| 摘要: |
| 为了解决微米铝粉燃烧动力学慢、点火延迟长、燃烧不充分等问题,以羰基铁为前驱体,用流化床化学气相沉积(FB-CVD)法对两种不同粒径的微米铝粉进行了包覆,利用SEM,XRD和TG-DSC对所制得的Fe/Al复合粉体进行了表征。结果表明铁层均匀致密地包覆在铝颗粒表面,由Q1铝粉所制备的样品中铁的含量分别为3.62%,7.82%,12.83%。铁的包覆对铝的放热性能有很大影响,复合粉体的高温放热峰温度相对于原始铝粉虽有所升高,但是其放热过程更迅速、更集中,氧化得更充分,1500℃时其增重由原始铝粉的20.74%提高到75.74%以上,铁的包覆量为7.82%的复合粉体增重可达到80.71%,其放热性能最优。 |
| 关键词: 铁铝复合粉体 化学气相沉积 核壳结构 放热反应 |
| DOI： |
| 分类号: |
| 基金项目:国家“八六三”项目(2009AA03Z317)。 |
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| Preparation and Thermal Characterization of Core-Shell Structure Fe/Al Composites Powders |
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CHEN Zhi-an1,2, HU Mu-lin2, TANG Shao-yan1, WANG Zhen-ye2
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(1. Hunan University of Technology, Zhuzhou 421000, China;2. State Key Laboratory of Materials Processing and Die and Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China)
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| Abstract: |
| In order to solve the micro aluminum combustion problems of reaction kinetics, long ignition delays and incomplete combustion,Core-shell Fe/Al composites were successfully prepared by fluidized bed chemical vapor deposition(FB-CVD)with two kinds of micro aluminum and iron carbonyl as precursor. The characterization of the as-prepared composites was carried out using SEM, XRD and simultaneous TG-DSC. It is found that the aluminum core is coated compactly and uniformly by an iron layer ,the iron contents of the samples prepared by Q1are 3.62%,7.82%,12.83%,respectively. Exothermic reaction of the obtained composite powders shows significant improvement compared to pure aluminum powders. Although the exothermic peak temperature of the composite powders is higher than that of pure micrometer-sized aluminum powders, heat release is obviously improved.The mass gain increases from 20.74% of pure Q1to over 75.74% of Q1coated up to 1500℃.Composite powder contained 7.82% of iron has the maximum mass gain of 80.71% and an optimal thermal performance is obtained. |
| Key words: Fe/Al composites Chemical vapor deposition Core-shell structure Exothermic reaction |
