本文主要研究内容
作者李振阳(2019)在《球磨工艺和不同类型添加剂对La5Mg95-xNix(x= 5、10、15)合金组织和储氢性能的影响》一文中研究指出:镁基合金由于原料丰富、成本低和储氢容量大等优点成为最有开发前景的储氢材料之一。但是,这类材料吸放氢动力学性能较差,大大影响了其储氢性能和应用。为探索改进镁基储氢材料性能的途径,本文选取La5Mg95-xNix(x=5、10、15)合金为研究对象,用真空感应熔炼法制备了该合金,对合金铸态组织和储氢性能进行详细研究,在此基础上研究球磨纳米化和不同类型添加剂对La5Mg85Ni10合金组织和储氢性能的影响规律,另外还从热力学和动力学方面对储氢性能的改善机理进行研究。主要结果如下:La5Mg95-xNix(x=5、10、15)铸态合金中 La2Mg17为主相,Mg2Ni、La2Ni3、Mg为第二相,=5合金中还有LaMg2相。随Ni含量增加和Mg含量降低,Mg2Ni含量增加。氢化后合金由MgH2、Mg2NiH4和稀土氢化物LaH3组成,脱氢后合金均由Mg2Ni、Mg和稀土氢化物LaH3组成。由此推断吸氢和脱氢过程发生的反应分别为Mg+H2(?)MgH2和Mg2Ni+H2(?)Mg2NiH4。Ni含量增加显著提高了合金储氢动力学性能,但降低了合金吸放氢速率。其中x= 15合金的放氢活化能值最低,为57.7 kJ/mol,对应的吸放氢速率最高。此外,随Ni含量增加材料的热力学性能先提高后降低,其中,La5Mg85Ni10合金表现出最好的热力学性质,ΔH=-82.1 kJ/mol,ΔS=-132.0 J/mol/K。随球磨时间增加La2Mg17相的衍射峰逐渐变宽,Mg2Ni相衍射峰保持不变,放氢活化能(Ea)先减小后增大。随球磨时间增加ΔH和ΔS先减少后增加。球磨10 h的La5Mg85Ni10合金表现出最好的热力学和动力学性能,Ea最低为49.6 kJ/mol,360 ℃下5 min 内吸收5.4 wt.%H2,3 min 内放出5.2 wt.%H2,ΔH和AS最低分别为-72.1 kJ/mol和-123.2 J/mol/K。由此可见,纳米结构对改善储氢材料的储氢动力学和热力学具有积极作用。研究了过渡金属化合物催化剂的种类和添加量对球磨时间10 h La5Mg85Ni10合金组织和储氢性能的影响。把1、3、5、7 wt.%的TiF3纳米颗粒和铸态La5Mg85Ni10合金进行混合球磨 10h,制备了 La5Mg85Ni10+x wt.%TiF3(x= 1、3、5、7)催化合金。结果表明催化合金吸氢后生成MgF2和TiH2,合金储氢容量有所降低,Ea先降低后升高,添加5 wt.%TiF3时放氢活化能最低Ea=45.2 kJ/mol。另一方面,La5Mg85Ni10合金分别添加5 wt.%TiF3、Cr203和NbF5添加剂后再各自球磨10 h,对比发现TiF3较Cr203和NbF5具有更好的催化效果,这是因为TiF3纳米颗粒能细化晶粒提供氢扩散通道,降低合金形核驱动力和促进脱氢反应。
Abstract
mei ji ge jin you yu yuan liao feng fu 、cheng ben di he chu qing rong liang da deng you dian cheng wei zui you kai fa qian jing de chu qing cai liao zhi yi 。dan shi ,zhe lei cai liao xi fang qing dong li xue xing neng jiao cha ,da da ying xiang le ji chu qing xing neng he ying yong 。wei tan suo gai jin mei ji chu qing cai liao xing neng de tu jing ,ben wen shua qu La5Mg95-xNix(x=5、10、15)ge jin wei yan jiu dui xiang ,yong zhen kong gan ying rong lian fa zhi bei le gai ge jin ,dui ge jin zhu tai zu zhi he chu qing xing neng jin hang xiang xi yan jiu ,zai ci ji chu shang yan jiu qiu mo na mi hua he bu tong lei xing tian jia ji dui La5Mg85Ni10ge jin zu zhi he chu qing xing neng de ying xiang gui lv ,ling wai hai cong re li xue he dong li xue fang mian dui chu qing xing neng de gai shan ji li jin hang yan jiu 。zhu yao jie guo ru xia :La5Mg95-xNix(x=5、10、15)zhu tai ge jin zhong La2Mg17wei zhu xiang ,Mg2Ni、La2Ni3、Mgwei di er xiang ,=5ge jin zhong hai you LaMg2xiang 。sui Nihan liang zeng jia he Mghan liang jiang di ,Mg2Nihan liang zeng jia 。qing hua hou ge jin you MgH2、Mg2NiH4he xi tu qing hua wu LaH3zu cheng ,tuo qing hou ge jin jun you Mg2Ni、Mghe xi tu qing hua wu LaH3zu cheng 。you ci tui duan xi qing he tuo qing guo cheng fa sheng de fan ying fen bie wei Mg+H2(?)MgH2he Mg2Ni+H2(?)Mg2NiH4。Nihan liang zeng jia xian zhe di gao le ge jin chu qing dong li xue xing neng ,dan jiang di le ge jin xi fang qing su lv 。ji zhong x= 15ge jin de fang qing huo hua neng zhi zui di ,wei 57.7 kJ/mol,dui ying de xi fang qing su lv zui gao 。ci wai ,sui Nihan liang zeng jia cai liao de re li xue xing neng xian di gao hou jiang di ,ji zhong ,La5Mg85Ni10ge jin biao xian chu zui hao de re li xue xing zhi ,ΔH=-82.1 kJ/mol,ΔS=-132.0 J/mol/K。sui qiu mo shi jian zeng jia La2Mg17xiang de yan she feng zhu jian bian kuan ,Mg2Nixiang yan she feng bao chi bu bian ,fang qing huo hua neng (Ea)xian jian xiao hou zeng da 。sui qiu mo shi jian zeng jia ΔHhe ΔSxian jian shao hou zeng jia 。qiu mo 10 hde La5Mg85Ni10ge jin biao xian chu zui hao de re li xue he dong li xue xing neng ,Eazui di wei 49.6 kJ/mol,360 ℃xia 5 min nei xi shou 5.4 wt.%H2,3 min nei fang chu 5.2 wt.%H2,ΔHhe ASzui di fen bie wei -72.1 kJ/molhe -123.2 J/mol/K。you ci ke jian ,na mi jie gou dui gai shan chu qing cai liao de chu qing dong li xue he re li xue ju you ji ji zuo yong 。yan jiu le guo du jin shu hua ge wu cui hua ji de chong lei he tian jia liang dui qiu mo shi jian 10 h La5Mg85Ni10ge jin zu zhi he chu qing xing neng de ying xiang 。ba 1、3、5、7 wt.%de TiF3na mi ke li he zhu tai La5Mg85Ni10ge jin jin hang hun ge qiu mo 10h,zhi bei le La5Mg85Ni10+x wt.%TiF3(x= 1、3、5、7)cui hua ge jin 。jie guo biao ming cui hua ge jin xi qing hou sheng cheng MgF2he TiH2,ge jin chu qing rong liang you suo jiang di ,Eaxian jiang di hou sheng gao ,tian jia 5 wt.%TiF3shi fang qing huo hua neng zui di Ea=45.2 kJ/mol。ling yi fang mian ,La5Mg85Ni10ge jin fen bie tian jia 5 wt.%TiF3、Cr203he NbF5tian jia ji hou zai ge zi qiu mo 10 h,dui bi fa xian TiF3jiao Cr203he NbF5ju you geng hao de cui hua xiao guo ,zhe shi yin wei TiF3na mi ke li neng xi hua jing li di gong qing kuo san tong dao ,jiang di ge jin xing he qu dong li he cu jin tuo qing fan ying 。
论文参考文献
论文详细介绍
论文作者分别是来自山东大学的李振阳,发表于刊物山东大学2019-07-16论文,是一篇关于镁基储氢合金论文,合金化论文,球磨论文,催化论文,动力学论文,热力学论文,山东大学2019-07-16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,资料来自山东大学2019-07-16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。
标签:镁基储氢合金论文; 合金化论文; 球磨论文; 催化论文; 动力学论文; 热力学论文; 山东大学2019-07-16论文;