Investigation Of The Coupled Elasto-magnetic Behavior Of Particle-reinforced Composites With Interface Effect

Particle reinforced composites are widely used in modern industrial due to their high specific stiffness and strength.When the phase components of particle reinforced composites are magneto-elastic materials with piezomagnetic effect,we need to study not only the elastic properties of the composites,but also the piezomagnetic properties of the composites.Because of the unique coupling effect based on elasto-magnetic interaction,piezomagnetic materials have attracted extensive and lasting attention in the field of intelligent manufacturing and active structures.Specific applications include:force magnetic converter,magnetic sensor,strain gauge,ultrasonic generator,stress sensor and so on.These applications in industry need new materials which are sensitive to elastic changes.It happens that most piezomagnetic materials have excellent piezomagnetic properties.Before exploring the effective magnetoelastic properties of piezomagnetic particle reinforced composites,we need to study the elastic field and piezomagnetic field distribution of the inhomogeneities of piezomagnetic particle reinforced composites from the perspective of continuum mechanics.In recent years,the development of nano scale particle reinforced composites is rapid.Due to its typical nano scale characteristics,nano materials can show many novel physical effects,which are different from macroscopic materials.The unique physical properties of nanostructures are enough to change the macroscopic properties of materials,which makes the research of particle reinforced composites from the traditional micro scale into the nano scale.Due to the large area v.s.volume ratio of nano inhomogeneities,the size effect and interface effect of inhomogeneities can not be ignored.In order to accurately and efficiently predict the magnetoelastic field distribution of materials,we need to use different coupling theories to describe the magnetoelastic constitutive relationship of materials.For the above problems,this paper first studies the elastic field distribution of nano inhomogeneities considering the interface / interphase effect.Based on the analytical solutions of the elastic field of interface model and interphase model,we select the Ga As-Al N heterostructure to explore the influence of the interface and interphase elasticity and the size of the inhomogeneities on the elastic field distribution of nano inhomogeneities,meanwhile,the differences and internal relations between the interface model and the interphase model are further explored.On the premise of knowing the elastic field distribution of the heterostructure,the analytical expression of the piezomagnetic field distribution of the nanostructure considering the interface effect is obtained by using the semicoupled model.The influence of interface elasticity,size effect and inhomogeneous elasticity on the distribution of piezomagnetic field is discussed.However,the semicoupled model is only suitable for weakly coupled materials.In order to overcome the limitations of the semicoupled model and improve the prediction accuracy of the coupled model,based on the elastic Green’s function and Fourier transform,the integral expression of the magnetoelastic unified Green’s function is derived,and the correctness of the magnetoelastic Green’s function and its derivatives is verified.The magnetoelastic field distributions of transversely isotropic and isotropic piezomagnetic nano inhomogeneities are obtained by assuming different piezomagnetic materials.Finally,based on the magnetoelastic field distribution of piezomagnetic inhomogeneities,the effective properties of piezomagnetic particle composites under the approximation of dilute method and Mori-Tanaka method are explored,and the influence of permeability isotropic simplification on the accuracy of effective properties prediction under the two approximation methods is discussed.