苯基硅橡胶/硅氮陶瓷前驱体复合绝热层烧蚀机理  

Ablative properties and mechanisms of PMPS / PNS-3 silicon rubber compositive material under oxyacetylene flame

作　　者：周传健[1] 张惠[1] 周凯运[1] 张晨[1] 陈国文[1] 龙腾[1] 马琳[1] 牟秋红[2] 刘月涛[2] 

机构地区：[1]山东大学材料科学与工程学院,济南250061 [2]山东省科学院新材料所,济南250014

出　　处：《固体火箭技术》2015年第4期566-572,共7页Journal of Solid Rocket Technology

基　　金：山东省中青年科学家奖励基金(BS2010CL026)

摘　　要：采用甲基苯基聚硅氧烷(PMPS)与聚硅氮烷PNS-3为复合基体,气相法白炭黑和炭纤维为填充材料,制备了有机硅耐烧蚀复合材料,并采用氧乙炔焰烧蚀实验的方法研究了材料的烧蚀性能。在对烧蚀后的材料形貌SEM分析和采用XRD、FT-IR、EDS等方法进行了成分分析的基础上,发现加入聚硅氮烷后,苯基硅橡胶的烧蚀行为发生了变化,提出了氧化层、成炭层、陶瓷层、裂解层和基体五区域的新烧蚀模型,并对烧蚀机理进行了初步探讨。研究表明,绝热层在烧蚀过程中,氧化层主要组分是Si O2,起到隔绝氧化性气氛渗入的作用;氧化层下是新生成的耐高温、耐氧化的Si C陶瓷;成炭层坚硬致密起到了热防护的作用。Polymethylphenylsiloxane（ PMPS） elastomer ablative composite filled with polysilazane,fumed silica and carbon fibers was prepared and tested using an oxyacetylene torch. After the ablation,the material structure,composition and thermal-oxidative properties of the composite were analyzed using the SEM,FT-IR,XRD and EDS. The results show that a silica layer,a ceramic layer,a pyrolysis layer and the matrix are formed in turn by decomposition,ceramization and oxidation reactions of the virgin ablative composite. Aromatic carbon is formed in the porous pyrolysis and ceramic layers by the degradation of the silicone rubber matrix,which transforms into inorganic carbon in the zone close to the ceramic layer. Silicon carbide crystallite is produced in the ceramic layer. Oxidation of the compounds in the ceramic layer yields a silica layer,which is primarily composed of silica. The thermo-oxidative stabilities of the ablative layers are better than that of the virgin material as a result of the formation of dense carbon layer structure.

关 键 词：甲基苯基聚硅氧烷 耐烧蚀材料 氧化层 陶瓷层 成炭层 

分 类 号：V255.3[一般工业技术—材料科学与工程]