A review of the effects of cyclic contact loading on fretting fatigue behavior

A damage phenomenon called fretting fatigue frequently takes place when two contact bodies are clamped together under a normal contact load along with a small-scale oscillatory motion due to cyclic loading. In contrast to the constant contact loading, less attention has been paid to variable contact loading which was technically reviewed in this study. Emphasis was placed on the efforts made over the past decade and the future challenges including nonlinear effects of contact loads, friction, frequency, slip amplitude, wear, and contact mechanic are discussed extensively. It was revealed a need for new fatigue and contact mechanics models by identifying the aforementioned missing parameters.

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EFFECT OF CONTACT PRESSURE ON FRETTING FATIGUE BEHAVIOR UNDER CYCLIC CONTACT LOADING

Surface Review and Letters ◽

10.1142/s0218625x18500324 ◽

2017 ◽

Vol 24 (Supp02) ◽

pp. 1850032

Author(s):

F. ABBASI ◽

G. H. MAJZOOBI

Keyword(s):

Fatigue Life ◽

Contact Pressure ◽

High Cycle Fatigue ◽

Fe Simulation ◽

Fatigue Behavior ◽

Fretting Fatigue ◽

Contact Load ◽

Normal Contact ◽

Contact Loading ◽

Crack Initiation Life

In this study, the effect of contact pressure on fretting fatigue behavior of Al7075-T6 under cyclic normal contact loading is investigated. It is found that fretting fatigue life for the case of cyclic contact load was significantly less than that for constant contact load at the same axial and contact load levels, particularly for High Cycle Fatigue (HCF) conditions. The results showed that the fretting fatigue life decreased monotonically with the increase in normal contact load for all axial stresses. Examination of the fretting scars was performed using optical microscopy and numerical simulation was carried out using commercial finite element (FE) codes ABAQUS[Formula: see text] and FRANC2D/L[Formula: see text] to calculate the crack propagation life. The crack initiation life was calculated by a combination of numerical and experimental results. Finally, the FE simulation was validated by a comparison between the numerical crack growth rate and the experimental measurement using replica.

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On the effect of shot-peening on fretting fatigue of Al7075-T6 under cyclic normal contact loading

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2017.08.067 ◽

2017 ◽

Vol 328 ◽

pp. 292-303 ◽

Cited By ~ 15

Author(s):

G.H. Majzoobi ◽

F. Abbasi

Keyword(s):

Shot Peening ◽

Fretting Fatigue ◽

Normal Contact ◽

Contact Loading

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Study on bending fretting fatigue damage in 17CrNiMo6 steel

International Journal of Modern Physics B ◽

10.1142/s0217979217440209 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744020 ◽

Cited By ~ 1

Author(s):

J. F. Peng ◽

X. Jin ◽

Z. B. Xu ◽

Z. B. Cai ◽

X. Y. Zhang ◽

...

Keyword(s):

Fatigue Life ◽

Fatigue Damage ◽

Room Temperature ◽

Fatigue Behavior ◽

Fretting Fatigue ◽

Fatigue Load ◽

Bending Fatigue ◽

Fatigue Stress ◽

Contact Loads ◽

Surface Delamination

Bending fretting fatigue behavior of 17CrNiMo6 alloy structural steel at room temperature was investigated under different bending and contact loads; and the [Formula: see text]–[Formula: see text] curve also was built up. The results showed that the [Formula: see text]–[Formula: see text] curve had a “C” shape. The bending fretting fatigue life was mainly dependent on the bending fatigue stress and fretting displacement. The limit of the specimens and the fretting fatigue life were dramatically decreased by fretting actions. The bending fretting fatigue damage changed under varied bending fatigue stress levels. When the wear first occurred, there is a lower bending fatigue stress; and with a higher bending fatigue load, microcracks were generated. However, some serious wear and surface delamination were observed under the highest fatigue load.

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Propagation Behavior of Interfacial Fatigue Cracks in RC Beams Strengthened with Pre-Stressed FRP

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.462-463.177 ◽

2011 ◽

Vol 462-463 ◽

pp. 177-182

Author(s):

Jian He Xie ◽

Pei Yan Huang ◽

Feng Liu ◽

Yong Chang Guo

Keyword(s):

Cyclic Loading ◽

Failure Mode ◽

Fatigue Behavior ◽

Fatigue Cracks ◽

Fatigue Loading ◽

Small Scale ◽

Rc Beams ◽

Interface Cracks ◽

Propagation Behavior ◽

Term Performance

Debonding failure mode usually occurs in the concrete structure flexural strengthened with fiber reinforced polymer (FRP) under cyclic loading. This paper presents an experimental investigation into the fatigue behavior of the FRP-concrete interface of reinforced concrete (RC) beams strengthened with prestressed FRP. 8 small-scale beams were tested under three-point bending cyclic loading. The propagation behavior of the fatigue interface cracks is addressed, and curves showing the growth law of interface cracks are presented. Results from these tests show that the propagation process of interface cracks had three stages, including rapid, stable and unstable growth. The stable propagation phase experienced the most part of the whole test, and the failure mode of all failed beams was debonding following the fatigue fracture of the tensile steel bars. In addition, the influence of FRP prestressing level on the fatigue lives of strengthened beams is discussed, and an empirical formula is developed to predict the fatigue lives of such members. The results show that the fatigue life increases with the prestressed level of FRP. This study provides an insight on the potential long-term performance of FRP-strengthened beams submitted to fatigue loading conditions.

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An investigation into the effect of elevated temperatures on fretting fatigue response under cyclic normal contact loading

Theoretical and Applied Fracture Mechanics ◽

10.1016/j.tafmec.2017.07.018 ◽

2018 ◽

Vol 93 ◽

pp. 144-154 ◽

Cited By ~ 12

Author(s):

F. Abbasi ◽

G.H. Majzoobi

Keyword(s):

Elevated Temperatures ◽

Fretting Fatigue ◽

Normal Contact ◽

Contact Loading

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Developing a new experimental set up to study fretting fatigue behavior under cyclic contact loading

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650117732673 ◽

2017 ◽

Vol 232 (7) ◽

pp. 837-850 ◽

Cited By ~ 1

Author(s):

F Abbasi ◽

GH Majzoobi ◽

MM Barjesteh

Keyword(s):

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Fretting Fatigue ◽

Fatigue Tests ◽

Contact Load ◽

Turbine Engines ◽

Cycle Fatigue ◽

Load Frequency ◽

Contact Loads ◽

Set Up

The disk slot and blade attachment in the gas turbine engines are operated under both cyclic axial and contact loads simultaneously. In this investigation, a new coupon scale testing apparatus is designed and manufactured to study the fretting fatigue behavior of materials under cyclic contact loads. In this cyclic contact load fretting fatigue device (CCLFFD), a simple synchronized electro-mechanical system is used for generating cyclic contact loads with frequency of 0–200 Hz and magnitude of 0–10 kN. The CCLFFD is well instrumented for adjusting, measuring and online monitoring the contact load frequency, contact load graph, and rotation speed of the servomotors. Repeatability and reliability of the test rig were examined by experiment. The performance of the CCLFFD was verified using the experimental results reported in the literature and also by conducting a number of fretting fatigue tests on Al7075-T6 at different contact load frequencies in this work. The results showed that fretting fatigue was significantly affected by the contact load frequency particularly for high cycle fatigue regime. However, the effect was less important for low cycle fatigue regime and totally insignificant for frequencies higher than 80 Hz.

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Forecasting of Tornadoes and Downbursts

The Oxford Handbook of Non-Synoptic Wind Storms ◽

10.1093/oxfordhb/9780190670252.013.3 ◽

2020 ◽

Author(s):

Djordje Romanic

Keyword(s):

Chaos Theory ◽

Prediction Models ◽

Weather Prediction ◽

Small Scale ◽

Weather Forecasts ◽

Wind Speeds ◽

The Past ◽

Extreme Wind ◽

Extreme Wind Speeds ◽

Numerical Weather Prediction Models

Tornadoes and downbursts cause extreme wind speeds that often present a threat to human safety, structures, and the environment. While the accuracy of weather forecasts has increased manifold over the past several decades, the current numerical weather prediction models are still not capable of explicitly resolving tornadoes and small-scale downbursts in their operational applications. This chapter describes some of the physical (e.g., tornadogenesis and downburst formation), mathematical (e.g., chaos theory), and computational (e.g., grid resolution) challenges that meteorologists currently face in tornado and downburst forecasting.

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PyroMEMS as Future Technological Building Blocks for Advanced Microenergetic Systems

Micromachines ◽

10.3390/mi12020118 ◽

2021 ◽

Vol 12 (2) ◽

pp. 118

Author(s):

Jean-Laurent Pouchairet ◽

Carole Rossi

Keyword(s):

Building Block ◽

Building Blocks ◽

Small Scale ◽

Technological Evolution ◽

Research Groups ◽

Function Block ◽

The Past ◽

New Methods ◽

Safety And Reliability ◽

Electronically Controllable

For the past two decades, many research groups have investigated new methods for reducing the size and cost of safe and arm-fire systems, while also improving their safety and reliability, through batch processing. Simultaneously, micro- and nanotechnology advancements regarding nanothermite materials have enabled the production of a key technological building block: pyrotechnical microsystems (pyroMEMS). This building block simply consists of microscale electric initiators with a thin thermite layer as the ignition charge. This microscale to millimeter-scale addressable pyroMEMS enables the integration of intelligence into centimeter-scale pyrotechnical systems. To illustrate this technological evolution, we hereby present the development of a smart infrared (IR) electronically controllable flare consisting of three distinct components: (1) a controllable pyrotechnical ejection block comprising three independently addressable small-scale propellers, all integrated into a one-piece molded and interconnected device, (2) a terminal function block comprising a structured IR pyrotechnical loaf coupled with a microinitiation stage integrating low-energy addressable pyroMEMS, and (3) a connected, autonomous, STANAG 4187 compliant, electronic sensor arming and firing block.

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