Preparation Of Neutron Shielding Material Based On Foam Ceramics From Fly Ash

Neutron shielding materials play an important role in the field of nuclear science and technology and are hot topics in research.At present,several kinds of neutron shielding materials commonly used have the disadvantages of high cost,complicated process and weak mechanical properties.In this regard,this paper proposes a neutron shielding material with foam ceramics as the skeleton with low cost,high temperature resistance,light weight,strong corrosion resistance and excellent mechanical properties.The specific research contents are as follows:In this paper,the neutron shielding material with reticulated porous ceramics as the skeleton is prepared by recycling the process waste fly ash.The reticulated porous ceramics were prepared by adding andalusite and alumina to the fly ash,and the reticulated porous ceramics were prepared by the precursor polyurethane impregnation method.The physical properties,microstructure and phase composition were characterized.The suitable matrix material ratio was determined to be 20wt% fly ash,20wt% andalusite,50wt% alumina and 10wt% kaolin,and the additive content of the base slurry was studied to determine the optimum addition amount of the slurry dispersant WSM,binder CL and thickener CMC: 1.1wt%,3.5wt% and 0.1wt%.The mechanical properties of the reticulated porous ceramics were further improved by vacuum secondary impregnation technology.The physical properties,microstructure and phase composition were compared to determine the suitable vacuum secondary impregnation.After the impregnation raw materials were determined,the thermal expansion coefficient of the matrix and the impregnated slurry was adjusted by controlling the raw material ratio of the vacuum impregnated slurry and the particle size of the raw material,and the mechanical properties of the residual ceramics and the effect of thermal shock stability were studied based on the residual stress calculation model.Finally,the prepared reticulated porous ceramics skeleton was filled with boron carbide micropowder and packaged to obtain a novel neutron shielding material.Monte Carlo simulation and neutron shielding performance test were carried out to verify that the shielding performance of the neutron shielding was better than 20 wt% boron-containing polyethylene...