(吉林工業(yè)大學 材料科學與工程學院, 長春 130025)
摘 要: 采用連續(xù)性理論結合外加顆粒在離心力場中運動規(guī)律基于柱坐標系建立了離心力場中外加顆粒分布的數(shù)學模型。采用該數(shù)學模型,以離心鑄造法制備SiCp/Al基梯度功能材料為例,分析了顆粒沉積過程,研究了離心加速度G、顆粒初始體積分數(shù)、澆注溫度、顆粒與合金密度差等對顆粒分布的影響 模擬結果與實驗均表明,提高離心加速度G和澆注溫度,降低顆粒初始體積分數(shù),可使梯度分布變化加劇,外側顆粒濃度增大(顆粒密度大于合金密度時), 而利用顆粒與合金的密度差異,可以獲得顆粒富集于內(nèi)、外側的梯度材料。將實驗數(shù)據(jù)與模擬值進行了比較,兩者吻合程度較好。
關鍵字: 離心力場; 外加顆粒; SiCp;體積分數(shù); 梯度功能材料
(College of Materials Science and Engineering, Jilin University of Technology,Changchun 130025, P.R.China)
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 SiCpgradient 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 ρs> ρl). 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.
Key words: centrifugal force field; added particle; SiCp ; volume fraction; functional gradient material


