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Abstract Magneto-electro-elastic composite materials (MEEMs), comprised of piezomagnetic and piezoelectric phases, possess superior mechanical performance and intrinsic electro-magnetic-mechanical coupling effects. MEEMs have been widely used in various hi-tech smart structures and devices, such as, micro power generators, transducers and actuators. In practical engineering applications, due to the intrinsic brittleness of MEEMs, the smart devices and structures made of MEEMs will easily suffer from surface contact damage when subjected to the highly concentrated local contact loads and friction forces. In addition, these structures are often served in the vibration environment. Therefore, fretting contact damage and fatigue failure inevitably occur in these smart devices. In this paper, the two-dimensional fretting contact between an MEEM half-plane and a rigid conducting cylindrical punch are investigated to improve the resistance to fretting contact damage and electromagnetic failures. The punch is assumed to be a perfect electro-magnetic conductor with constant electric potential and constant magnetic potential within the contact region. Since the fretting contact problem is loading history dependent, the two bodies are brought into contact first by a monotonically increasing normal load, and then by a cyclic tangential load, which is less than that necessary to cause complete sliding. It is assumed that the whole contact region contains an inner stick region and two outer slip regions where Coulomb’s friction law is applied. By using the Fourier integral transform technique, the problem is reduced to a set of coupled Cauchy singular integral equations. An iterative method is used to determine the unknown stick/slip region, normal contact pressure, electric charge, magnetic induction and tangential traction. The effects of the friction coefficient, total electric charge, total magnetic induction and conductivity of the punch on the surface electromechanical fields are discussed for different loading phases. It is found that the peak value of tangential traction for the insulating punch is larger than that of the conducting punch, but the size of the stick region is smaller than that of the conducting punch. The maximum values of the in-plane tensile stress, the in-plane electric displacement and the in-plane magnetic induction occur at the edges of the contact region during the tangential loading phase, which implies a possible site of the contact damage and fretting crack initiation.
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Received: 21 November 2019
Published: 28 April 2020
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2020, Vol. 41 
