工艺因素对SiC_p/AZ91复合材料颗粒均匀性的影响  

Effects of Processing Parameters on Uniform Distribution of SiC_p Particulate in SiC_p/AZ91 Magnesium Matrix Composites

作　　者：南宏强[1] 袁森[1] 王武孝[1] 张菊梅[2] 王志虎[1] 罗红斌[1] 

机构地区：[1]西安理工大学材料科学与工程学院 [2]西安科技大学材料科学与工程学院

出　　处：《特种铸造及有色合金》2007年第4期302-305,共4页Special Casting & Nonferrous Alloys

摘　　要：用半固态搅拌法成功制备出了颗粒分布均匀、孔隙率低的SiCp/AZ91颗粒增强镁基复合材料,研究了搅拌速度、颗粒尺寸、搅拌叶轮旋向、颗粒预处理工艺等因素对SiCp/AZ91复合材料中颗粒分布均匀性的影响。研究发现,颗粒预处理对分布均匀性有显著影响,经过高温预氧化处理的SiC颗粒与镁合金基体润湿性很好,在半固态搅拌制备中能有效改善颗粒与基体的界面结合和颗粒分布均匀性。在其他工艺因素一定时,颗粒粒径越大,分布越均匀;搅拌速度越低,颗粒分布越不均匀。当颗粒较小时(<50μm),搅拌叶轮的旋向对分布均匀性有重要影响。确定优选工艺参数为:上旋桨、半固态等温温度为585℃、搅拌速度为400r/min、颗粒尺寸为50μm、颗粒的体积分数为15%。SiCp particulate reinforced magnesium matrix composites SiCp/AZ91 with low porosity and uniformly distributed particles were successfully prepared by semi-solid stirring. The effects of processing parameters, such as stirring velocity, particle size, rotation direction of propeller stirrer, particle pretreatment, on uniform distribution of the particles in the composites have been investigated. The results show that pretreatment has the dominant effect on the uniform distribution of the particles. High temperature pre-oxidized treated SiC particle can effectively improve interface bonding between particle and the magnesium alloy matrix and promote the uniform distribution due to its better wettability with the matrix alloy. With given other parameters, the larger the particle diameters are, the more uniform distribution the particle is; the lower the stirring speed is, the more uneven distribution the particle is. In addition, with the size of the particle less than 50 μm, the rotation direction of the impeller stirrer is a significant parameter for uniform distribution of the particles. The optimized processing parameters are determined as follows: ascending propeller stirrer, holding temperature of 580 ℃, stirring speed at 400 r/min, particle size of 50 μm and volume fraction of particle in the matrix of 15%.

关 键 词：半固态机械搅拌 镁基复合材料 工艺因素 颗粒分布均匀性 

分 类 号：TB331[一般工业技术—材料科学与工程]