等离子体法制备纳米Ni粉中热泳问题及其影响  

Thermo-Natatorial Phenomena and Influence in Preparing Nano Ni Powder by Plasma Arc Spraying Method

作　　者：蒋渝[1] 衡俊华[2] 刘明[1] 杨彦明[1] 陈家钊[1] 涂铭旌[1] 

机构地区：[1]四川大学,四川成都610065 [2]国家金属制品质量监督检验中心,河南郑州450007

出　　处：《稀有金属材料与工程》2005年第12期1901-1904,共4页Rare Metal Materials and Engineering

基　　金：四川大学青年科学基金(0030105505013)

摘　　要：利用等离子体法制备金属纳米镍粉。发现收集系统效率偏低,且平均粒度越小的粉末收得率越低。分析表明,对于纳米粒子不等温流场中的气固两相流输运过程,粒子沉降由重力沉降过渡到热泳沉降；粒子平均粒度从10μm下降到50nm时,热泳力与重力、马格纽斯升力的比值分别从0．07和0．02上升到2820和945,即热泳力因素占主导地位：温度梯度越大,粒子平均粒度越小,则热泳影响越显著,这是影响收得率的决定性因素。Nano-metal nickel powder was prepared by plasma arc spraying method. It is found that the efficiency of collection system is lower than designed target. The finer powder particle is, the lower collection rate is. As far as transportation process for the multi-phases flow between gas and nano solid particle, the sedimentation pattern varies from gravitation pattern to thermo-natatorial one. When particle size varies from 10μm to 50 nm, the ratio between thermo-natatorial force and gravity force incline from 0.07 to 2820 and the ratio between thermo-natatorial force and Magnus force incline from 0.02 to 945. With the incline of temperature gradient and the decline of particle size, the thermo-natatorial influence is more remarkable.

关 键 词：气固两相流 纳米Ni粉 制备 热泳 

分 类 号：TB383.1[一般工业技术—材料科学与工程]