短切碳纤维/AZ91D镁合金复合材料高温变形动态再结晶行为  

Dynamic recrystallization behavior of short carbon fiber/AZ91D Mg alloy composite during compression at evaluated temperature

作　　者：黄飚 王振军 邱旭东 余欢 徐志锋 HUANG Biao;WANG Zhenjun;QIU Xudong;YU Huan;XU Zhifeng(Key Discipline Laboratory of Light Alloy Processing Science and Technology, Nanchang Hangkong University, Nanchang 330063, China;Xiangyang Hangtai Power Machinery Factory, Xiangyang 441002, China)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室,南昌330063 [2]襄阳航泰动力机器厂,襄阳441002

出　　处：《复合材料学报》2018年第6期1525-1534,共10页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(51365043;51765045);江西省自然科学基金(20171BAB201021);江西省教育厅科学技术研究基金(GJJ1607055);江西省研究生创新专项基金(YC2015S319)

摘　　要：在变形温度为340~400℃、应变速率为0.001~0.1s-1、最大真应变为0.7的条件下,采用等温压缩实验研究了短切碳纤维(CFs)/AZ91D复合材料和AZ91D镁合金的动态再结晶行为。结果表明:CFs/AZ91D复合材料和AZ91D镁合金在高温压缩过程中均发生了显著的动态再结晶;CFs极大地促进了AZ91D基体的动态再结晶过程,减小了动态再结晶临界应变并细化了再结晶晶粒组织;AZ91D镁合金动态再结晶体积分数随应变量增加表现为典型的"S"型变化曲线,而CFs/AZ91D复合材料则呈现出快速增长-缓慢增长-趋于平稳的非线性变化规律。根据实验结果分别建立了CFs/AZ91D复合材料和AZ91D镁合金的动态再结晶临界应变模型和动力学模型,在此基础上分析了二者高温变形动态再结晶行为的差异。The dynamic recrystallization behavior of short carbon fiber（CFs）/AZ91 Dcomposite and AZ91 D Mg alloy was investigated by isothermal compressive experiment at the deformation temperatures from 340℃to 400℃,strain rates from 0.001 s^-1 to 1 s^-1 and a maximum true strain of 0.7.The results show that both CFs/AZ91 D composites and Mg alloy exhibit an obvious dynamic recrystallization during being compressed at elevated temperature.The addition of CFsgreatly promotes the dynamic recrystallization of the matrix alloy in the composite.As a result,the critical strain for dynamic recrystallization is reduced and a finer recrystallized grain structure is obtained in the composite.For the Mg alloy,the variation of volume fraction of dynamic recrystallization with the strain presents the classical＂S＂mode.For the CFs/AZ91 Dcomposites,however,the increase of volume fraction of dynamic recrystallization with the increase of strain exhibits a rapid-slow-stable behavior.The dynamic recrystallization critical strain and kinetics models of CFs/AZ91 Dcomposite and Mg alloy were developed according to the experimental results.Based on these models,the difference of the dynamic recrystallization behavior between CFs/AZ91 Dcomposite and Mg alloy was analyzed.

关 键 词：短切CF 复合材料 AZ91D镁合金 高温变形 动态再结晶 临界应变 动力学模型 

分 类 号：TB333[一般工业技术—材料科学与工程]