摘要：针对机械合金化法制备Mg基复合纳米粉体耗时长、能耗大的不足,在H₂﹢SiH₄﹢Ar的混合气氛下,用直流电弧等离子体蒸发纯Mg制备了Mg基复合纳米粉体,粉体的生产率为0.39～0.43kg·h^-1。用XRD、TEM、DSC-TG、氧含量分析等手段对样品进行了分析。结果表明,样品中Mg相含量随气氛中H₂含量的增加而增加,Mg₂Si相、Si相含量减少,当H₂含量大于30%时,Si相在XRD谱上消失。样品平均粒度和氧含量随Mg相含量增加而增大。在室温大气条件下,样品中Mg₂Si相的含量越高则抗氧化性越好。在升温速度10℃/min,流动空气30mL/min的条件下,加热温度超过400℃后,复合粉体氧化速率急剧加快,至580℃左右几乎完全氧化。

关键词： 直流电弧；Mg基复合纳米粉体；钝化工艺；氧化特性

Abstract :The defect of Mg matrix composite nano-particles prepared by mechanical alloy is wasting time and power. The Mg matrix composite nano-particles were prepared by DC arc plasma in H₂﹢SiH₄+ Ar .The production rate of nano-particles was 0.39～0.43 kg/h. The structure and morphology as well as resistance oxidation of the nano-particles were analyzed using XRD, TEM, gas analysis, differential thermal and thermogravimetry analysis. The resultsshow that the mass fraction of Mg increase, Mg₂Si and Si decrease with content of H₂ increasing, and the nano-particles hardly contain Si over 30% content of H₂. The average sizes and mass fraction of oxygen increase with mass fraction of Mg increasing. The resistance oxidation of nano-particles enhance with mass fraction of Mg₂Si increasing at room temperature. The velocity of oxidation of nano-particles are evidently accelerated over 400 ℃ and completely are oxidized until 580℃in flow air. 

Keywords: DC arc plasma; Mg matrix composite nano-particles; stabilization technology; resistance oxidation