| 摘要: |
| 运用传热学理论对等离子弧粉末堆焊过程中粉末颗粒与转移型等离子弧之间的传热过程进行了分析计算,发现等离子弧粉末堆焊时,当堆焊粉末颗粒被送入等离子弧后粉末颗粒受等离子弧加热的速度主要取决于等离子弧的温度、热传导势及粉末颗粒的密度、尺寸和热物理性能等。对于100~200A的氩等离子弧,无论是熔点较低的铁基粉末颗粒还是熔点较高的碳化硼颗粒,被加热到熔化温度所需要的时间都在毫秒级水平(几毫秒至几十毫秒)。只是铁基粉末颗粒在等离子弧中的升温速度要比碳化硼颗粒快约1倍以上。 |
| 关键词: 等离子弧 粉末堆焊 粉末颗粒 传热 |
| DOI： |
| 分类号: |
| 基金项目:天津市自然科学基金资助项目(F200008) |
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| Evaluation of Powder's Thermal Behavior in Plasma Transferred-Arc Space (Ⅰ)——Study on Heat Transfer Between Powder Particle and Plasma |
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WANG Xi bao,JIA Feng-suo,WANG Xiao-feng
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The Centre of Surface Engineering Research, The College of Materials Science and Technology, Tianjin University, Tianjin 300072, China
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| Abstract: |
| The heat transfer between powder particles and the argon plasma transferred arc (PTA) fluid was theoretically analyzed and measured in this article based on heat conduction theories.It was found that the elevating velocity of particle's temperature in PTA plasma fluid mostly depend upon the plasma fluid's thermodynamics,particle's thermodynamics,mass density and particle's sizes.In the central plasma fluid with 100~200 A surfacing currents,not only the Fe base particles with a relatively lower melting point but also the boron carbide(B4C) particles with a relatively much higher melting point might be fully fused within milliseconds.However,the temperature elevation of Fe base particles is about one time faster than that's of boron carbide (B4C) particles |
| Key words: powder Fe base alloy B4C plasma transferred arc heat transfer |
