Simulation And Experimental Study Of Carbon Black Based Composite Materials With High Photoacoustic Conversion Efficiency

Laser ultrasound is a new ultrasound generation technic that uses photoacoustic effect（PA）to generate high-frequency and broadband ultrasound.In recent years,laser ultrasound has shown great potential in industrial flaw detection and medical treatment due to its superior performance.Among the photoacoustic conversion materials currently used for laser ultrasound,metal-based materials and carbon-based materials are two materials with great potential,and their photoacoustic conversion efficiency can be further optimized and improved.However,the research on simulation models of composite materials is very scarce at present.A three-dimensional structure model was established by using carbon black（CB）-polydimethylsiloxane（PDMS）composite materials in carbon-based photoacoustic conversion composite materials.The influence of carbon black particle size,light absorption coefficient and other properties on the photoacoustic conversion effect of composite materials was studied and verified by experiments.In the light of the structure of composite materials,a three-dimensional model of the material was built by a finite element analysis software.Based on the model,the effects of carbon black particle size,light absorption coefficient,and thermal diffusion coefficient on the photoacoustic conversion efficiency of CB-PDMS was simulated.In the experiment,carbon black with different properties was selected,and a composite film with high photoacoustic conversion efficiency was prepared by optimizing the preparation process.Based on the performance of the prepared photoacoustic conversion composite in the laser ultrasound experiment,the influence of particle size,light absorption coefficient,and thermal diffusion coefficient of carbon black were studied for the photoacoustic conversion efficiency of the prepared photoacoustic conversion composite.And the experimental results and the simulation results can completely correspond.The CB-PDMS composites prepared according to the simulation optimization results show high photoacoustic conversion efficiency(up to3.44×10^-3,which is higher than the reported materials such as Gold NPs and Solution CNT).This carbon material composite model can be used as a general technology in the optimization research of the same type of composite materials,providing tools for designing composite photoacoustic conversion materials.