欢迎您！东篱公司
退出
-
申报数据库
-
立项数据库
-
成果数据库
-
项目获奖数据库
中文摘要：
对Al-Bi偏晶点成分合金（Al-3．4％Bi，质量分数）开展了逆重力方向的定向凝固实验，考察了凝固速度对合金凝固组织的影响，分析了试样凝固组织形成过程．结果表明：Al-Bi偏晶点成分合金定向凝固时在固．液界面前沿液相内形成溶质Bi富集层，并发生液．液相变，少量相液滴在Marangoni迁移、Stokes沉积和试样自身下拉运动共同作用下进行空间迁移，当凝固速度较快时，凝固界面前沿所有尺寸的少量相液滴均向凝固界面迁移，合金凝固后少量相粒子尺寸呈现单峰分布；当试样凝固速度较慢时，部分少量相液滴在长大过程中其合速度方向按：指向凝固界面一背离凝固界面一再指向凝固界面顺序随液滴尺寸变化，合金凝固后少量相粒子尺寸分布呈现2个峰；当凝固速度较快时，少量相粒子平均尺寸〈R〉随凝固速度K近似呈〈R〉∝V0-1/2指数关系变化，随着凝固速度的下降，〈R〉与K间的关系向〈R〉∝V0-1/3指数关系趋近．
英文摘要：
Monotectic systems are a kind of extensive alloys. Many of them have great potentials for practical industry application. A lot of work has been carried out to study the solidification of monotectic alloys. But most of them focused on the microstructure formation during cooling a hyper-monotectic alloy through the miscibility gap in the liquid. Little work was done on the solidification behaviors of an alloy of monotectic composition. Directional solidification experiments were carried out with A1-Bi alloy of the monotectic composition （A1-3.4%Bi, mass fraction）. The influences of the solidification velocity on the microstructure were investigated. The microstructure evolution during solidification was analyzed. The results indicate that a solute-rich layer forms in front of the solidification interface and the liquid-liquid decomposition occurs there. When the alloy is solidified at such a high velocity so that the minority phase droplets of all sizes in front of the solidification interface are migrating to the solidification interface, the size distribution of the minority phase particles shows only one peak. When the alloy is solidified at a relatively low velocity, the minority phase droplets within a certain size range may move away from the solidification interface under the concurrent actions of the Marangoni migration, Stokes motion of the droplets as well as the movement of the sample. A1-3.4%Bi alloy solidified under such conditions shows a size distribution of the minority phase particles with two peaks. The average radius of the minority phase particles 〈R〉 depends on the solidification velocity V0 exponentially according to 〈R 〉∝V0-1/2 With the decrease of the solidification velocity, the dependence of the average radius of the minority phase particles varies towards to 〈 R 〉∝V0-1/3.
同期刊论文项目
同项目期刊论文
Effect of solute atoms on glass-forming ability for Fe-Y-B alloy: An ab initio molecular dynamics st
Experimental Investigation of Phase Equilibria in the Co-Cr-Nb System at 1000, 1100, and 1200 A degr
Microstructure and martensitic transformation behavior of Ni-Mn-Fe-Ga-B high-temperature shape memor
Temperature-dependent mechanical properties of alpha-/beta-Nb5Si3 phases from first-principles calcu
Formation mechanisms of self-organized core/shell and core/shell/corona microstructures in liquid dr
Thermodynamic, structural and elastic properties of Co3X (X=Ti, Ta, W, V, Al) compounds from first-p
Phase equilibria and composition dependence of martensitic transformation in Ni–Mn–Ga ternary system
Simultaneous improvement of ductility and shape memory effect of two-phase Ni53Mn22Co6Ga19 high-temp
Experimental Investigation and Thermodynamic Calculation of the Phase Equilibria in the Bi-Cu-Zn Ter
Experimental investigation and thermodynamic calculation of the phase equilibria in the Fe-Nb-Ti ter
Development of thermodynamic and kinetic databases in micro-soldering alloy systems and their applic
Experimental Investigation and Thermodynamic Calculation of the Phase Equilibria in the Al-Bi-Sn Ter
Mechanical and functional properties of two-phase Ni53Mn22Co6Ga19 high-temperature shape memory allo
Experimental Investigation and Thermodynamic Calculation of the Phase Equilibria in the Cr-Hf-Ti Ter
A bridge from monotectic alloys to liquid-phase-separated bulk metallic glasses: Design, microstruct
First-principles investigation of electronic, mechanical and thermodynamic properties of L1(2) order
Martensite stabilization and thermal cycling stability of two-phase NiMnGa-based high-temperature sh
Formation Mechanisms of Self-Organized Core/Shell and Core/Shell/Corona Microstructure in Liquid dro
期刊信息
位置：