熔体发泡法制备镁基/SiC_(p)复合泡沫的工艺  

Preparation of Mg-based/SiC_(p) composite foam by melt foaming method

作　　者：黄闻战 徐建荣 罗洪杰 张丽 张健 Huang Wenzhan;Xu Jianrong;Luo Hongjie;Zhang Li;Zhang Jian(School of Material Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;School of Metallurgy,Northeastern University,Shenyang 110819,China)

机构地区：[1]太原科技大学材料科学与工程学院,太原030024 [2]东北大学冶金学院,沈阳110819

出　　处：《材料与冶金学报》2022年第3期178-183,共6页Journal of Materials and Metallurgy

基　　金：博士启动基金(20192066);来晋优秀博士基金(20202021);山西省高等学校科技创新(2020L0342).

摘　　要：以白云石(主要成分为MgCO_(3))为发泡剂、碳化硅颗粒(SiC_(p))为增黏剂,研究了镁基/SiC_(p)复合泡沫的熔体发泡制备工艺,分析了SiC_(p)与镁合金熔体的界面结合状态及SiC_(p)在镁合金熔体中的分散性,重点考察了发泡剂添加量(质量分数)和颗粒尺寸对镁基/SiC_(p)复合泡沫的密度、孔隙率和结构的影响.研究结果表明,通过熔体发泡法可制备出孔结构均匀、孔隙率高、缺陷相对较少、底部无实体层的镁基/SiC_(p)复合泡沫材料.热力学计算分析表明,经氧化处理后的SiC_(p)表面生成一层较薄的氧化膜,可与镁合金熔体发生化学反应形成冶金结合界面,有利于SiC_(p)的分散.发泡剂的添加量对试样的孔隙率和密度存在相对较大的影响,而发泡剂颗粒粒度对其影响相对较小.发泡剂的适宜添加量为3%,适宜平均粒度为110μm.The process of preparing Mg-based/SiCp composite foam by using melt foaming method with dolomite(the main component is MgCO_(3)) as foaming agent and silicon carbide particle(SiC_(p)) as viscosity increasing agent was studied. The combination of SiCp with Mg alloy melt and its dispersion in Mg alloy melt were analyzed. The effects of mass fraction and particle size of foaming agent on the density, porosity and structure of Mg based/SiC_(p)composite foam were investigated. The results show that Mg based/SiC_(p)composite foams can be prepared by using melt foaming method. Meanwhile, the Mg based/SiC_(p)composite foams have homogeneous pore structure, high porosity, relatively few defects and no solid layer at the bottom. Thermodynamic calculation and analysis show that a thin oxide film is formed on the surface of silicon carbide particles after oxidation treatment, which reacts with magnesium alloy melt to form metallurgical bonding interface, and it is conducive to the dispersion of silicon carbide particles. The results show that the content of foaming agent has a great influence on the porosity and density of the sample, the particle size of foaming agent has little effect on the porosity and density of the sample. The appropriate mass fraction of foaming agent is 3%, and the suitable average particle size is 110 μm.

关 键 词：熔体发泡法 镁基/SiC_(p)复合泡沫 SiC_(p)白云石 归一化法 

分 类 号：TB333[一般工业技术—材料科学与工程]