BP neural network was used in this study to model the porosity and the compressive strength of a gradient Al2Q-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The influences of the load applied on the e...BP neural network was used in this study to model the porosity and the compressive strength of a gradient Al2Q-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The influences of the load applied on the epispastic polystyrene template （F）, the centrifugal acceleration （V） and sintering temperature （T） on the porosity （P） and compressive strength （a） of the sintered products were studied by using the registered three-layer BP model. The accuracy of the model was verified by comparing the BP model predicted results with the experimental ones. Results show that the model prediction agrees with the experimental data within a reasonable experimental error, indicating that the three-layer BP network based modeling is effective in predicting both the properties and processing parameters in designing the gradient Al203-ZrO2 ceramic foam filter. The prediction results show that the porosity percentage increases and compressive strength decreases with an increase in the applied load on epispastic polystyrene template. As for the influence of sintering temperature, the porosity percentage decreases monotonically with an increase in sintering temperature, yet the compressive strength first increases and then decreases slightly in a given temperature range. Furthermore, the porosity percentage changes little but the compressive strength first increases and then decreases when the centrifugal acceleration increases.展开更多
泡沫铝内部多孔结构赋予其本身优异的吸能特性,可作为复合面板结构的夹芯吸能层。通过选择不同密度泡沫铝作为夹芯层,复合对位芳纶纤维板作为上下面板,研制一种轻质梯度的高强泡沫铝抗爆防护面板结构,解决了临时防御工事快速抗爆防护问...泡沫铝内部多孔结构赋予其本身优异的吸能特性,可作为复合面板结构的夹芯吸能层。通过选择不同密度泡沫铝作为夹芯层,复合对位芳纶纤维板作为上下面板,研制一种轻质梯度的高强泡沫铝抗爆防护面板结构,解决了临时防御工事快速抗爆防护问题。研究了在爆距0.8 m和1 kg TNT下匀质(H、M、L型)和梯度(MLL型、MML型、HML型、HMM型)泡沫铝夹芯面板结构的变形失效模式。研究结果表明:匀质泡沫铝呈现“正压溃”变形失效模式,即迎爆面穿孔后,匀质泡沫铝呈现由顶层至底层变形失效模式,而梯度泡沫铝呈现“负压溃”失效模式,即纤维复合面板烧焦破坏后,梯度泡沫铝呈现由L层→H层压溃失效模式。梯度泡沫铝夹芯面板的抗爆性能优于匀质泡沫铝,且在爆距0.8 m和1 kg TNT下尤以HMM型、匀质H型抗爆效果最好。展开更多
通过注浆成型结合真空发泡制备出具有明显梯度结构的多孔氮化硅陶瓷。该工艺在浆料中加入发泡剂,然后注入底部为石膏的模具中,抽真空保压并恒温保存,浆料在低压下会形成孔径梯度结构。研究发现,气压对样品的梯度结构有较明显影响,随着...通过注浆成型结合真空发泡制备出具有明显梯度结构的多孔氮化硅陶瓷。该工艺在浆料中加入发泡剂,然后注入底部为石膏的模具中,抽真空保压并恒温保存,浆料在低压下会形成孔径梯度结构。研究发现,气压对样品的梯度结构有较明显影响,随着气压由80 k Pa降低到9 k Pa,样品气孔率由59.01%提高到80.85%,当气压为80 k Pa时,样品无宏观梯度结构,随着气压的降低,梯度结构趋于明显。压汞法测试表明,9 k Pa气压制备的样品孔径分布比较分散,具有0.5、20、30、40、60、100和200μm等多种气孔孔径值。该工艺具有简易、廉价,孔径分布和气孔率可调的优点,可实现大尺寸、复杂形貌材料的制备,为梯度多孔材料的制备方法提供了新思路。展开更多
基金financially supported by the Natural Science Foundation of Liaoning Province(No.201102090)the Doctoral Initiating Project of Liaoning Province Foundation for Natural Sciences,China(No.20111068)+1 种基金the High School Development Plan for Distinguished Young Scholars of Liaoning Province Education Committee(No.LJQ2012056)the National High-Tech Research and Development Program of China("863"Program,No.2011AA060102)
文摘BP neural network was used in this study to model the porosity and the compressive strength of a gradient Al2Q-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The influences of the load applied on the epispastic polystyrene template （F）, the centrifugal acceleration （V） and sintering temperature （T） on the porosity （P） and compressive strength （a） of the sintered products were studied by using the registered three-layer BP model. The accuracy of the model was verified by comparing the BP model predicted results with the experimental ones. Results show that the model prediction agrees with the experimental data within a reasonable experimental error, indicating that the three-layer BP network based modeling is effective in predicting both the properties and processing parameters in designing the gradient Al203-ZrO2 ceramic foam filter. The prediction results show that the porosity percentage increases and compressive strength decreases with an increase in the applied load on epispastic polystyrene template. As for the influence of sintering temperature, the porosity percentage decreases monotonically with an increase in sintering temperature, yet the compressive strength first increases and then decreases slightly in a given temperature range. Furthermore, the porosity percentage changes little but the compressive strength first increases and then decreases when the centrifugal acceleration increases.
文摘泡沫铝内部多孔结构赋予其本身优异的吸能特性,可作为复合面板结构的夹芯吸能层。通过选择不同密度泡沫铝作为夹芯层,复合对位芳纶纤维板作为上下面板,研制一种轻质梯度的高强泡沫铝抗爆防护面板结构,解决了临时防御工事快速抗爆防护问题。研究了在爆距0.8 m和1 kg TNT下匀质(H、M、L型)和梯度(MLL型、MML型、HML型、HMM型)泡沫铝夹芯面板结构的变形失效模式。研究结果表明:匀质泡沫铝呈现“正压溃”变形失效模式,即迎爆面穿孔后,匀质泡沫铝呈现由顶层至底层变形失效模式,而梯度泡沫铝呈现“负压溃”失效模式,即纤维复合面板烧焦破坏后,梯度泡沫铝呈现由L层→H层压溃失效模式。梯度泡沫铝夹芯面板的抗爆性能优于匀质泡沫铝,且在爆距0.8 m和1 kg TNT下尤以HMM型、匀质H型抗爆效果最好。
文摘通过注浆成型结合真空发泡制备出具有明显梯度结构的多孔氮化硅陶瓷。该工艺在浆料中加入发泡剂,然后注入底部为石膏的模具中,抽真空保压并恒温保存,浆料在低压下会形成孔径梯度结构。研究发现,气压对样品的梯度结构有较明显影响,随着气压由80 k Pa降低到9 k Pa,样品气孔率由59.01%提高到80.85%,当气压为80 k Pa时,样品无宏观梯度结构,随着气压的降低,梯度结构趋于明显。压汞法测试表明,9 k Pa气压制备的样品孔径分布比较分散,具有0.5、20、30、40、60、100和200μm等多种气孔孔径值。该工艺具有简易、廉价,孔径分布和气孔率可调的优点,可实现大尺寸、复杂形貌材料的制备,为梯度多孔材料的制备方法提供了新思路。
