摘要
对机械合金化制备的Ａｌ_４Ｃ_３、Ａｌ_２Ｏ_３弥散质点和ＳｉＣ颗粒复合强化Ａｌ基复合材料进行了拉伸试验和断口分析，并测定了弹性模量和热膨胀系数．研究表明，在ＳｉＣ_ｐ／Ａｌ复合材料中引入弥散的Ａｌ_４Ｃ_３和Ａｌ_２Ｏ_３质点可以明显提高复合材料的室温和高温强度，随加入Ｃ含量的增加或Ａｌ粉氧化时间的加长，复合材料的强度提高．在Ａｌ_４Ｃ_３／Ａｌ复合材料的基础上加入ＳｉＣ颗粒可以提高复合材料的弹性模量并进一步降低其热膨胀系数．复合材料断口为大韧窝加细小韧窝的混合断口，随复合材料基体强度的增加，拉伸断口上断裂的ＳｉＣ颗粒数量增多．
The tenisle tests and fracture surface analyses on the Al_4C_3. Al_2O_3 dispersoids and SiC particulate strengthened aluminum composites fabricated by mechanical alloying were carried out, as well as elastic modulus and CTE of the composites were measured.It was indicated that the strength of SiC_p/ Al composites is obviously improved due to the formation of Al_4C_3 and Al_2O_3 dispersoids, and increases with increasing C content or oxidation time of aluminum powder. The elevated temperature strength of Al_4C_3 dispersoid and SiC particulate reinforced aluminum composite is superior to that of SiC whisker reinforced 2024Al composite. The elastic modulus of Al_4C_3/ Al composite is raised due to the addition of SiC particulates, and CTE is reduced further.The fracture surfaces of the composites display mixture type of large dimples and fine dimples. The amount of cracked SiC particulates on tensile fracture surfaces of the compsites increases with increasing the strength of compsite matrix.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1994年第1期B033-B038,共6页
Acta Metallurgica Sinica
基金
国家863计划
关键词
铝基
复合材料
碳化硅
断裂特征
compsite
Al
SiC
Al_4C_3
Al_2O_3
fracture behaviour
