γ射线辐照聚四氟乙烯复合材料的结构和摩擦磨损性能研究  

Effect of Gamma Irradiation on Structure and Tribological Properties of PTFE Composites

作　　者：王超[1] 丛国辉 许雪飞[1] 张翊勋 王廷梅[1] 王学灵 王齐华[1] WANG Chao;CONG Guohui;XU Xuefei;ZHANG Yixun;WANG Tingmei;WANG Xueling;WANG Qihua(Key Laboratory of Science and Technology on Wear and Protection of Materials,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Gansu Lanzhou 730000,China;National Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment,China Nuclear Power Engineering Co,Ltd,Guangdong Shenzhen 518172,China)

机构地区：[1]中国科学院兰州化学物理研究所中国科学院材料磨损与防护重点实验室,甘肃兰州730000 [2]中广核工程有限公司核电安全监控技术与装备国家重点实验室,广东深圳518172

出　　处：《摩擦学学报》2021年第4期503-511,共9页Tribology

基　　金：中国科学院青年创新促进会资助项目(2020417),中国科学院西部之光项目;国家重点研发计划项目(2018YFB2000802);国家自然科学基金航天先进制造项目(U1737204)资助。

摘　　要：通过γ射线辐照聚苯酯改性聚四氟乙烯(PTFE/POB)复合材料,利用红外光谱、X射线衍射、DSC等对辐照前后材料的化学组成、结晶结构等进行了表征,并与γ射线辐照纯PTFE材料作对比,考察了热稳定性能、拉伸性能和摩擦磨损性能.结果表明:γ射线辐照并未造成PTFE/POB材料的化学组成和热稳定性能的明显变化,但使得PTFE分子量降低,结晶度增大;相比纯的PTFE材料,POB的加入一定程度上提高了PTFE的抗辐照能力,延缓了PTFE分子量下降程度和再结晶化能力.辐照对PTFE/POB材料的耐磨性能影响并不显著,但摩擦系数均有不同程度的降低,且随着辐照剂量的增大,呈现先增大后减小的变化趋势,这与辐照后PTFE的分子量、结晶度及带晶尺寸变化,以及POB自身的抗辐照能力等密切相关.In this paper,the tribological behavior of PTFE and its composites after gamma ray irradiation was studied.The effects of irradiation on the chemical structure,heat resistance and tensile properties of the materials were mainly investigated,so as to establish the correlation between the structure change and tribological properties of PTFE under irradiation,and provide guidance for the design of PTFE sealing materials for nuclear power plants. Poly(phenylene terephthalate) modified polytetrafluoroethylene(PTFE/POB) composites were irradiated by gamma-ray with dose of1 000 Gy,1 500 Gy,2 200 Gy,and 3 000 Gy. The chemical composition and crystal structure of the materials before and after irradiation were characterized by infrared spectroscopy,X-ray diffraction and differential scanning calorimetry.The thermal stability,tensile properties and tribological properties of the materials were compared with those of irradiated pure PTFE. The results show that the chemical composition and thermal stability of PTFE/POB materials are not significantly changed under irradiation,but the molecular weight of PTFE decreases sharply,and the small molecular chains spontaneously form crystalline phase,leading to the increase of crystallinity. Compared with pure PTFE,the addition of POB improves the radiation resistance of PTFE to a certain extent,and delays the decrease of molecular weight and recrystallization ability of PTFE. The results showed that the tensile strength of PTFE and PTFE/POB decreased significantly after irradiation,but for PTFE/POB,with the increase of irradiation dose,the decreasing trend of the tensile strength of PTFE/POB was not significant,but gradually stabilized. The effect of irradiation on the elongation at break of PTFE and PTFE/POB is complex. The elongation at break of pure PTFE increases first and then decreases with the increase of irradiation dose,while the elongation at break of PTFE/POB decreases with the increase of irradiation dose. The effect of irradiation on the wear resistance of PTFE/POB is

关 键 词：聚四氟乙烯 Γ射线辐照 结晶度 分子量 摩擦磨损 

分 类 号：TH117.3[机械工程—机械设计及理论]