粉末冶金材料科学与工程
粉末冶金材料科學與工程
분말야금재료과학여공정
POWDER METALLURGY MATERIALS SCIENCE AND ENGINEERING
2014年
3期
459-466
,共8页
陆琼%王晓虹%朱高明%吴光志%冯培忠
陸瓊%王曉虹%硃高明%吳光誌%馮培忠
륙경%왕효홍%주고명%오광지%풍배충
金属间化合物%二硅化钼%合金化%燃烧合成%组织结构
金屬間化閤物%二硅化鉬%閤金化%燃燒閤成%組織結構
금속간화합물%이규화목%합금화%연소합성%조직결구
intermetallics%molybdenum disilicide%alloying%combustion synthesis%microstructure
以Mo、Nb、Si、Al元素粉末为原料,采用燃烧合成法制备名义成分分别为(Mo0.97Nb0.03)(Si0.97Al0.03)2、(Mo0.94Nb0.06)(Si0.97Al0.03)2、(Mo0.91Nb0.09)(Si0.97Al0.03)2与(Mo0.88Nb0.12)(Si0.97Al0.03)2等4种不同化含量的合金,研究其燃烧合成行为,分析燃烧合成过程中粉末压坯的燃烧模式、燃烧温度、燃烧波前沿蔓延速率以及产物组成。结果表明:随 Nb 含量增加,燃烧合成反应模式由螺旋燃烧逐渐转变为稳态燃烧。添加 Nb、Al 后,合金的最高燃烧温度升高,并随Nb含量增加呈现先升高后降低的变化趋势,其中(Mo0.91Nb0.09)(Si0.97Al0.03)2的燃烧温度最高,达到1924 K,但燃烧波蔓延速率随Nb含量增加而逐渐降低。XRD结果表明:(Mo0.97Nb0.03)(Si0.97Al0.03)2合金主要由 MoSi2构成,含有少量 Mo(SiAl)2和 Mo5Si3;(Mo0.94Nb0.06)(Si0.97Al0.03)2中开始出现 NbSi2相,(Mo0.91Nb0.09)(Si0.97Al0.03)2和(Mo0.88Nb0.12)(Si0.97Al0.03)2合金中Mo5Si3的衍射峰强度进一步降低,而NbSi2的衍射峰略有增强,因而添加Nb有利于形成C40结构的NbSi2,同时抑制Mo5Si3的产生。SEM观察表明合金为多孔结构。
以Mo、Nb、Si、Al元素粉末為原料,採用燃燒閤成法製備名義成分分彆為(Mo0.97Nb0.03)(Si0.97Al0.03)2、(Mo0.94Nb0.06)(Si0.97Al0.03)2、(Mo0.91Nb0.09)(Si0.97Al0.03)2與(Mo0.88Nb0.12)(Si0.97Al0.03)2等4種不同化含量的閤金,研究其燃燒閤成行為,分析燃燒閤成過程中粉末壓坯的燃燒模式、燃燒溫度、燃燒波前沿蔓延速率以及產物組成。結果錶明:隨 Nb 含量增加,燃燒閤成反應模式由螺鏇燃燒逐漸轉變為穩態燃燒。添加 Nb、Al 後,閤金的最高燃燒溫度升高,併隨Nb含量增加呈現先升高後降低的變化趨勢,其中(Mo0.91Nb0.09)(Si0.97Al0.03)2的燃燒溫度最高,達到1924 K,但燃燒波蔓延速率隨Nb含量增加而逐漸降低。XRD結果錶明:(Mo0.97Nb0.03)(Si0.97Al0.03)2閤金主要由 MoSi2構成,含有少量 Mo(SiAl)2和 Mo5Si3;(Mo0.94Nb0.06)(Si0.97Al0.03)2中開始齣現 NbSi2相,(Mo0.91Nb0.09)(Si0.97Al0.03)2和(Mo0.88Nb0.12)(Si0.97Al0.03)2閤金中Mo5Si3的衍射峰彊度進一步降低,而NbSi2的衍射峰略有增彊,因而添加Nb有利于形成C40結構的NbSi2,同時抑製Mo5Si3的產生。SEM觀察錶明閤金為多孔結構。
이Mo、Nb、Si、Al원소분말위원료,채용연소합성법제비명의성분분별위(Mo0.97Nb0.03)(Si0.97Al0.03)2、(Mo0.94Nb0.06)(Si0.97Al0.03)2、(Mo0.91Nb0.09)(Si0.97Al0.03)2여(Mo0.88Nb0.12)(Si0.97Al0.03)2등4충불동화함량적합금,연구기연소합성행위,분석연소합성과정중분말압배적연소모식、연소온도、연소파전연만연속솔이급산물조성。결과표명:수 Nb 함량증가,연소합성반응모식유라선연소축점전변위은태연소。첨가 Nb、Al 후,합금적최고연소온도승고,병수Nb함량증가정현선승고후강저적변화추세,기중(Mo0.91Nb0.09)(Si0.97Al0.03)2적연소온도최고,체도1924 K,단연소파만연속솔수Nb함량증가이축점강저。XRD결과표명:(Mo0.97Nb0.03)(Si0.97Al0.03)2합금주요유 MoSi2구성,함유소량 Mo(SiAl)2화 Mo5Si3;(Mo0.94Nb0.06)(Si0.97Al0.03)2중개시출현 NbSi2상,(Mo0.91Nb0.09)(Si0.97Al0.03)2화(Mo0.88Nb0.12)(Si0.97Al0.03)2합금중Mo5Si3적연사봉강도진일보강저,이NbSi2적연사봉략유증강,인이첨가Nb유리우형성C40결구적NbSi2,동시억제Mo5Si3적산생。SEM관찰표명합금위다공결구。
The alloys with the nominal composition of (Mo0.97Nb0.03) (Si0.97Al0.03)2, (Mo0.94Nb0.06) (Si0.97Al0.03)2, (Mo0.91-Nb0.09) (Si0.97Al0.03)2 and (Mo0.88Nb0.12) (Si0.97Al0.03)2 were prepared by combustion synthesis method,and Mo, Nb, Si, Al powders were used as the starting materials. The combustion mode, combustion temperature, velocity of the flame-front propagation and combustion products were investigated. The results indicate that the combustion mode depends on the content of Nb. With the increase of the content of Nb, the combustion mode gradually transits from a spinning combustion to a stable combustion. The combustion temperature of pure MoSi2 is the lowest in all the alloys. With the increase of the content of Nb, the combustion temperature grows up first and then drops down. The specimen of the nominal composition (Mo0.91Nb0.09) (Si0.97Al0.03)2 has the highest combustion temperature of 1 924 k. However, the velocity of the flame-front propagation is inversely proportional to the content of Nb. The X-Ray diffraction patterns show that the combustion products of (Mo0.97Nb0.03) (Si0.97Al0.03)2 specimen are mainly MoSi2, and a small amount of Mo (SiAl)2 and Mo5Si3 are also detected. The NbSi2 phase appears in (Mo0.94Nb0.06) (Si0.97Al0.03)2 specimen. The intensity of the Mo5Si3 peak decreased obviously in (Mo0.91Nb0.09) (Si0.97Al0.03)2 and (Mo0.88Nb0.12) (Si0.97Al0.03)2 specimens, so it is reasonable to speculate that the addition of Nb promotes the formation of NbSi2 and suppresses the formation of Mo5Si3. The SEM photographs show that the combustion products are porous structure materials.