国防科技大学学报
國防科技大學學報
국방과기대학학보
JOURNAL OF NATIONAL UNIVERSITY OF DEFENSE TECHNOLOGY
2014年
5期
149-154
,共6页
韩笑%邢欣%王军%程海峰
韓笑%邢訢%王軍%程海峰
한소%형흔%왕군%정해봉
碳化硅%热电性能%先驱体转化法%纳米复合材料
碳化硅%熱電性能%先驅體轉化法%納米複閤材料
탄화규%열전성능%선구체전화법%납미복합재료
silicon carbide%thermoelectric properties%polymer-derived method%nanocomposites
以聚碳硅烷和锑改性聚硅烷为先驱体,利用先驱体转化SiC材料的富余自由碳高温石墨化的微观结构演变特点,采用热压烧结、先驱体浸渍-裂解法以及退火工艺制备出先驱体转化SiC纳米复合材料。采用SEM、TEM、XRD和Raman等测试手段表征和分析了相组成和微观结构,讨论了样品的热导率、电导率和塞贝克系数等热电参数随温度变化关系。研究表明,所得致密SiC纳米复合材料为n型热电材料。由于纳米石墨的作用,材料热导率抑制在4~8W/(m·K)范围。1600℃退火处理能够降低热导率,同时提高电导率和塞贝克系数绝对值,使先驱体转化法得到的SiC纳米复合材料无量纲热电优值ZT达到0.0028(650℃),高于其他已报道的致密SiC/C复合材料和纳米复合材料体系。
以聚碳硅烷和銻改性聚硅烷為先驅體,利用先驅體轉化SiC材料的富餘自由碳高溫石墨化的微觀結構縯變特點,採用熱壓燒結、先驅體浸漬-裂解法以及退火工藝製備齣先驅體轉化SiC納米複閤材料。採用SEM、TEM、XRD和Raman等測試手段錶徵和分析瞭相組成和微觀結構,討論瞭樣品的熱導率、電導率和塞貝剋繫數等熱電參數隨溫度變化關繫。研究錶明,所得緻密SiC納米複閤材料為n型熱電材料。由于納米石墨的作用,材料熱導率抑製在4~8W/(m·K)範圍。1600℃退火處理能夠降低熱導率,同時提高電導率和塞貝剋繫數絕對值,使先驅體轉化法得到的SiC納米複閤材料無量綱熱電優值ZT達到0.0028(650℃),高于其他已報道的緻密SiC/C複閤材料和納米複閤材料體繫。
이취탄규완화제개성취규완위선구체,이용선구체전화SiC재료적부여자유탄고온석묵화적미관결구연변특점,채용열압소결、선구체침지-렬해법이급퇴화공예제비출선구체전화SiC납미복합재료。채용SEM、TEM、XRD화Raman등측시수단표정화분석료상조성화미관결구,토론료양품적열도솔、전도솔화새패극계수등열전삼수수온도변화관계。연구표명,소득치밀SiC납미복합재료위n형열전재료。유우납미석묵적작용,재료열도솔억제재4~8W/(m·K)범위。1600℃퇴화처리능구강저열도솔,동시제고전도솔화새패극계수절대치,사선구체전화법득도적SiC납미복합재료무량강열전우치ZT체도0.0028(650℃),고우기타이보도적치밀SiC/C복합재료화납미복합재료체계。
Taking polycarbosilane and antimony-modified polysilane for precursors and drawing lessons from the transformation process of high temperature graphitization of spare free carbon in SiC materials,the polymer-derived SiC nanocomposites were prepared by employing hot-press sintering,precursor infiltrating-cracking methods and annealing.The phases and microstructures were characterized and analyzed by using SEM, TEM,XRD and Raman test methods.The thermoelectric parameters of samples,such as thermal conductivity,electrical conductivity and Seebeck coefficient,were studied.Results show that the dense SiC nanocomposites acquired are n-type thermoelectric materials.The thermal conductivity is suppressed at the range of 4~8W/(m·K)due to the function of nano-graphite.At the annealing temperature of 1600°C,the thermal conductivity reduces while both the electrical conductivity and the Seebeck coefficient increase,and ZT value of SiC nanocomposites derived from precursor reaches to 0.0028(650°C),which is higher than that of SiC/C composites or nanocomposites ever reported.