氟化乙丙烯薄膜单轴拉伸力学性能试验

对150μm厚氟化乙丙烯(FEP)薄膜沿MD和TD方向裁取的试样进行4种拉伸速度的单轴拉伸试验,得到相应的屈服强度、抗拉强度和断裂伸长率,并给出以应变速率为变量的线性拟合公式;进行3种拉伸应力的循环拉伸试验,得到每循环割线模量及残余应变;进行3种应力水平下的徐变试验,分析徐变发展趋势.结果表明:FEP薄膜的屈服强度、抗拉强度和断裂伸长率都随着应变速率的增大而增大;随着循环次数的增加,循环割线模量及残余应变趋于稳定;拉伸应力9MPa时材料产生明显徐变.试验结果对FEP薄膜工程设计应用具有参考价值.

Experimental Study of Uniaxial Tensile Mechanical Properties of Fluorinated Ethylene Propylene Foils

Abstract： A series of uniaxial mechanical property tests were conducted for the FEP foils（thickness：150 μm）and the specimens were cut from foils along the machine direction（MD）. The transverse direction（TD）. The yield strength, the tensile strength and the elongation at break were obtained from the uniaxial tensile tests by using four kinds of tensile speed. The linear fitting formulas through using the tensile strain rate. The variable were proposed. The analysis of the secant modulus and the residual strain per cycle were obtained via the uniaxial cyclic tensile tests by using three values of cycle stress. The analysis of creep development was conducted from the results of the creep tests by using three kinds of stresses. The results show that the yield strength, the tensile strength, the elongation at break of the FEP foils material are increased with the increase of tensile strain rate. The secant modulus and the residual strain remain stable with the increase of cyclic times. The large creep is observed in the stress of 9 MPa. The result of the tests can provide valuable reference for practical membrane engineering design of FEP foils.