Abstract Continuous alumina fibers were prepared using sol-gel dry spinning-high temperature sintering method. During the pre-sintering and high-temperature sintering of the precursor fibers, the self-designed tensioning sintering device was used to apply axial tension to the fibers. The effects of tension on the thermal decomposition, phase transformation, structural evolution and properties of alumina fibers during the sintering process were investigated by characterizing the morphology, composition and structure of alumina fibers and comparing with the fibers sintered freely (without tension).The results show that the application of tension during sintering can significantly increase the straightness of pre-sintered and sintered fibers, and promote the decomposition and removal of residues in precursor fibers. Tensile sintering can inhibit the axial shrinkage of fibers, increase the radial shrinkage, and promote the transformation of γ-Al2O3 to α-Al2O3. Tensile sintering can also improve the grain morphology and pore distribution of fibers, promote grain growth and shrinkage, and removal of intergranular pores, and promote the densification of fibers. Compared with free sintering, the application of 0.9 MPa axial tension during sintering increases the average tensile strength of alumina fibers sintered at 1500 ℃ for 3 min by 231%, from 0.35 GPa to 1.16 GPa.
PENG Shaoheng,YAO Shuwei,WANG Juan, et al. Microstructure evolution of continuous alumina fiber under tensile sintering[J]. Materials Science and Engineering of Powder Metallurgy, 2022, 27(5): 542-549.
[1] ARMANI C J, RUGGLES-WRENN M B, HAY R S, et al. Creep and microstructure of Nextel (TM) 720 fiber at elevated temperature in air and in steam[J]. Acta Materialia, 2013, 61(16): 6114-6124. [2] 李泉, 宋慎泰. 氧化铝基连续陶瓷纤维的发展现状[J]. 耐火材料, 2006(1): 50-52. LI Quan, SONG Shentai.Development of alumina based continous ceramic fibers[J]. Refractories, 2006(1): 50-52. [3] 汪家铭, 孔亚琴. 氧化铝纤维发展现状及应用前景[J]. 高科技纤维与应用, 2010, 35(4): 49-54. WANG Jiangming, KONG Yaqin.Development present condition and application prospect of alumina fiber[J]. Hi-Tech Fiber & Application, 2010, 35(4): 49-54. [4] 陈代荣, 韩伟健, 李思维, 等. 连续陶瓷纤维的制备、结构、性能和应用:研究现状及发展方向[J]. 现代技术陶瓷, 2018, 39(3): 151-222. CHEN Dairong, HAN Weijian, LI Siwei, et al.Fabrication, microstructure, properties and applications of continunous ceramic fibers: a review of present status and further directions[J]. Advanced Ceramics, 2018, 39(3): 151-222. [5] HAY R S, FAIR G E, TIDBALL T.Fiber strength after grain growth in Nextel 610 alumina fiber[J]. Journal of the American Ceramic Society, 2015, 98(6): 1907-1914. [6] HAY R S, FAIR G E, KELLER K A, et al.Determination of 3-D alumina grain orientation, size, shape, and growth kinetics from 2-D data in Nextel 610 fibers[J]. Journal of the American Ceramic Society, 2015, 98(7): 2295-2306. [7] BUNSELL A R, BERGER M H.Fine diameter ceramic fibres[J]. Journal of the European Ceramic Society, 2000, 20(13): 2249-2260. [8] CANTONWINE P E.Strength of thermally exposed alumina fibers. Part I: single filament behavior[J]. Journal of Materials Science, 2003, 38(3): 461-470. [9] WILSON D M, VISSER L R.High performance oxide fibers for metal and ceramic composites[J]. Composites: Part A Applied Science and Manufacturing, 2001, 32(8): 1143-1153. [10] 乔健, 刘和义, 崔宏亮, 等. 连续氧化铝纤维的制备及应用[J]. 中国陶瓷, 2015, 51(8): 1-5. QIAO Jian, LIU Heyi, CUI Hongliang, et al.Synthesis of continuous alumina fiber and its applications[J]. China Ceramics, 2015, 51(8): 1-5. [11] LIANG C, LIU W, LIU Q, et al.The formation of core-sheath structure and its effects on thermal decomposition and crystallization of alumina fibers[J]. Ceramics International, 2021, 47(4): 5145-5155. [12] SCHMUECKER M, MECHNICH P.Microstructural coarsening of Nextel (TM) 610 fibers embedded in alumina-based matrices[J]. Journal of the American Ceramic Society, 2008, 91(4): 1306-1308. [13] CHANDRADASS J, BAE D S, BALASUBRAMANIAN M.Synthesis and characterization of sol-gel alumina fiber by seeding α-alumina through extended ball milling[J]. Materials and Manufacturing Processes, 2008, 23(8): 786-790. [14] MCARDLE J L, MESSING G L.Transformation, microstructure development, and densification in α-Fe2O3-seeded boehmite- derived alumina[J]. Journal of the American Ceramic Society, 1993, 76(1): 214-222. [15] SCHMUECKER M, FLUCHT F, MECHNICH P.Degradation of oxide fibers by thermal overload and environmental effects[J]. Materials Science and Engineering A, 2012, 557: 10-16. [16] LI X, XU H, WANG Q, et al.Control of continuous α-Al2O3 fibers by self-seeding and SiO2-Sol doping[J]. Ceramics International, 2019, 45(9): 12053-12059. [17] LI X, SU X, XIAO H, et al.Continuous α-Al2O3 fibers grown by seeding with in-situ suspension[J]. Ceramics International, 2020, 46(10): 15638-15645. [18] CHATTERJEE M, NASKAR M K, CHAKRABARTY P K, et al.Sol-gel alumina fibre mats for high-temperature applications[J]. Materials Letters, 2002, 57(1): 87-93. [19] 孙君, 熊喜科, 戴礼兴. 交替张力热处理对聚对苯二甲酸丙二醇酯纤维弹性的提升[J]. 高分子材料科学与工程, 2019, 35(12): 93-98. SUN Jun, XIONG Xike, DAI Lixing.Increase of elasticity of poly (trimethylene terephthalate) fiber through heat-treatment with alternating tension[J]. Polymer Materials Science and Engineering, 2019, 35(12): 93-98. [20] 康宸. PAN取向分子热松弛行为控制研究[D]. 北京: 北京化工大学, 2018. KANG Chen.Study on controlling thermal relaxation behavior of PAN oriented molecules[D]. Beijing: Beijing University of Chemical Technology, 2018. [21] 宋云飞, 宋邦琼, 刘斌, 等. 高温碳化张力对碳纤维性能影响[J]. 化工科技, 2015, 23(3): 22-24. SONG Yunfei, SONG Bangqiong, LIU Bin, et al.Effects of high temperature carbonized tension on performance of carbon fiber[J]. Science and Technology in Chemical Industry, 2015, 23(3): 22-24. [22] 郑春满, 李效东, 楚增勇, 等. 张力对聚碳硅烷纤维热解过程和SiC纤维性能的影响[J]. 硅酸盐学报, 2005(6): 688-692. ZHENG Chunman, Li Xiaodong, Chu Zengyong, et al.Effect of tension on pyrolysis process of polycarbosilane fiber and properties of SiC fiber[J]. Journal of the Chinese Ceramic Society, 2005(6): 688-692. [23] 李萌. 溶胶凝胶法制备连续氧化铝纤维的基础研究[D]. 长沙:国防科学技术大学, 2011. LI Meng.Research of preparation of continuous alumina fibers by sol-gel method[D]. Changsha: National University of Defense Technology, 2011. [24] CHENG M, LIU W, YAO S, et al.Comparing the phase transformation of continuous alumina fiber and xerogels derived from the same precursor[J]. Journal of Sol-Gel Science and Technology, 2021, 99(1): 169-177. [25] GAO Y, CHENG M, LIU Q, et al.Thermal decomposition of aluminum carboxylates based precursor for alumina fibers[J]. Materials Research Express, 2019, 6(11): 115109. [26] LIU J, MA Y, LIU W, et al.Preparation of alumina precursor sols with a high solid content for alumina fibers[J]. Materials Research Express, 2019, 6(4): 045207.
2022, Vol. 27 
