【作者】 敖庆波；

【导师】 汤慧萍；

【作者基本信息】 东北大学 ， 材料学， 2008， 硕士

【摘要】 吸声用烧结FeCrAl纤维多孔材料是金属纤维领域一个新的研究方向。烧结FeCrAl纤维多孔材料兼具FeCrAl合金和多孔结构的特点,具有诸多独特优点,如耐高温、抗氧化、耐热腐蚀、耐气流冲击性能好、使用寿命长、易加工、有效孔隙度高、性能稳定、结构具有可设计性等,同时具有稳定且优良的吸收高强度噪声的能力,因此,烧结FeCrAl纤维多孔材料是优异的航空发动机扇涡轮腔体高温声衬材料,在航空航天、国防等特殊环境中具有其它材料难以比拟的吸收高强度噪声性能。本文采用真空烧结法制备不同孔隙性能的FeCrAl纤维多孔材料,可有效控制材料的孔隙结构参数,同时还可有效避免FeCrAl纤维毡烧结时的组分挥发；重点研究了烧结FeCrAl纤维多孔材料的吸声性能,详细分析了烧结FeCrAl纤维多孔材料的声学特性参数及吸声性能参数,结果表明,在常声压和高声强两种环境中烧结FeCrAl纤维多孔材料的孔隙度、厚度及空腔三种结构参数对材料吸声性能有显著影响；为改善烧结FeCrAl纤维多孔材料的中低频吸声性能,本文对材料的孔隙结构进行了设计组合,研究了2-3层组合结构的吸声特性,得出按孔隙度由高到低排列,且各层厚度越厚材料的吸声性能越好的结论。高声强条件下(100-140dB)单层和组合结构的吸声性能研究结果表明,在此条件下的材料吸声性能不随声压级的变化而变化,说明烧结FeCrAl纤维多孔材料具有很好的吸收高声强噪声的能力。本文是在国家“973”项目“超轻多孔和结构创新构型的多功能化基础研究”(项目编号为：2006CB601200)资助下完成的。更多还原

【Abstract】 Sintered FeCrAl fibrous porous materials used in sound absorption field is a new study orientation in metal fibrous technology area. Sintered FeCrAl fibrous porous materials have the characteristics of FeCrAl alloy and porous structure, and they possess lots of special advantages, such as high temperature resistance, anti-oxidation, hot corrosion resistant, good performance of flow impact resistant, long service life, easily forming, higher effective porosity, stable performance, designable of the structure, above all, sintered FeCrAl fibrous porous materials have stable and excellent properties to absorb the high intensity noise. Therefore, sintered FeCrAl fibrous porous materials can be used as high temperature liners in the turbofan cavity of aero-engine. Compared with other materials, sintered FeCrAl fibrous porous materials have excellent performance in sound absorption. It is suitable for absorbing high intense noise in special environment of space and defense area.In this dissertation, sintered FeCrAl fibrous porous materials with different porosity were prepared by using vacuum sintering technology. Parameters of pore structure were effectively controlled during this process and component volatilization in FeCrAl fibrous porous materials can be also avoided. This paper aimed at studing sound absorption performance of sintered FeCrAl fibrous porous materials. The parameters of acoustics character and sound absorption performance were analyzed in detail. The results indicated that porosity, thickness and cavity play an important role in sound absorption under ordinary acoustic pressure and high sound intensity conditions. In order to improve the sound absorption characteristics for sintered FeCrAl fibrous porous materials under low and middle frequency, the composite structure with 2-3 layers were redesigned. The results show that the arrangement of composite structure in porosity order from high to low is the best. The thicker the every layer thickness of the structure is, the better the sound absorption performance is. The sound absorption characteristics of monolayer and gradient composite structure under ordinary acoustic pressure and high sound intensity conditions (100-140dB) show that the sound absorption characteristic was constant with the change of acoustic pressure levels. It shows that sintered FeCrAl fibrous porous materials have good ability to absorb high intensity noise. The research of this dissertation is funded by National 973 of China (project No. 2006CB601200).更多还原