X.L. Jiang
金属学报(英文版)
Experimental results are reported on the primary carburization reaction between the tungsten powder and methane in the induction plasma, and the secondary carburization of the deposit on substrate at high temperature. Optical microscopy and scanning electron microscopy were used to examine the microstructures of starting tungsten powder, carburized powder, and deposit. X-ray diffraction analysis, thermal gravimetric analysis and microhardness measurement were used to characterize the structures and properties of the powder and the deposit. It is found that the primary carburization reaction in the induction plasma starts from the surface of tungsten particles when the particles are melted. Tungsten particles are partially carburized inside the reactive plasma. Complete carburization is achieved through the secondary carburization reaction of the deposit on substrate at high temperature.
关键词:
tungsten powder
,
null
,
null
,
null
邹敏明
,
田开文
,
黄伟
,
刘勇
,
史洪刚
,
易更
兵器材料科学与工程
利用感应等离子制备纳米Cu-30%Ag合金粉，研究了等离子气氛中氢气含量对纳米粉形貌、粒径的影响。结果表明，随着等离子气氛中氢气含量的逐渐升高，纳米粉粒径从213 nm减小至151 nm和117 nm，但纳米粉的形貌无明显变化。分析认为纳米粉粒径的变化归功于氢气的引入导致原料粉与等离子能量耦合程度的变化。
关键词:
氢气
,
铜银合金
,
粒径
,
感应等离子
刘晓平
,
王快社
,
胡平
,
陈强
稀有金属
利用感应等离子体技术制备出高纯致密球形钼粉,实现了钼粉的球化、致密化、细化和纯化,同时研究了感应等离子体功率和原料粉粒度对球化率的影响.采用扫描电子显微镜、X射线衍射仪和激光粒度分析仪对球化处理前后粉末的形貌、物相和粒度分布进行测试和分析.结果表明,形状不规则的原料钼粉,经等离子体球化处理后得到球形度好、表面光滑、分散性良好、球化率几乎可达100％的球形钼粉.球化处理后,钼粉粒度变细,且粒度分布更集中.相同工艺条件下,随着等离子体功率的增加,钼粉的球化率先增大后降低,当等离子体功率为25 kW时钼粉球化效果最好,粒度较小的钼粉球化率较高.随着钼粉球化率的提高,粉末的流动性得到显著改善,松装密度也得到提高.钼粉末的流动性由40 s/50 g提高为11 s/50 g,松装密度由2.3 g/cm3提高到6.1 g/cm3.
关键词:
感应等离子体
,
钼粉
,
球化
,
致密化
