【摘要】 对聚四氟乙烯、改性聚四氟乙烯在-50℃、-100℃、-196℃的压缩回弹性能进行试验研究，分析了温度对垫片压缩回弹性能的影响。结果表明，垫片压缩率随着温度的降低而减小，回弹率在-100℃达到最大。同等预紧应力下，介质压力越大，泄漏率越大。通过试验研究了-100℃时介质压力、预紧应力对2种垫片泄漏率的影响，得到了泄漏率与介质压力、预紧应力的关系曲线。相同介质压力下，预紧应力越大，泄漏率越小。对传统泄漏模型进行了改进，改进后的泄漏模型预测值与试验结果更为接近。研究结果可为低温工况下聚四氟乙烯密封材料的应用提供参考。更多还原

【Abstract】 The compression and resilience properties of polytetrafluoroethylene and modified polytetrafluoroethylene gaskets at-50 ℃,-100℃, and-196 °C were studied through experiments. The results show that the gasket compression rate decreases with the decrease in temperature, and the resilience rate reaches the maximum at-100 °C. The effect of temperature on the compression and resilience of the gaskets was analyzed,and the effects of medium pressure and preload stress on the leakage rate of two kinds of gaskets at-100 °C were experimentally investigated. The relationship of the leakage rate with medium pressure and preload stress was obtained.Under the same preload stress, a greater medium pressure means a greater leakage rate, and under the same medium pressure, a greater preload stress indicates a smaller leakage rate. The traditional leakage model is improved, and the predicted value of the improved leakage model is closer to the experimental results. The research results provide a reference for the application of polytetrafluoroethylene sealing materials under low temperature conditions.更多还原