Astm stp 1159 1992

STP 1159

Standardization of Fretting

Fatigue Test Methods and

Equipment

M. Helmi Attia and R. B. Waterhouse, editors

ASTM Publication Code Number (PCN)

04-011590-30

As M

1916 Race Street

Philadelphia, PA 19103

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

Library of Congress Cataloging-in-Publication Data

Standardization of fretting fatigue test methods and equipment / M.

Helmi Attia and R. B. Waterhouse, editors.

(STP ; 1159)

Proceedings from a symposium held in San Antonio, Tex., Nov. 12-13, 1990.

"ASTM publication code number (PCN) 04-011590-30."

Includes bibliographical references and index.

ISBN 0-8031-1448-6

1. Materials--Fatigue--Testing--Standards--Congresses. 2. Fatigue

testing machines--Standards--Congresses. I. Attia, M. Helmi

(Mahmoud Helmi) II. Waterhouse, R. B. (Robert Barry), 1922-

III. Title: Fretting fatigue test methods and equipment.

IV. Series: ASTM special technical publication ; 1159.

TA418.38.$68 1992

620.1' 126'0287--dc20 92-17270

CIP

rights reserved. This material may not be reproduced or copied, in whole or in part, in any printed,

mechanical, electronic, film, or other distribution and storage media, without the written consent of the

publisher.

Photocopy Rights

Authorization to photocopy items for internal or personal use, or the internal or personal use of specific

clients, is granted by the AMERICAN SOCIETY FOR TESTING AND MATERIALS for users registered

with the Copyright Clearance Center (CCC) Transactional Reporting Service, provided that the base fee i

of $2.50 per copy, plus $0.50 per page is paid directly to CCC, 27 Congress St., Salem, MA 01970; (508)

744-3350. For those organizations that have been granted a photocopy license by CCC, a separate system of payment has been arranged. The fee code for users of the Transactional Reporting Service is

0-8031-1448-6/92 $2.50 + .50.

Peer Review Policy

Each paper published in this volume was evaluated by three peer reviewers. The authors addressed all

of the reviewers' comments to the satisfaction of both the technical editor(s) and the ASTM Committee

on Publications.

The quality of the papers in this publication reflects not only the obvious efforts of the authors and the

technical editor(s), but also the work of these peer reviewers. The ASTM Committee on Publications

acknowledges with appreciation their dedication and contribution to time and effort on behalf of ASTM.

Printed in Baltimore, MD

July 1992

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

Foreword

In 1988, the ASTM Committee E-9 on Fatigue approved the formation of a Task Group on

Fretting Fatigue Testing to develop standards for the fretting fatigue test methods and equipment. This task group, chaired by one of the editors of this special publication (M. H. Attia)

has recognized the gravity of its responsibility and realized the need for an international cooperative effort to achieve its objective. As a first step towards this goal, the idea of organizing a

symposium on this subject matter was born.

This publication, Standardization of Fretting Fatigue Methods and Equipment, contains

papers presented at the Symposium of the same name in San Antonio, TX on 12-13 November 1990. The symposium was sponsored by ASTM Committee E-9 on Fatigue. Dr. M. Helmi

Attia, of Ontario Hydro Research Division, Toronto, Ontario, Canada and Dr. R. B. Waterhouse, of the University of Nottingham, Nottingham, UK, presided as symposium chairmen

and are the editors of the resulting publication.

The Cover

The photoelastic picture on the cover depicts the change in the stress field and the contact

pressure distribution at the fatigue specimen/fretting pad interface as a result of the change in

the height of the pad. The latter is usually chosen arbitrarily and as such, the variability in the

test results is not unexpected. It is hoped that the picture will capture the attention of those

involved with fretting fatigue testing to the necessity of standardizing the test specimens configuration, methods, and equipment.

The picture was obtained from the Fretting Laboratory, Mechanical Research Department,

Ontario Hydro Research Division.

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

Contents

Overview--M. H. ATTIA AND R. B. WATERHOUSE

A Historical Introduction to Fretting Fatigue--R. B. WATERHOUSE

OPENING PAPER

The Problems of Fretting Fatigue Testing--R. a. WATERHOUSE 13

FUNDAMENTAL ASPECTS OF FRETTING FATIGUE TESTING--CONCEPTUAL FRAMEWORK

Mechanisms of Fretting Fatigue and Their Impact on Test Methods

Development--o. w. HOEPPNER 23

Testing Methods in Fretting Fatigue: A Critical Appraisal--L. VINCENT,

Y. BERTHIER, AND M. GODET 33

Fretting and Contact Fatigue Studied with the Aid of Fretting Maps--

o. B. VINGSBO 49

Variables of Fretting Process: Are There 50 of Them?--J. DOBROMIRSKI 60

FUNDAMENTAL ASPECTS OF FRETTING FATIGUE TESTING--MECHANICS OF CONTACT

The Development of a Fretting Fatigue Experiment with Well-Defined

Characteristics--D. A. HILLS AND D. NOWELL 69

Determination and Control of Contact Pressure Distribution in Fretting Fatigue--

K. SATO 85

Fretting Fatigue Analysis of Strength Improvement Models with Grooving or

Knurling on a Contact Surface--T. HATTORI, M. NAKAMURA,

AND T. ISHIZUKA 101

Effect of Contact Pressure on Fretting Fatigue of High Strength Steel and

Titanium Alloy--K. NAKAZAWA, M. SUMITA, AND N. MARUYAMA ll5

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

FRETTING FATIGUE TESTING--METHODS AND EQUIPMENT

A Critical Review of Fretting Fatigue Investigations at the Royal Aerospace

Establishment--D. B. RAYAPROLU AND R. COOK

Fretting Fatigue in the Power Generation Industry: Experiments, Analysis, and

Integrity Assessment--T. C. LINDLEY AND K. J. NIX

Techniques for the Characterization of Fretting Fatigue Damage--c. RUIZ,

Z. P. WANG, AND P. H. WEBB

The Influence of Fretting Corrosion on Fatigue Strength of Nodular Cast Iron and

Steel under Constant Amplitude and Load Spectrum Tests--G. FISCHER,

V. GRUBISIC, AND O. BUXBAUM

Adaptation of a Servohydraulic Testing Machine to Investigate the Life of

Machine Components Operating under Fretting Conditions--J. LABEDZ

129

153

170

178

190

ENVIRONMENTAL AND SURFACE CONDITIONS

Improving Fretting Fatigue Strength at Elevated Temperatures by Shot Peening in

Steam Turbine Steel--Y. MUTOH, T. SATOH, AND E. TSUNODA

The Fretting Fatigue Properties of a Blade Steel in Air and Vapor Environments--

D. YUNSHU, Z. BAOYU, AND L. WEILI

The Application of Electrochemical Techniques to Evaluate the Role of Corrosion

in Fretting Fatigue of a High Strength Low Alloy Steel--s. PRICE AND

D. E. TAYLOR

199

210

217

NONCONVENTIONAL MATERIALS AND TEST METHODS

ACSR Electrical Conductor Fretting Fatigue at Spacer Clamps--A. CARDON,

L. CLOUTIER, M. ST-LOUIS, AND A. LEBLOND

Fretting Fatigue of Carbon Fiber-Reinforced Epoxy Laminates--o. JACOBS,

K. SCHULTE~ AND K. FRIEDRICH

231

243

CLOSING PAPER

Fretting Fatigue Testing: Current Practice and Future Prospects for

Standardization--M. H. ATTIA

Author Index

Subject Index

263

277

279

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

STP1159-EB/Jul. 1992

Overview

Introduction

With the present state of knowledge, the fretting fatigue problem is commonly approached

empirically by testing the material/component under simulated conditions of contact and

environments. The extreme difficulty in performing fretting fatigue testing manifests itself not

only through the large number of process variables but also through their mutual interactions

and the self-induced changes in the tribological system. The discrepancy among published

data is, therefore, not surprising. The possibility and potential for improving the repeatability

of test data do, however, exist with proper and comprehensive understanding of the sources of

uncertainties.

Objectives

The main objectives of this symposium/publication are as follows:

1. Review the present state of knowledge and the current fretting fatigue testing practice.

2. Identify the areas of uncertainties in conducting fretting fatigue testing, including the

design of the test specimens, as well as the measurement and control aspects.

3. Identify the measures that should be taken to improve the repeatability of test results and

to minimize their dependence on the design of the test equipment.

4. Examine the future prospects for standardization, and identify the areas that warrant

further research.

This book will be useful to tribologists, physicists, and mechanical engineers who are

involved with fretting fatigue testing and those who are concerned with contact problems, particularly where fatigue and vibration are concerned, for example, in turbines, generators, aircraft, structures involving steel ropes, and so on. The paper presented by Hattori et al., for

example, shows how problems have been overcome in the design of steam turbines. Vincent

et al. and Vingsbo discussed the use of fretting maps for controlling the fretting fatigue damage

in practice. Other papers show the effectiveness of certain preventative measures such as surface treatment and cathodic protection in marine environments. The papers presented in this

publication cover the response of common-place materials, such as steel and aluminum, as

well as the less conventional materials such as composites.

Overview of the Papers of the Symposium

This special technical publication contains 20 papers written by renowned authorities in this

field. The opening keynote paper, presented by R. B. Waterhouse, provides a global overview

of the problems of fretting fatigue testing and presents the author's perspective and views on

the main issues that should be addressed in any attempt to standardize fretting fatigue testing.

In addition, a total of four invited keynote papers were also presented by Vingsbo, Hoeppner,

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

2 FRETTING FATIGUE TEST METHODS AND EQUIPMENT

Hills, and Vincent to simulate and set the stage for focused and fruitful discussion during the

symposium. The closing paper by Attia, the Chairman of the ASTM Task Group E9.08.02 on

Fretting Fatigue Testing, examines the future prospects for standardization in relation to the

current practice. The paper presents also the results of a survey in which the input was solicited

from 65 active researchers in various parts of the world.

This special technical publication reflects the trends and testing philosophy in ten different

countries and is, therefore, characterized by its international flavor. Apart from the opening

and closing position papers, the papers of this symposium are grouped in five sections:

FundamentaI Aspects of Fretting Fatigue Testing--Conceptual Framework

This section includes four papers that provide a conceptual framework for the mechanical

and physical interactions associated with the fretting fatigue process and testing. Following a

brief presentation of the historical evolution of the fretting fatigue testing, Hoeppner reviewed

the mechanism of fretting fatigue and the contributions that have been made in understanding

the crack nucleation and in characterizing the fretting fatigue damage. He underlined those

parameters that can be considered as mechanism controlling and presented the recent developments in micromechanical modeling. The paper concluded with the recommendation for

standards development and the identification of some areas that warrant further research.

Vincent, Berthier, and Godet applied their concept of "velocity accommodation" to the

fretting process and showed that the relative displacement and velocity difference between the

core of contacting solids are accommodated at different sites (the rubbing solids, their interface, or the surface screens) and according to different modes (elastic, rupture, shear, and rolling). Depending on the surface tensile stresses and whether adhesive welds break before crack

initiation, it was indicated that the material responds to fretting in three different ways: no

degradation, crack formation, and particle detachment. Since different material responses can

be observed during a single test, the authors stressed the importance of constructing "fretting

maps" to identify the material response to specific running conditions. To extend the velocity

accommodation and fretting maps concepts to fretting fatigue testing and to overcome the

classical problem of the dependence of the displacement amplitude on the body stress level,

the authors proposed a new "fretting-static fatigue" testing method. This method, which is

based on applying a constant body stress and controlling the slip amplitude independently,

requires a set of fretting maps to be produced for different loads, slip amplitudes, and number

of cycles. The authors proposed also a measure for the "severity" of the test, and outlined how

the design engineer can use these maps to identify and avoid fretting fatigue failures. In this

paper, some fundamental questions were raised, regarding the contact mechanics parameters

that govern crack initiation/propagation, and the significance of the drop in the fatigue

strength measured in fretting fatigue test machines. The latter issue was discussed in relation

to the formation/retainment of wear debris, and the effect of the machine stiffness.

The subject of fretting maps, which define the effect of the process parameters on the extent

of the stick, partial- and gross-slip regimes, was also discussed by Vingsbo. Using a simple

model of surface asperities in elastic contact with a' perfectly flat semi-infinite body under

cyclic loading, the author concluded that surface fatigue is promoted by fretting under mixed

stick-slip conditions, both in terms of cyclic stress concentrations and plastic deformation in

the contact zone. The author's view on establishing fretting maps for a given tribo-system to

control the fretting fatigue damage in practice is readily applicable to the design of a controlled

fretting fatigue testing system.

Perhaps the most difficult problem to be encountered in developing standards for a controlled and well-defined fretting fatigue test is handling the large number of process variables.

The popular list of variables, which was originally assembled by Collins in 1964, includes as

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

OVERVIEW 3

many as 50 variables! In reviewing the stress models, which were successfully used to predict

the fretting fatigue strength, Dobromirski argued that the vast majority of these variables,

which are not explicitly included in the stress models, can be treated as "secondary" variables

that influence the process through their effect on the "primary" variables. The latter is a short

list of three variables, namely, the coefficient of friction, the displacement amplitude, and the

contact pressure. The coefficient of friction was further singled out and identified as the main

primary variable. By re-examining a large sample of available fretting wear/fatigue data, from

this perspective, the author was able to use the coefficient of friction as a common denominator to explain the effect of various process parameters on the fretting fatigue test results.

Beyond the obvious benefit of reducing the list of variables to a manageable and practical number, Dobromirski's analysis should be taken one step further to alert all of us that the time has

come to treat the coefficient of friction as one of the parameters that should be measured in

fretting fatigue testing. It will be noted throughout this book that the emphasis on the critical

role of friction force is echoed by many others.

Fundamental Aspects of Fretting Fatigue Testing--Mechanics of Contact

This section includes four papers that deal with the theoretical aspects of the mechanics of

contact, and the application of numerical techniques; for example, finite-element and boundary-element methods to calculate the contact stresses. Experimental verification, using the

caustics method, is also presented. The authors maintained their focus on the main objectives

of this symposium and presented their analysis in terms of two important issues: the design of

the fretting pad/fatigue specimen and the method of applying the normal contact load.

The paper presented by Hills and Nowell is centered around the idea that specimen/pad

geometry should be amenable to a well-defined stress field and fracture mechanics analysis.

They highlighted the drawbacks associated with the flat-ended fretting pad; for example, the

singularities in the contact stress distributions and the difficulty in defining the slip-stick zones.

They recommended the adoption of a "cylindrical bridges against flat tensile specimens" configuration, since it allows changing the contact size while keeping constant normal load, as well

as controlling the normal and tangential contact forces independently. The paper deals with

some points of interest to those involved with the task of developing standards for fretting

fatigue tests, namely, the contact size threshold phenomenon and the nature of the distribution

of the coefficient of friction over the contact area.

Using the boundary element method, Sato studied the effects of clamping position (central

versus edge clamping) as well as the bridge height on the magnitude and the distribution of the

contact pressure at the specimen/bridge interface. The results of the plane-stress analysis of the

bending fatigue problem were validated experimentally, using the method of caustics. The

concept of"equivalent stress amplitude," as defined by Tresca's yield criterion, was proposed

by the author for estimating the fretting fatigue strength. From the S-N fretting fatigue test

results, it was established that the bridge height affects the fatigue life only under central clamping conditions (negative effect). The author was successful in interpreting these results in relation to the contact pressure amplitude, defined as half the difference between the compressive

and tensile contact pressures at the outer edge of the contact area. The paper was concluded

with the recommendation to use either central clamping when the bridge height-to-contact

length H/L ratio is unity, or to use edge clamping for fretting fatigue tests with other H/L ratios.

To improve the fretting fatigue strength, the author demonstrated a way of reducing the contact pressure amplitude through the machining of grooves in the fatigue specimen near the

end of the bridge.

The application of the boundary element method for calculating the contact pressure distribution and the concept of controlling it through grooving and surface knurling were also

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

4 FRETTING FATIGUE TEST METHODS AND EQUIPMENT

discussed by Hattori, Nakamura, and Ishizuka. In this paper, the fretting fatigue limit was predicted using the fracture mechanics approach. These predictions were also verified experimentally. The paper addresses some interesting points in relation to the measurement and

modeling of the effective stiffness of the contact interface. The example given in the paper for

improving the fretting fatigue strength through optimization of the groove geometry (to cour~-

teract the negative notch effect with the positive effect associated with the rise in the threshold

stress intensity range factor) provides a methodology for designing the configuration of fretting

fatigue test specimens.

The effect of the average contact pressure on the fretting fatigue strength was further invesL

tigated experimentally by Nakazawa, Sumita, and Maruyama. The test results indicated that

the relationship between the fretting fatigue life and the contact pressure is influenced by the

stress amplitude. At low-stress amplitude (<20% of the 0.2% PS of high strength steel), this

relationship is nonmonotonic and passes through a minimum and then a maximum before

reaching a constant level. At high-stress amplitude (>40% of the 0.2% PS), the increase in the

contact pressure leads to a continuous drop in the fretting fatigue life. The authors reported

also the increase in the frictional stress amplitude with the increase in the contact pressure. For

the steel used, it has been indicated that the crack initiation sites shift from the middle portion

of the contact area to the outer edge as the contact pressure is increased. This observation is of

a particular importance to fracture mechanics analysts who usually assume that cracks initiate

at the contact edge.

Fretting Fatigue Testing--Methods and Equipment

In this section which includes five papers, the present state of the art in fretting fatigue testing

is reviewed, and the relative merits of various test methods are evaluated. A few recommendations were made regarding the adoption of commercial equipment, proven techniques and

experimental test rigs, as a starting point for standards development. Some interesting concepts and observations were also made, providing guidelines for conducting proper simulative

tests.

The fretting fatigue testing and research activity at the Royal Aerospace Establishment

(RAE) the U.K. was critically reviewed by Rayaprolu and Cook. Over the last 15 years, the

test methods and test variables at RAE were progressively changing to satisfy specific requirements and objectives. Four stages or test series were identified by the authors to reflect such a

change. The conventional fretting fatigue setup with a proving ring was used in the first test

series to investigate the effects of the pad span, contact load and body loading type on the

fatigue endurance. The second test series was motivated by the need for knowing the local

stresses induced by fretting in order to apply fracture mechanics models. Here, the frictional

force measurement was introduced. In the third stage, the experimental research effort was

directed towards identifying the separate effects of the contact, frictional, and body loads on

the fatigue process. Using a biaxial fatigue machine with phase linked actuators, a fourth series

of tests is being currently undertaken to examine the effect of cyclic load variations on the

cyclic frictional load, as well as crack initiation and propagation. The paper summarizes also

the work related to fracture mechanics modeling at RAE. Recommendations for standard test

setup, procedures, and future work were presented in the last two sections of the paper. To

improve the fracture mechanics prediction capability, the effect of the contact parameters on

crack initiation and growth, particularly with reference to initiation sites and angular and short

crack growth, was identified as an important area for further research. It is worth noting that

this recommendation is well founded by the observations made by Nakazawa et al.

The paper given by Lindley and Nix described the two fretting fatigue test methods used at

the National Power Technology and Environmental Centre in the United Kingdom. These

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

OVERVIEW 5

methods are similar to those used and recommended in the previous paper by Rayaprolu and

Cook, namely, the proving ring and the biaxial test rigs. The advantages of the latter system

were discussed in terms of controlling the contact load and the relative slip between the specimen and the pad, as well as applying variable amplitude loading. The paper describes also

alternative fretting pad geometries and emphasizes the requirements for frictional force measurement during the test. The two approaches of fretting fatigue analysis, the S-N curve and

the fracture mechanics modeling, were also reviewed.

For a proper simulative fretting fatigue testing, Ruiz, Wang, and Webb introduced the

fatigue-fretting damage parameter (FFDP), as a measure of the severity of fretting fatigue damage. This parameter is a function of the tangential stress along the line of contact, the interface

shear stress, and the relative slip and, therefore, includes the variables that control the initiation of fretting surface damage (wear) and the growth of the cracks. The main thrust of the

paper is centered around the importance of getting the three components of the FFDP right

in any test designed to reproduce the conditions prevailing in a real structural joint. The paper

discussed further the issue of controlling these variables in three types of tests: biaxial, tension/

compression, and 3-point bending tests. The authors pointed out the proper choice of the test

method, depending on the ductility of the material tested.

The paper presented by Fischer, Grubisic, and Buxbaum deals with a very important and

fundamental issue in fretting fatigue testing: the effect of load sequence. The experimental

study carried out by the authors on the fretting fatigue behavior of nodular cast iron under

constant amplitude and load spectrum (random sequence) throws the light on a few important

findings. First, the common test practice of constant stress amplitude produces more reduction

in the fretting fatigue strength because of higher slip amplitude and higher degree of "embedding." Second, the widely accepted notion of the negative effect of the contact pressure on the

fretting fatigue strength (under constant stress amplitude) cannot be extended to the case in

which the stress amplitude follows a random sequence. Third, the significant improvement in

the fretting fatigue strength with residual compressive stresses, for example, due to shot peening, was not observed in plain fatigue testing under spectrum load. Although these conclusions

cannot be generalized, at the moment, beyond the test conditions reported by the authors, they

demonstrate the importance of proper simulation of the loading conditions encountered in

practice and suggest the improved repeatability of the test results under random sequence

loading, even when the contact pressure and residual stresses are not precisely controlled and

defined.

Labedz's paper deals with the adaptation of commercially available servo-hydraulic testing

machines and the use ofa univeral test rig for fretting testing. The proposed test method is in

harmony with Dobromirski's concept of primary/secondary variables and considers only five

essential test variables. The author brings to our attention two test parameters that are usually

ignored in fretting wear/fatigue testing: the contact temperature and the residual stresses. The

effect of the latter was experimentally investigated to confirm its importance and to demonstrate the proposed test method.

Environmental and Surface Conditions

This section includes three papers that deal with the effect of surface residual stresses and

the environmental conditions (for example, temperature, vapor content, and corrosivity) on

the fretting fatigue test results. These papers point out the importance of monitoring and duplicating the environmental conditions and the state of stresses at the surface of the specimen.

Some experimental techniques, for example, X-ray diffraction, scanning electron microscopy

(SEM), atomic emission spectroscopy (AES), Mossbauer spectrometry, and electrochemical

techniques were described.

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

6 FRETTING FATIGUE TEST METHODS AND EQUIPMENT

The effects of the compressive residual stresses and the environmental temperature on the

fretting fatigue test results were investigated by Mutoh, Satoh, and Tsumoda. Some considerations for testing and measuring frictional forces at elevated temperatures were discussed.

The paper examines also the relationship between the coefficient of friction and the stress

amplitude. It has been concluded that for the given test conditions, this relationship is unique

regardless of the temperature and the surface residual stresses. This behavior was attributed to

the insensitivity of the following mechanisms to surface and environmental conditions: oxidation (to temperature), and surface roughness and hardness (to shot peening).

The paper presented by Yunshu, Baoyu, and Weili focused on the effect of the environment

on the debris structure and its tribological properties. Using surface analysis techniques, the

authors concluded that if the environmental conditions promote the wear debris to act as an

effective solid lubricant, the fretting fatigue strength will be partially restored, as in the case of

blade steel fretted in vapor. They also concluded that the environmental effects become less

important in the presence of compressive stresses.

The paper presented by Price and Taylor is concerned with two issues: the synergistic effect

of the mechanical and electrochemical components of the fretting fatigue process and the

application of electrochemical techniques to separate and evaluate the role of corrosion in tests

run in aqueous environment. An experimental setup was developed to control the corrosivity

of the medium and to identify the electrochemical dissolution process through the use of

impressed cathodic protection. For the test conditions specified in the paper, the authors

concluded that the electrochemical processes have the greatest influence on the fatigue life of

high-strength low-alloy steel. The paper draws the attention to the requirement of assessing the

contribution of the corrosion action in fretting fatigue testing, and provides a method for

achieving that.

Nonconventional Materials and Test Methods

This section includes two papers that deal with nonconventional test configuration and

materials. The fretting fatigue testing system developed by Cardou, Cloutier, St. Louis, and

Leblond to test overhead electrical conductors is based on exciting the conductor at the span

midpoint, with a controlled cyclic deflexion. The concept of primary and secondary test variables was independently applied in this paper, and two test methods were followed, namely

the wire fracture time sequence and fracture location analysis.

In the paper presented by Jacobs, Friedrich, and Schulte, a special test setup was developed

to study the mechanism of fretting fatigue of carbon fiber reinforced expoxy (CFRE) laminates. In contrast to the observation made by Lindley and Nix, the authors found that the

fretting fatigue life of CFRE is significantly affected by the fretting pad material. This was contributed to the mechanism of interaction between fretting wear damage and fatigue, which is

also sensitive to the contact pressure and the hardness of the fretting pad material. The authors

established that the fretting fatigue mechanism of fiber reinforced polymers is characterized

by multiple matrix cracking along the fibers and, therefore, the available fracture mechanics

models are not applicable to these materials. A theoretical model for the "fretting fatigue load

versus number of cycles to failure" and the "specific pseudo-wear rate" was developed and

verified experimentally.

Acknowledgment

The editors are indeed grateful to the authors for their valuable and original contributions.

The effort of the reviewers in streamlining and improving the clarity of the presentation is

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

OVERVIEW 7

ton, TX, for his support and his instrumental role in forming the ASTM Fretting Fatigue Testing task group. A word of appreciation is also due to Messers. G. Clarke, D. B. Craig, and N.

S. D'Silva, of the Mechanical Engineering Department, Ontario Hydro Research Division, for

their support. The support of the Department of Materials Engineering and Materials Design,

University of Nottingham is indeed appreciated.

The editors would like to express their thanks to the officers and members of the ASTM

Committee E-9 on Fatigue for their support and also to the publication staffofASTM for their

patience and support that made this publication possible.

This publication is only one aspect of the symposium. The sessions and the discussions contribute greatly to the mission of the symposium. The effort of the co-chairmen of the sessions

is acknowledged and appreciated. The editors are thankful to the attendees of the symposium

for the interesting points and useful comments they made during the discussions that followed

the paper presentaion, and during the panel discussion session. Their enthusiasm to follow up

this symposium with similar conferences in the future is appreciated and well taken. The editors hope that those concerned with the subject of fretting fatigue will find this publication

useful and stimulating.

M. Helmi Attia

Ontario Hydro Research Division, Toronto,

Ontario, Canada; symposium chairman and

editor.

R. B. Waterhouse

Department of Materials, Engineering and

Materials Design, University of Nottinghamsymposium chairman and editor.

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

R. B. Waterhouse ~

A Historical Introduction to Fretting Fatigue

REFERENCE: Waterhouse, R. B., "A Historical Introduction to Fretting Fatigue," Standardization of Fretting Fatigue Test Methods and Equipment, ASTM STP ]15 9, M. Helmi Attia and

R. B. Waterhouse, Eds., American Society for Testing and Materials, Philadelphia, 1992, pp. 8-

KEY WORDS: fretting fatigue, fatigue properties, historical perspective, crack propagation

Fretting was first reported by Eden et al. in 1911 [1 ] who found that brown oxide debris was

formed in the steel grips of their fatigue machine in contact with a steel specimen. It was not

until 1927 that Tomlinson [2] conducted the first investigation of the process and designed

two machines to produce small-amplitude rotational movement between two annuli in the

first case, and an annulus and a flat in the second. The movement was controlled by a long

lever system. Since the resultant debris on his steel specimens was the red iron oxide c~Fe20~,

which had arisen from chemical reaction with oxygen in the air, he coined the phrase "fretting

corrosion." He also established that the damage could be caused by movements with amplitudes as small as a few millionths of an inch (~ 125 nm) and the important fact that relative

movement had to occur, which he termed "slip."

The effect that fretting could have on fatigue properties was first investigated by WarlowDavies [3] in 1941, who produced fretting damage on the gage length of steel fatigue specimens

and found a subsequent reduction in fatigue strength caused by the pitting of the surface, of

between 13 and 17%. This was to be expected, but later investigations, particularly by McDowell [4] showed that the conjoint action of fretting and fatigue, which is the usual case in practice, was much more dangerous, producing strength reduction factors of 2 to 5 and even

greater. Fenner and Field [5] in 1958 demonstrated that fretting greatly accelerated the crack

initiation process. I published my first research paper in 1961 and showed that recrystallization

of the ferrite occurred in the fretted region when a bright drawn mild steel was subjected to

fretting fatigue [6]. The first major investigation was by Nishioka and Hirakawa who published a series of six detailed papers that were inspired by a problem encountered in the rolling

stock of the Shinkansen [ 7]. Subsequent experimental investigations have been based on their

valuable work. They also were the first people, together with Liu et al. [8], to attempt an analysis of fretting fatigue. This is an area that has seen great developments in the succeeding years

and forms a major part of this publication.

References

[ 1] Eden, E. M., Rose, W. N., and Cunningham, F. L., "Endurance of Metals," Proceedings of the Institute (f Mechanical Engineers" Vol. 4, 1911, pp. 839-974.

[2] Tomlinson, G. A., "The Rusting of Steel Surfaces in Contact," Proceedings q/the Royal Society, A

Vol. 115, 1927, pp. 472-483.

Department of Materials Engineering and Materials Design, University of Nottingham, University

Park, Nottingham NG7 2RD, England.

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

WATERHOUSE ON A HISTORICAL INTRODUCTION 9

[3] Warlow-Davies, F. J., "Fretting Corrosion and Fatigue Strength," Proceedings of the Institute on

Mechanical Engineers, Vol. 146, 1941, p. 32.

[4] McDowell, J. R., "Fretting Corrosion Tendencies of Several Combinations of Materials," Symposium on Fretting Corrosion, STP 144. American Society for Testing and Materials, Philadelphia,

1953, pp. 24-39.

[5] Fenner, A. J. and Field, J. E., "La Fatigue Dans les Conditions de Frottement," Rev. MOt., Vol. 55,

1958, pp. 475-485.

[6] Waterhouse, R. B., "Influence of Local Temperature Increases on the Fretting Corrosion of Mild

Steel," Journal of Iron and Steel Institute. Vol. 197, 1961, pp. 301-305.

[7] Nishioka, K. and Hirakawa, K., "Fundamental Investigations of Fretting Fatigue," Bulletin of the

Japan Society of Mechanical Engineers, Vol. 12, 1969, pp. 180-187,397-407, 408-414, 692-697;

Vol. 15, 1972, pp. 135-142.

[8] Liu, H. W., Corten, H. T., and Sinclair, G. M., "Fretting Fatigue Strength of Titanium Alloy RC

130B," Proceedings ofASTM, Vol. 57, 1957, pp. 623-641.

Downloaded/printed by

University of Washington (University of Washington) pursuant to License Agreement. No further reproductions authorized.

Thư viện tri thức trực tuyến

Nội dung xem thử

Mô tả chi tiết

Tài liệu tương tự (6)

Astm stp 837 1984

Astm stp 15c 1962

Astm stp 531 1973

Astm stp 642 1978

Astm stp 849 1984

Astm stp 1601 2017