本文主要研究内容
作者赵铁军（2019）在《气相爆轰合成碳基磁性复合材料及其电磁波吸波性能研究》一文中研究指出：当今信息传递、工业装备、军事装备朝着智能化发展,正在建设的5G网络将进一步深化信息智能化对生产生活带来巨大的变革。军事装备的革新与复杂环境下电磁战为背景的现代化战争中,不仅需要具有隐身功能的设备,还需要空中电磁干扰域的掩护。针对空中电磁干扰域,常用烟幕弹爆炸或燃烧释放含有微/纳米颗粒的烟幕实施电磁干扰来影响雷达、红外等的侦查。爆轰法是一种动态制备纳米材料的方法,通过爆炸可在瞬间获得纳米材料并能在空中形成由纳米颗粒构成的动态烟幕区,制造短时电磁波干扰区域,对敌方的电子侦查实施干扰。作为空中动态吸波研究的一部分,本文旨在通过爆轰方式制备电磁波吸波材料,分析其对电磁波的吸收性能。在此基础上选择目标产物,为空中动态吸波研究提供吸波材料的选择方案。Fe@C纳米颗粒、Co@C纳米颗粒、CNTs具有优良的介电性能与磁性能,同时兼有良好的吸波能力,常用于吸波体的设计。本文采用气相爆轰法制备了Fe@C纳米颗粒、Co@C纳米颗粒、CNTs三种碳基磁性复合材料。研究了爆源种类和爆源中气体摩尔比对碳基磁性复合材料物相、形貌、磁性等的影响,并探究了它们在1～18 GHz频率范围内的电磁特性与吸波能力。可得到如下结论:研究了爆源种类及爆源中气体摩尔比对Fe@C纳米颗粒形貌、物相等的影响,并分析了其在1～18 GHz频率范围内的吸波性能。爆源种类对Fe@C纳米颗粒形貌的影响比较显著,爆源气体摩尔比对Fe@C纳米颗粒的形貌及物相影响比较明显。爆源零氧平衡时,获得的产物为Fe@C纳米颗粒,金属核为铁/碳化铁,碳壳为部分石墨化的无定型碳,高燃烧热的爆源制备的Fe@C颗粒尺寸较大。在氢-氧爆源正氧条件下,降低爆源中氢的占比,部分铁将被氧化成氧化亚铁或磁铁矿,同时粒径随之增大。甲烷-氧负氧反应时,随着甲烷摩尔比的提高,产物的形貌将由核-壳结构向核壳-碳纳米管结构转变。然而,苯-氧爆源在负氧平衡时,苯占比增高时,产物中出现“碳囊”结构,且碳壳厚度逐渐增大。不过,爆源种类及爆源气体摩尔比对石墨化程度影响甚微。初始Fe@C纳米颗粒的电磁波吸波性能较差,Ar气保护700 ℃热处理可明显提高其电磁波吸波能力。初始Fe@C纳米颗粒的反射损耗不足-2 dB;经Ar气保护热处理后,其吸波能力明显提升,RL值为-17.1 dB,对应的频率为5.4 GHz,样品厚度为3 mm,有效吸收频段为7.1 GHz(2.7～9.8 GHz)(样品厚度2～5 mm)。首次采用气相爆轰法制备了Co@C纳米颗粒,并探讨了其对电磁波的吸收问题。以乙酰丙酮钴(Ⅲ)为前驱体,分别以氢-氧、甲烷-氧、苯-氧为爆源,研究了爆源对产物形貌、物相及石墨化程度的影响。结果发现爆源对碳-钴复合材料的形貌影响很明显,爆源零氧平衡时,低燃烧热的氢-氧爆源制备的产物为Co@C-CNTs的复合材料;燃烧热较高的甲烷-氧、苯-氧爆源得到的产物为Co@C颗粒,且高燃烧热爆源得到的产物颗粒尺寸偏大。甲烷-氧爆源由零氧平衡向负氧平衡变化时,产物由Co@C纳米颗粒逐渐变为Co@C-CNTs共存的复合材料。初始Co@C纳米颗粒的最小RL值出现在11.88 GHz处,大小为-2.8 dB,对应的厚度为1mm;Ar气保护700℃热处理后,其最小RL值为-17.5 dB,出现在16.98 GHz,对应的样品厚度为5 mm。以氢-氧、甲烷-氧为爆源,二茂铁为前驱体,研究了气相爆轰制备CNTs的影响因素,并讨论了在1～18 GHz频率内其对电磁波的吸收情况。氢-氧爆源在负氧条件下,氢氧摩尔比对产物形貌形貌影响非常明显,随着氢占比的提高,产物由Fe@C纳米颗粒转向Fe@C-CNTs,且CNTs占比逐渐增大,Fe@C颗粒的尺寸大小逐渐均匀。甲烷-氧摩尔比1:1,二茂铁质量为2 g时,可得到长度几微米,外径30 nm,内径15 nm的多壁CNTs。结合爆轰过程的ZND模型与V-L-S生长模型提出了气相爆轰制备CNTs的生长机制。制备的CNTs的电磁波吸收能力较差,当厚度为2mm时出现最小RL值-6.1 dB,对应的频率为11.2 GHz;随着样品厚度的增大,反射损耗最小值向低频偏移。探究了初始碳基磁性复合材料吸波性能较差的原因,并指出核-壳结构的碳基磁性复合材料比较适用于空中动态吸波的研究。阻抗不匹配是初始样品电磁波吸收能力不高的主要原因。初始碳基磁性复合材料中存在大量的无定型碳且金属结晶度较低,导致其复介电常数均很大,进而阻抗匹配度不到0.4,电磁波在吸波体-空气界面发生反射,很难进入吸波体内部。经Ar气保护700 ℃热处理后,Fe@C、Co@C的物相、微观结构发生不同程度的变化,复介电常数明显减小,阻抗匹配度明显提高,电磁波很容易进入吸波体内部,并在介电损耗与磁损耗协同作用下实现对入射电磁波的有效吸收。在爆轰反应中,CNTs结构极易破碎,电磁波吸波性能无法保证;而核-壳结构的碳包金属颗粒更加稳定,且Ar气保护热处理后,Fe@C与Co@C纳米颗粒的电磁波吸波能力明显提高。因此,在空中动态电磁波吸波研究中,核-壳结构的碳基磁性复合材料是一种比较合适的备选材料。
Abstract
dang jin xin xi chuan di 、gong ye zhuang bei 、jun shi zhuang bei chao zhao zhi neng hua fa zhan ,zheng zai jian she de 5Gwang lao jiang jin yi bu shen hua xin xi zhi neng hua dui sheng chan sheng huo dai lai ju da de bian ge 。jun shi zhuang bei de ge xin yu fu za huan jing xia dian ci zhan wei bei jing de xian dai hua zhan zheng zhong ,bu jin xu yao ju you yin shen gong neng de she bei ,hai xu yao kong zhong dian ci gan rao yu de yan hu 。zhen dui kong zhong dian ci gan rao yu ,chang yong yan mu dan bao zha huo ran shao shi fang han you wei /na mi ke li de yan mu shi shi dian ci gan rao lai ying xiang lei da 、gong wai deng de zhen cha 。bao hong fa shi yi chong dong tai zhi bei na mi cai liao de fang fa ,tong guo bao zha ke zai shun jian huo de na mi cai liao bing neng zai kong zhong xing cheng you na mi ke li gou cheng de dong tai yan mu ou ,zhi zao duan shi dian ci bo gan rao ou yu ,dui di fang de dian zi zhen cha shi shi gan rao 。zuo wei kong zhong dong tai xi bo yan jiu de yi bu fen ,ben wen zhi zai tong guo bao hong fang shi zhi bei dian ci bo xi bo cai liao ,fen xi ji dui dian ci bo de xi shou xing neng 。zai ci ji chu shang shua ze mu biao chan wu ,wei kong zhong dong tai xi bo yan jiu di gong xi bo cai liao de shua ze fang an 。Fe@Cna mi ke li 、Co@Cna mi ke li 、CNTsju you you liang de jie dian xing neng yu ci xing neng ,tong shi jian you liang hao de xi bo neng li ,chang yong yu xi bo ti de she ji 。ben wen cai yong qi xiang bao hong fa zhi bei le Fe@Cna mi ke li 、Co@Cna mi ke li 、CNTssan chong tan ji ci xing fu ge cai liao 。yan jiu le bao yuan chong lei he bao yuan zhong qi ti ma er bi dui tan ji ci xing fu ge cai liao wu xiang 、xing mao 、ci xing deng de ying xiang ,bing tan jiu le ta men zai 1～18 GHzpin lv fan wei nei de dian ci te xing yu xi bo neng li 。ke de dao ru xia jie lun :yan jiu le bao yuan chong lei ji bao yuan zhong qi ti ma er bi dui Fe@Cna mi ke li xing mao 、wu xiang deng de ying xiang ,bing fen xi le ji zai 1～18 GHzpin lv fan wei nei de xi bo xing neng 。bao yuan chong lei dui Fe@Cna mi ke li xing mao de ying xiang bi jiao xian zhe ,bao yuan qi ti ma er bi dui Fe@Cna mi ke li de xing mao ji wu xiang ying xiang bi jiao ming xian 。bao yuan ling yang ping heng shi ,huo de de chan wu wei Fe@Cna mi ke li ,jin shu he wei tie /tan hua tie ,tan ke wei bu fen dan mo hua de mo ding xing tan ,gao ran shao re de bao yuan zhi bei de Fe@Cke li che cun jiao da 。zai qing -yang bao yuan zheng yang tiao jian xia ,jiang di bao yuan zhong qing de zhan bi ,bu fen tie jiang bei yang hua cheng yang hua ya tie huo ci tie kuang ,tong shi li jing sui zhi zeng da 。jia wan -yang fu yang fan ying shi ,sui zhao jia wan ma er bi de di gao ,chan wu de xing mao jiang you he -ke jie gou xiang he ke -tan na mi guan jie gou zhuai bian 。ran er ,ben -yang bao yuan zai fu yang ping heng shi ,ben zhan bi zeng gao shi ,chan wu zhong chu xian “tan nang ”jie gou ,ju tan ke hou du zhu jian zeng da 。bu guo ,bao yuan chong lei ji bao yuan qi ti ma er bi dui dan mo hua cheng du ying xiang shen wei 。chu shi Fe@Cna mi ke li de dian ci bo xi bo xing neng jiao cha ,Arqi bao hu 700 ℃re chu li ke ming xian di gao ji dian ci bo xi bo neng li 。chu shi Fe@Cna mi ke li de fan she sun hao bu zu -2 dB;jing Arqi bao hu re chu li hou ,ji xi bo neng li ming xian di sheng ,RLzhi wei -17.1 dB,dui ying de pin lv wei 5.4 GHz,yang pin hou du wei 3 mm,you xiao xi shou pin duan wei 7.1 GHz(2.7～9.8 GHz)(yang pin hou du 2～5 mm)。shou ci cai yong qi xiang bao hong fa zhi bei le Co@Cna mi ke li ,bing tan tao le ji dui dian ci bo de xi shou wen ti 。yi yi xian bing tong gu (Ⅲ)wei qian qu ti ,fen bie yi qing -yang 、jia wan -yang 、ben -yang wei bao yuan ,yan jiu le bao yuan dui chan wu xing mao 、wu xiang ji dan mo hua cheng du de ying xiang 。jie guo fa xian bao yuan dui tan -gu fu ge cai liao de xing mao ying xiang hen ming xian ,bao yuan ling yang ping heng shi ,di ran shao re de qing -yang bao yuan zhi bei de chan wu wei Co@C-CNTsde fu ge cai liao ;ran shao re jiao gao de jia wan -yang 、ben -yang bao yuan de dao de chan wu wei Co@Cke li ,ju gao ran shao re bao yuan de dao de chan wu ke li che cun pian da 。jia wan -yang bao yuan you ling yang ping heng xiang fu yang ping heng bian hua shi ,chan wu you Co@Cna mi ke li zhu jian bian wei Co@C-CNTsgong cun de fu ge cai liao 。chu shi Co@Cna mi ke li de zui xiao RLzhi chu xian zai 11.88 GHzchu ,da xiao wei -2.8 dB,dui ying de hou du wei 1mm;Arqi bao hu 700℃re chu li hou ,ji zui xiao RLzhi wei -17.5 dB,chu xian zai 16.98 GHz,dui ying de yang pin hou du wei 5 mm。yi qing -yang 、jia wan -yang wei bao yuan ,er mao tie wei qian qu ti ,yan jiu le qi xiang bao hong zhi bei CNTsde ying xiang yin su ,bing tao lun le zai 1～18 GHzpin lv nei ji dui dian ci bo de xi shou qing kuang 。qing -yang bao yuan zai fu yang tiao jian xia ,qing yang ma er bi dui chan wu xing mao xing mao ying xiang fei chang ming xian ,sui zhao qing zhan bi de di gao ,chan wu you Fe@Cna mi ke li zhuai xiang Fe@C-CNTs,ju CNTszhan bi zhu jian zeng da ,Fe@Cke li de che cun da xiao zhu jian jun yun 。jia wan -yang ma er bi 1:1,er mao tie zhi liang wei 2 gshi ,ke de dao chang du ji wei mi ,wai jing 30 nm,nei jing 15 nmde duo bi CNTs。jie ge bao hong guo cheng de ZNDmo xing yu V-L-Ssheng chang mo xing di chu le qi xiang bao hong zhi bei CNTsde sheng chang ji zhi 。zhi bei de CNTsde dian ci bo xi shou neng li jiao cha ,dang hou du wei 2mmshi chu xian zui xiao RLzhi -6.1 dB,dui ying de pin lv wei 11.2 GHz;sui zhao yang pin hou du de zeng da ,fan she sun hao zui xiao zhi xiang di pin pian yi 。tan jiu le chu shi tan ji ci xing fu ge cai liao xi bo xing neng jiao cha de yuan yin ,bing zhi chu he -ke jie gou de tan ji ci xing fu ge cai liao bi jiao kuo yong yu kong zhong dong tai xi bo de yan jiu 。zu kang bu pi pei shi chu shi yang pin dian ci bo xi shou neng li bu gao de zhu yao yuan yin 。chu shi tan ji ci xing fu ge cai liao zhong cun zai da liang de mo ding xing tan ju jin shu jie jing du jiao di ,dao zhi ji fu jie dian chang shu jun hen da ,jin er zu kang pi pei du bu dao 0.4,dian ci bo zai xi bo ti -kong qi jie mian fa sheng fan she ,hen nan jin ru xi bo ti nei bu 。jing Arqi bao hu 700 ℃re chu li hou ,Fe@C、Co@Cde wu xiang 、wei guan jie gou fa sheng bu tong cheng du de bian hua ,fu jie dian chang shu ming xian jian xiao ,zu kang pi pei du ming xian di gao ,dian ci bo hen rong yi jin ru xi bo ti nei bu ,bing zai jie dian sun hao yu ci sun hao xie tong zuo yong xia shi xian dui ru she dian ci bo de you xiao xi shou 。zai bao hong fan ying zhong ,CNTsjie gou ji yi po sui ,dian ci bo xi bo xing neng mo fa bao zheng ;er he -ke jie gou de tan bao jin shu ke li geng jia wen ding ,ju Arqi bao hu re chu li hou ,Fe@Cyu Co@Cna mi ke li de dian ci bo xi bo neng li ming xian di gao 。yin ci ,zai kong zhong dong tai dian ci bo xi bo yan jiu zhong ,he -ke jie gou de tan ji ci xing fu ge cai liao shi yi chong bi jiao ge kuo de bei shua cai liao 。
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论文作者分别是来自大连理工大学的赵铁军，发表于刊物大连理工大学2019-07-19论文，是一篇关于爆轰法论文,碳包铁论文,碳包钴论文,碳纳米管论文,吸波性能论文,大连理工大学2019-07-19论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自大连理工大学2019-07-19论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。