耐温屏蔽复合材料的研制及性能研究

Study on the development and performance of heat-resistant radiation shielding composites

为满足核电站、乏燃料存储设施等对防护材料的耐温性、热稳定性、耐辐照性能等要求,研制四官能环氧树脂基(AGA型)耐温屏蔽复合材料。首先对基体材料的热稳定性进行分析,由热重分析(thermogravimetric analysis,TG)曲线得到其起始分解温度为353.5℃,200℃恒温储存170 h后,基体材料失重1.22%。动态热机械性能分析(dynamic thermomechanical analysis,DMA)表明,随着钨(W)含量的增加,AGA型耐温屏蔽复合材料的玻璃化温度向高温区移动并且峰型变宽。用60 Co放射源辐照50 kGy剂量,当AGA型耐温屏蔽复合材料的W含量10.5 wt%,B 4C含量3 wt%时,其辐照前后冲击强度均为最优。用252 Cf中子源测试2 cm厚AGA型耐温屏蔽复合材料的屏蔽性能,当加入3 wt%的B 4C时,AGA-4耐温屏蔽复合材料的快中子透射率为50.00%。实验结果表明,AGA型耐温屏蔽复合材料具有一定的耐温性和耐辐照性能,并且密度较小。

Background:In order to meet the requirements in performance of heat-resistant,thermal stability,radiation resistance etc of radiation shielding materials used in nuclear power plant and spent fuel storage.Purpose:AGA heat-resistant shielding composites were developed.Methods:The thermal stability of the matrix material was analyzed by using thermogravimetric analysis(TGA).Dynamic Thermomechanical Analysis(DMA)was used to analyze the glass transition temperature of AGA composites.Irradiation resistance test was carried out under 60 Co sources and its shielding performance was tested with a 252 Cf neutron source.The Results:From the TG curves,the initial decomposition temperature was 353.5℃.And after the constant temperature storage at 200℃for 170 h,the weightloss of the matrix material was 1.22%.DMA showed that the glass transition temperature of the shielding composites moved to the higher temperature area and the peak type widens as the W content increases.The impact strength of the AGA heat-resistant shielding composite was optimal with a W content of 10.5 wt%and a B 4C content of 3 wt%.When 3 wt%B 4C was added,the fast neutron transmission of the AGA-4 heat-resistant shielding composite with 2 cm thick was 50.00%.Conclusions:AGA heat-resistant shielding composites has certain heat-resistant and irradiation resistance,and low density.