Potential SiO_2/CRF bilayer perturbation aerogel target for ICF hydrodynamic instability experiment

摘要

The SiO_2/carbonized resorcinol formaldehyde (CRF) bilayer perturbation aerogel target was designed and fabricated to investigate the growth of Rayleigh-Taylor instability (RTI) at "SG-H" laser facility. The target was composed of SiO_2 and CRF aerogel sheet, whose density and microstructure were controllable. To begin with, freestanding CRF aerogel sheet was prepared by sol-gel and carbonization process. Then, as the seed of the growth of RTI, sine-like perturbation patterns were introduced onto the surface of CRF aerogel sheet by picosecond laser micro-machining process. Finally, SiO_2 aerogel sheet was directly formed on the patterned surface of CRF aerogel sheet by sol-gel process not only to avoid the use of adhesive but also to eliminate the gaps between the two aerogel sheets. The parameters of the target, such as perturbation period (T), perturbation amplitude (A), the thickness of CRF aerogel sheet (H_1) and the thickness of SiO_2 aerogel sheet (H_2), were measured. The pore size distribution, density homogeneity and laser machining process were discussed. The interface between CRF aerogel sheet and SiO_2 aerogel sheet was characterized.