摘要
为了分析铝合金燃烧过程中存在的不同金属相间对氧气的竞争反应特性,采用热重-差示扫描量热(TG-DSC)对镁铝二元合金的氧化性能进行分析;采用X射线衍射仪(XRD)对反应前后样品的相组成进行检测;采用扫描电子显微镜(SEM)对反应物及产物的形貌进行观测;采用自制的燃烧反应装置对镁铝合金粉在空气中的燃烧过程进行了研究。结果表明,Mg-Al合金在空气中反应时,镁与氧气的反应优先于铝与氧气的反应;在10℃/min的升温速率下,镁与氧气的优先反应不能阻碍Al的氧化,二者的氧化产物会继续反应生成MgAl_(2)O_(4),该反应在温度高于800℃时变得更加明显;当镁铝合金发生燃烧时能观测到粒子的微爆现象,Mg与氧气的优先反应使得铝与N_(2)反应生成AlN;释能途径不同,使得铝的燃烧放热出现巨大的差别,当铝转化为AlN,其反应放热大大减少(约为12 kJ/g),只有其被氧化成Al_(2)O_(3)时放出热量的40%。
In order to analyze the competitive reaction of different metal phases in the combustion process of aluminum alloy,thermogravimetric differential scanning calorimetry(TG-DSC)was used to analyze the oxidation performance of Mg-Al binary alloy,and an X-ray diffractometer(XRD)was used to analyze the phase composition of the samples before and after reaction,and scanning electron microscope(SEM)was used to observe the morphology of the samples,and self-made combustion system was used to study the combustion process of Mg-Al alloy powder in the air.The results show that Mg in the alloy is oxidized faster than Al when the alloy powder is heated slowly with a rate of 10℃/min in air,and the preferential reaction of Mg couldn′t block the oxidation of Al,and their products further react to form MgAl_(2)O_(4).The formation of MgAl_(2)O_(4) becomes more obvious when the temperature is higher than 800℃.When Mg-Al alloy is burned in air,the micro-explosion phenomenon can be observed,and only nitrogen can reach the reaction zone of liquid Al due to the preferential combustion of Mg with oxygen,and it leads to that the Al in the alloy matrix only reacts with nitrogen to form AlN.Therefore,the different reaction processes indicate that the reaction heat of Al has a great difference.When Al is converted into AlN in the combustion process of Mg-Al alloy,the reaction heat decreases greatly(about 12 kJ/g),which is only 40%of the value when Al is oxidized to Al_(2)O_(3).
作者
谢晓
朱晨光
赵凤起
仪建华
秦钊
李海建
XIE Xiao;ZHU Chen-guang;ZHAO Feng-qi;YI Jian-hua;QIN Zhao;LI Hai-jian(Science and Technology on Combustion and Explosion Laboratory,Xi′an Modern Chemistry Research Institute,Xi′an 710065,China;School of Chemistry and Chemical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)
出处
《火炸药学报》
EI
CAS
CSCD
北大核心
2022年第2期222-228,I0004,共8页
Chinese Journal of Explosives & Propellants
基金
国家自然科学基金(No.21905224)。
关键词
物理化学
MG-AL合金
ALN
优先氧化
氮化反应机理
微爆反应
physical chemistry
Mg-Al alloy
AlN
preferential oxidation
nitridation mechanism
micro-explosion reaction