Investigation On The Nonlinear Deformation Of Composite Interface Using Finite Element Simulation

In mathematical computation,the finite element method(FEM)is a numerical technique to solve the approximate solution of the boundary value problem in the partial differential equation.FEM is a process of simplifying complex problems,i.e.,the problems with complicated,irregular,or unsolvable are firstly divided into a large number of finite elements,then combining them into the final equation for the next quantitative solution.The FEM provides a way to deal with complex problems and further to perform larger-scale calculations with the help of computers.The interface plays an important role in Metal matrix composites(MMCs).In the loading process of MMCs,the highly nonlinear problems of the strain and stress,strain and displacement,and the interface of two phases will bring difficulties to the mechanical stimulation of the interface.Meanwhile,it is difficult to study the deformation properties of interface or interfacial micro-region in MMCs by traditional experimental methods because of the microscopic and complicated properties of the interface,and the coupling effect among the interfaces.Inspired by the micro/nano-mechanical research of uniaxial compression experiment on the composite micro/nano-pillars with a single slanted interface,in this paper,ABAQUS software with excellent nonlinear processing ability will be employed to model similar composite micro/nano-pillars and then to simulate the mechanical properties of the interface under uniaxial compression.The Si C/Al MMCs with the great application were selected as model materials.The research results have been listed as follows.(1)For the pure Al and Si C pillars,under the same deformation strain,the stress distribution was uniformly,and the stress concentration focused on the areas near to the bottom with constraint conditions.The main deformation properties were dominated by Al-parts for the stress of Si C is much larger than that of Al.(2)For Si C/Al composite pillar with a single 0° interface,under the same deformation strain,the obvious inhomogeneous deformation appeared in the local area of Al-parts,and an obvious strain gradient appeared from the top to the interface of the pillar.Which corresponded to the phenomena of upsetting and aberration on the top of the metal pillars under uniaxial compression.(3)For Si C/Al composite pillars with a single slanted 45°interface,the interfacial shear appeared upon a certain pressure.There were a series of zonal distributions of uneven stress parallelling to the interface from the top to the interface along the direction of the vertical interface.It was concluded that the deformation stress appeared gradient distribution and possessed a corresponding parallel relationship with the interface.In this study,the Si C/Al composite pillars with a single slanted interface were modeled by ABAQUS,and the mechanical properties were studied under the gradient and nonlinear deformation,which offered a theoretical reference for further exploring the nonlinear problem of gradient deformation in heterogeneous interfaces.