耐热钛基复合材料热变形行为及微结构演化研究  

Study on Thermal Deformation Behavior and Microstructure Evolution of Heat-resistant Titanium Matrix Composite

作　　者：刘莹莹 王富鑫 马小昭 张书铭 乔虹 付明杰 Liu Yingying;Wang Fuxin;Ma Xiaozhao;Zhang Shuming;Qiao Hong;Fu Mingjie(AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]中国航空制造技术研究院,北京100024

出　　处：《钛工业进展》2025年第1期21-30,共10页Titanium Industry Progress

摘　　要：研究了高温单道次等温压缩过程中耐热钛基复合材料MTi650A的动态流变行为,获得了高温应力–应变曲线,建立了材料的动态本构方程和热加工图,分析了热变形过程中材料的变形特性以及微结构演化规律。结果表明,随着变形温度的升高和应变速率的降低,MTi650A复合材料的稳态流变阶段延长,峰值流变应力呈明显下降趋势。在低温高应变速率下,材料稳态特征不明显,流变应力达到峰值后随应变增加持续减小,呈现出连续动态软化特征。MTi650A复合材料的有效加工窗口为(950~1150)℃/(0.01~1) s^(-1)。微观组织分析表明,MTi650A复合材料晶须增强相破碎程度主要受变形温度和应变速率影响,低温高应变速率更容易导致晶须破碎。β相区变形时,β相存在动态回复和再结晶,晶粒尺寸及α片层厚度变化与应变速率有关。The dynamic rheological behavior of heat-resistant titanium matrix composite MTi650A during single pass isothermal compression at high temperature was studied,and the stress-strain curve at high temperature was obtained.The dynamic constitutive equation and thermal working diagram of MTi650A composite were established,and the deformation characteristics and microstructure evolution law of the material during thermal deformation were analyzed.The results show that with the increase of deformation temperature and the decrease of strain rate,the steady state rheological stage of MTi650A composite is prolonged,and the peak rheological stress shows an obvious decreasing trend.At low temperature and high strain rate,the steady state characteristics of MTi650A composite are not obvious,and the rheological stress continues to decrease with the increase of strain after reaching the peak value,showing continuous dynamic softening characteristic.The effective processing window of MTi650A composite is(950-1150)℃/(0.01-1)s^(-1).The microstructure analysis shows that the degree of whisker breakage of MTi650A composite is mainly affected by deformation temperature and strain rate,and low temperature and high strain rate are more likely to cause whisker breakage.Theβphase has dynamic recovery and recrystallization,and the grain size and thickness ofαlayer are related to the strain rate.

关 键 词：耐热钛基复合材料 变形温度 应变速率 加工窗口 显微组织 

分 类 号：TG316[金属学及工艺—金属压力加工] TG146.23[一般工业技术—材料科学与工程]