MgO过渡层对PET基SiO2薄膜结合强度的影响

采用磁控溅射镀膜机制备了含有MgO过渡层的SiO2/MgO/PET复合薄膜,并通过垂直拉伸法测量了所得复合薄膜的结合强度,探讨了过渡层对复合膜结合强度的影响规律.结果表明:在PET基材与SiO2膜层之间引入MgO过渡层后,SiO2/MgO/PET复合膜的结合力较SiO2/PET复合膜提高了80%以上;MgO过渡层的制备参数对SiO2/MgO/PET复合膜的结合强度有着重要影响,结合强度随本底真空度的增高而增大,随射频功率、氩气流量、溅射时间的增大而呈现先增大后减小的变化规律;4个制备参数对结合强度的影响程度由大到小依次是本底真空度、射频功率、氩气流量和溅射时间;4个制备参数较优的水平组合为本底真空度0.5×10-3Pa、射频功率250 W、溅射时间12 min、氩气流量20 mL·min-1.

Effects of MgO Interlayer on Adhesion Strength of PET Substrate SiO2 Film

At present the foundation pit supporting pile soil pressure calculation mostly applies the classical earth pressure theory or normative experience method, which deduced under the limit equilibrium state, and is significantly different from the foundation pit engineering under non-limit state of soil. Based on the previous research results, applies the method of level-layer analysis and combining with the reasonable assumption to deduce the calculation formula of quasi active earth pressure of non-limit state between initial state and limit state, and improves the method of level-layer analysis. Through the analysis of the foundation pit engineering examples, it shows that the obtained quasi active earth pressure value is basically consistent with the actual measured earth pressure, and the caculating result of the method of level-layer analysis relatively larger than the consequence of Rankine active earth pressure, but it is less than the static earth pressure value, which in line with the non-limit state law of earth pressure. It also illustrated reasonableness of the previous assumptions and correctness of quasi- active earth pressure formula.