热压工艺对循环拉伸下飞艇蒙皮材料的能量耗散与残余应变特性的影响

Influence of hot pressing process on energy dissipation and residual strain characteristics of airship envelope material under cyclic stretching

为探究热压复合工艺参数对飞艇蒙皮材料的能量耗散与残余应变特性的影响机制,本文以聚氟乙烯(PVF)膜为耐气候层,TPU膜为阻氦层,聚芳酯Vectran纤维机织平纹布为承力层,TPU胶膜为黏结层,通过热压复合的方式制备多种热压工艺参数下的飞艇蒙皮材料,并对其进行循环加载-卸载后的力学性能测试,分析了热压温度和热压时间对耗散能和残余应变的影响规律,并提出了理论公式。结果表明:热压温度和热压时间对飞艇蒙皮材料的能量耗散与残余变形特性的影响的变化规律相同,且拟合方程的拟合程度良好,系数与热压温度和热压时间呈正相关;材料的能量耗散与残余应变特性的变化规律不仅取决于热压工艺,同时还与循环加载-卸载次数密切相关,并表现出两段式线性特性;通过比较在不同热压工艺参数下制备的飞艇蒙皮材料经循环加载-卸载后产生的耗散能与残余应变的大小,得出最优制备工艺为:热压温度为160℃,热压时间为600 s。

In order to explore the influence mechanism of the process parameters of the hot-pressing compound on the energy dissipation and residual strain characteristics of the airship envelope material,the polyvinyl fluoride(PVF)film is used as the weather resistant layer,the TPU film as the helium barrier layer,and the polyarylate Vectran fiber woven plain weave as load-bearing layer,and the TPU film as the adhesive layer.The airship envelope materials with various hot-pressing process parameters were prepared by hot-pressing composite method,and the mechanical properties of airship envelope materials are tested and analyzed after cyclic loading-unloading.The influence of hot pressing temperature and hot pressing time on dissipation energy and residual strain is analyzed,and theoretical formulas are proposed.The results show that the hot-pressing temperature and hot-pressing time have the same influence on the energy dissipation and residual strain characteristics of the airship envelope materials,and the fitting degree of the fitting equation is good,and the coefficients are positively correlated with the hot-pressing temperature and hot-pressing time.The energy dissipation and residual strain characteristics of the materials show a two-stage linear characteristic,which is not only dependent on the hot pressing process,but also closely related to the times of cyclic loading and unloading.By comparing the dissipated energy and residual strain of the airship envelope materials prepared under different hot pressing process parameters after cyclic loading and unloading,the optimal preparation process was obtained as follows:Hot pressing temperature is 160℃,hot pressing time is 600 s.