离心力场中外加颗粒分布模型

来源期刊：中国有色金属学报2000年第6期

论文作者：张新平 于思荣 何镇明

文章页码：832 - 836

关键词：离心力场； 外加颗粒； SiC_p；体积分数； 梯度功能材料

Key words：centrifugal force field； added particle； SiC_p ； volume fraction; functional gradient material

摘    要：采用连续性理论结合外加颗粒在离心力场中运动规律基于柱坐标系建立了离心力场中外加颗粒分布的数学模型。采用该数学模型，以离心铸造法制备SiC_p/Al基梯度功能材料为例，分析了颗粒沉积过程，研究了离心加速度G、颗粒初始体积分数、浇注温度、颗粒与合金密度差等对颗粒分布的影响 模拟结果与实验均表明，提高离心加速度G和浇注温度，降低颗粒初始体积分数，可使梯度分布变化加剧，外侧颗粒浓度增大(颗粒密度大于合金密度时)， 而利用颗粒与合金的密度差异，可以获得颗粒富集于内、外侧的梯度材料。将实验数据与模拟值进行了比较，两者吻合程度较好。

Abstract: The numerical modeling of the particle distribution in the centrifugal force field was established by using continuity theory and the moving law of particle.The particle distribution process in the centrifugal force field was analyzed theoretically byusing the established model. The influences of centrifugal acceleration G, primary volume fraction, pour temperature and the density difference between theparticle andthe base alloy on SiC_pgradient distribution were studied. With the increases in centrifugal acceleration G and pour temperature, and the decrease of the primary volume fraction， the particle gradient distribution changes more greatly and the content of particle in the outer shell becomes larger( when ρ_s> ρ_l). In the centrifugal force field， segregation of particles occurs due to the centrifugal force， either to the outer or to the inner part of the casting， depending on the relative densities of particles and the base alloy. The theoryand experiment results were in good agreement.