Friction and Lubrication in Mechanical Design Episode 1 Part 4 docx

The Contact Between Smooth Surfaces 55

36.

37.

Mossakovski, V. I., “Compression of Elastic Bodies Under Conditions of

Adhesion,” PMM, 1963, Vol. 27, p. 418.

Pao, Y. C., Wu, T. S. and Chiu, Y. P., “Bounds on the Maximum Contact

Stress of an Indented Layer,” Trans. ASME Series E, Journal of Applied

Mechanics, 1971, Vol. 38, p. 608.

Sneddon, I. N., “Boussinesq’s Problem for a Rigid Cone,” Proc. Cambridge

Philosphical Society, 1948, Vol. 44, p. 492.

Vorovich, 1. I., and Ustinov, I. A., “Pressure of a Die on an Elastic Layer of

Finite Thickness,” Applied Mathematics and Mechanics, 1959, Vol. 23, p. 637.

38.

39.

3

Traction Distribution and Microslip in

Frictional Contacts Between Smooth

Elastic Bodies

3.1 INTRODUCTION

Frictional joints attained by bolting, riveting, press fitting, etc., are widely

used for fastening structural elements. This chapter presents design formulae

and methods for predicting the distribution of frictional forces and micro￾slip over continuous or discrete contact areas between elastic bodies sub￾jected to any combination of applied tangential forces and moments. The

potential areas for fretting due to fluctuation of load without gross slip are

discussed.

The analysis of the contact between elastic bodies has long been of

considerable interest in the design of mechanical systems. The evaluation

of the stress distribution in the contact region and the localized microslip,

which exists before the applied tangential force exceeds the frictional resis￾tance, are important Factors in determining the safe operation of many

structural systems.

Hertz [l] established the theory for elastic bodies in contact under

normal loads. In his theory, the contact area, normal stress distribution

and rigid body approach in the direction of the common normal can be

found under the assumption that the dimensions of the contacting bodies

are significantly larger than the contact areas.

Various extensions of Hertz theory can be found in the literature [2-151,

and the previous chapter gives an overview of procedures for evaluating the

area of contact and the pressure distribution between elastic bodies of arbi￾trary smooth surface geometry resulting from the application of loading.

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