随着核电的发展，其极端的环境对绝缘部件提出了更高的要求。玻璃纤维增强硅树脂由于优异的物理化学性能，被广泛应用于高温高电压的工况下。为了提高硅树脂的固化度并确保制品性能与材料特性相匹配，以压水堆(PWR)核电机组中控制棒驱动机构（CRDM）的磁轭线圈骨架作为玻纤增强硅树脂的模压成型制品，通过热重分析法和差示扫描量热法研究了硅树脂模塑料的固化热行为，优化了制品的模压工艺参数，采用热重分析和拉伸测试表征了制品的热稳定性和力学性能，研究了后固化参数对制品性能的影响。结果表明，与常温相比，175 ℃后固化24 h的制品抗拉强度增幅最大，提高了122%，热失重质量分数最小，减少了82.25%。硅树脂的失重固化和热氧化降解是影响制品性能的原因。磁轭线圈骨架模压成型工艺参数为模具温度130 ℃、成型压力50 MPa、保压时间10 min、固化温度175 ℃、烘烤时间24 h。成型制品通过了核电机组的热老化性能测试验证。
With the development of nuclear power, extreme environment raised higher requirements for insulation parts. Fiberglass reinforced silicone resin (FRSR) is widely used in high-temperature and electromagnetic working environments due to its excellent physical and chemical properties. In order to improve the curing degree of silicone resin and ensure that the product performance matches material characteristics. The yoke coil bobbin of the control rod drive mechanism (CRDM) in the pressurized water reactor (PWR) nuclear power plant was used as compression-molded product of FRSR. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to analyze the curing thermal behavior of silicone resin molding compounds and optimized the compression process parameters of the bobbin. The thermal stability and mechanical properties were analyzed by TGA and tensile tests, and the effect of post-curing parameters on bobbin performance was studied. Experimental results reveal that, compared with normal temperature, the coil bobbin of post-curing at 175 ℃ for 24 h has the greatest increase of tensile strength, reaching 122% and the mass fraction of thermal mass loss is the least, reducing 82.25%. The weightlessness curing and thermal oxidative degradation of silicone resin affect the performance of the product. The optimal process parameters for compression molding yoke coil bobbins are molding temperature of 130 °C, molding pressure of 50 MPa, pressure holding time of 10 min, the post-curing temperature of 175 °C, and post-curing time of 24 h. The molded product can pass the thermal aging performance test verification of the nuclear power unit.