摘要
对搅拌铸造法制备的SiCp/2024Al复合材料超塑性的预处理、力学行为、微观结构及变形机制进行了研究,结果表明,合适的强烈塑性变形是改善复合材料组织进而提高超塑性的有效方法:经小挤压、热轧和冷轧后,在温度为823K、初始应变速率为 1.1×10-3 s-1的拉伸变形条件下,超塑延伸率为405%,超塑变形机制为晶粒的适度长大、动态连续再结晶和适当的微量液相共同协调的晶界滑动:液相不是该复合材料展现超塑性的必要条件。
The superplastic pretreatment, mechanical behavior, microstructure and deformation mechanism of SiCp/2024Al composite fabricated by stirring casting were investigated. The results showed that severe plastic deformation is an effective way of improving microstructure and superplasticity of the composite. After extruded with a low extrusion ratio of 10:1, hot rolled and cold rolled, the composite exhibited a elongation of 405% at the initial strain rate of 1.1 X 10(-3) s(-1) at 823 K, and the superplastic deformation mechanisms were grain boundary sliding accommodated by a moderate grain growth, dynamic continuous recrystallization and a small amount of liquid phase. Liquid phase is not indispensable condition for the composite superplasticity.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第5期544-548,共5页
Acta Metallurgica Sinica
基金
国家自然科学资金项目59631080资助
