Simulation method for precision bonding structure with micron scale adhesive layer

In the manufacturing process of precision instruments, many parts are connected by adhesive. Because of the high manufacturing accuracy of precision instrument, the design value of the bonding gap is generally in the scale of microns. This thin gap in the instrument may lead to nonlinear displacement and deformation of instrument under the condition of multi physical field when the precision instrument is working, thus affecting the accuracy and stability of instrument. In this paper, a simulation method for bonding structure with micron scale adhesive layer is established. Through a case of simplified model and a case of mesh method of a precision instrument adhesive structure, the finite element analysis is carried out. The basic principle of geometric model simplification and mesh method in the simulation is obtained. In order to ensure the accuracy of the three-dimensional stress analysis, the adhesive layer with a local thickness which is less than 1/10 of the average thickness is simplified as a hole. The length- width ratio of the meshes should be controlled about 1:10. For stress analysis, second order hexahedron element should be used and the element angle should between 10 degrees to 170 degrees. Under these conditions, the simulation of the bonding structure with micron scale adhesive layer can be carried out with high accuracy and high efficiency.