双尺寸SiCp/AZ91镁基复合材料组织稳定性及高温变形行为研究

项目名称： 双尺寸SiCp/AZ91镁基复合材料组织稳定性及高温变形行为研究

项目编号： No.51201112

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 金属材料学科

项目作者： 邓坤坤

作者单位： 太原理工大学

项目金额： 25万元

中文摘要： 本课题拟就(亚微米+微米)双尺寸颗粒增强镁基复合材料组织稳定性及高温变形行为进行进行研究，通过优化热变形工艺，制备出晶粒细小、颗粒分布均匀且力学性能较高的双尺寸SiCp/AZ91复合材料。分析亚微米和微米SiCp体积比、微米SiCp尺寸对复合材料显微组织和力学性能的影响规律。研究双尺寸SiCp/AZ91复合材料经不同退火工艺后的晶粒尺寸、微观结构和力学性能，建立基于温度和时间的细晶镁基复合材料组织稳定区间，揭示双尺寸颗粒对细晶镁基体组织稳定性的影响规律。在此基础上，研究细晶镁复合材料高温压缩变形后的微观结构和性能。通过分析复合材料在高温变形过程中的组织演化，揭示双尺寸颗粒对细晶镁基体动态再结晶行为的影响机制；计算细晶镁基复合材料的变形热激活能和应力指数，揭示双尺寸颗粒对细晶镁基复合材料高温变形行为的影响机理。本研究对高强镁基复合材料的开发、显微组织和力学性能控制，具有重要的理论意义。

中文关键词： 细晶镁基复合材料；热稳定性；动态再结晶；热变形机理；双尺寸SiCp

英文摘要： The aim of this project is to investigate the microstructure stability and elevated temperature deformation behavior of bimodal size particle reinforced magnesium matrix composite. By optimizing deformation process, it is hoped to obtain the bimodal size SiCp/AZ91 magnesium matrix composites with fine grains, uniform particle distribution and higher mechanical properties. The effect of micron SiCp size as well as the volume ratio between submicron and micron SiCp on the microstructure and mechanical properties of magnesium matrix composite is analyzed. The grain size, microstructure and mechanical properties of bimodal size SiCp/AZ91 magnesium matrix composite influenced by different annealing process is researched, thus the microstructure stability interval can be constructed based on temperature and time, which is help to illustrate the influence of bimodal size particles on microstructure stability of fine-grained magnesium matrix. Based on above analysis, the microstructure and properties of fine-grained magnesium matrix composite after elevated temperature compression are investigated. The dynamic recrystallization mechanism of fine-grained magnesium matrix influenced by bimodal size particles will be illustrated through the way of investigating the microstructure evolution of fine-grained magnesium matrix

英文关键词： Fine-grained magnesium matrix composite；Thermal stability；Dyanmic recrystallization；Hot deformation mechanism；Bimodal size SiCp