Study on clamping deformation of the low-stiffness cylindrical mirror considering adhesive effect

Abstract As a cylindrical shell optical component, silicon X-ray mirrors exhibit large diameter-to-thickness ratios and low stiffness. Hot melt adhesive clamping is recognized as the safest and most convenient clamping method for hard and brittle mirrors. However, the adhesive clamping of low-stiffness mirrors is subject to multiple influences of the bonding method and stress, which leads to the deformation of the mirrors. In this paper, we analyze the process of hot melt adhesive clamping of mirrors and reveal that the uneven distribution of adhesive strength between the mirror and the fixture is the root cause of the mirror’s deformation. For this reason, we established a finite element simulation model of the whole process of the mirror’s adhesive clamping and considered the effect of nonlinear variation of adhesive strength with the colloidal temperature to achieve an accurate prediction of the mirror’s adhesive clamping deformation. Comparison experiments between whole surface bonding and runner bonding of mirrors show that reducing the bonding area can significantly reduce the deformation of mirrors caused by uneven adhesive strength. The experiments show that the constructed simulation model can accurately predict the deformation of mirrors caused by adhesive clamping, which can guide the selection of the mirror’s adhesive clamping parameters.