °C were reported. The UNSM treatment modified a surface along with subsurface layer with a thickness in the range of 20 to 150 µm, which depends on the UNSM treatment temperature, via the surface severe plastic deformation (S2PD) method. The cross-sectional microstructure of the specimens was observed by electron backscattered diffraction (EBSD) in order to confirm the microstructural alteration in terms of effective depth and refined grain size. The surface hardness measurement results, including depth profile, revealed that the hardness of the UNSM-treated specimens at both temperatures was increased in comparison with those of the untreated ones. The increase in UNSM treatment temperature led to a further increase in hardness. Moreover, both the UNSM-treated specimens with an increased hardness resulted in a higher resistance to wear in comparison with those of the untreated ones under dry conditions. The increase in hardness and induced compressive residual stress that depend on the formation of severe plastically deformed layer with the refined nano-grains are responsible for the enhancement in wear resistance. The findings of this study may be implemented in response to various industries that are related to strength improvement and wear enhancement issues of Ta.

show abstract

“…After calculation, we consider SSF ¼ 1:96 as the theoretical stress concentration factor of bolted joints. The crack propagation life of bolted joints at different test temperatures and stresses 37,38 are obtained by substituting related parameters into equation (20). The theoretical fatigue life of 2024 aluminum alloy joints are compared with the experimental data, 10 as shown in Table 6.…”

Section: Fatigue Life Analysis Of Plane Bolted Jointsmentioning

confidence: 99%

Numerical method for fatigue life of plane bolted joints under thermal load

You

Fang

Liu

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

In fatigue test, the fatigue life of metal components is affected by many factors, such as test temperature, stress ratio and loading frequency. In order to study the influence of temperature on fatigue life of bolted joints, thermal stress and fast coefficient are introduced. A numerical method of fatigue crack initiation life is proposed based on Manson-Coffin strain fatigue formula. The crack initiation life of 2024 aluminum alloy at different temperatures can be obtained by this method, which provides a theoretical basis for the fatigue life prediction of metals. Then, the stress severity factor SSF is introduced to calculate fatigue life of plane bolted joints. The data obtained from the model show that the crack initiation life of aluminum alloy specimen decreases significantly with test temperature rises, the same as the fatigue life of bolted joints.

show abstract

Effect of ultrasonic nanocrystal surface modification on residual stress and fatigue cracking in engineering alloys

Cited by 44 publications

References 23 publications

The Effect of the Static Load in the UNSM Process on the Corrosion Properties of Alloy 600

The Effect of the Static Load in the UNSM Process on the Corrosion Properties of Alloy 600

Gradient Nanostructured Tantalum by Thermal-Mechanical Ultrasonic Impact Energy

Numerical method for fatigue life of plane bolted joints under thermal load

Contact Info

Product

Resources

About