摘要
利用Gleeble-3500热模拟试验机,对电子束冷床熔铸制备的Ti-6Al-4V(TC4)钛合金在变形温度为850~1000℃、应变速率为0.01~1 s^-1和总变形量为50%条件下进行多道次热压缩模拟实验,研究铸态合金的多道次压缩热变形行为及微观组织演变规律。结果表明:合金的流变应力随变形温度的升高和应变速率的降低均呈降低趋势;不同变形温度下随应变速率的降低,合金的软化率逐渐升高,且变形温度越高,各道次间软化率趋于稳定;在变形温度950~1000℃、应变速率0.01~0.1 s^-1范围内合金的组织均得到不同程度的细化和均匀化,并发生动态回复与再结晶现象,此变形参数下合金的热加工性能稳定,可为电子束冷床熔铸TC4合金的铸态直接多道次热轧成形提供指导。
The multi-pass hot compression simulation experiment of Ti-6 Al-4 V(TC4)titanium alloy prepared by electron beam cold hearth melting technology was carried out on a Gleeble-3500 thermal simulation machine under the conditions of deformation temperature of 850-1000℃,strain rate of 0.01-1 s^-1 and total deformation of 50%,and the hot compression deformation behavior and microstructure evolution of the as-cast alloys during the multi-pass compression were studied.The results show that the flow stress of the alloy decreases with the increase of deformation temperature and the decrease of strain rate,the softening rate of the alloy increases gradually with the decrease of strain rate at different deformation temperatures,and the higher the deformation temperature,the softening rate tends to be stable among the passes.When the deformation temperature is 950-1000℃ and the strain rate is 0.01-0.1 s^-1,the microstructure of the alloy is refined and homogenized,and the phenomenon of dynamic recovery and recrystallization occurs.Under this deformation parameter,the thermal processing property of the alloy is stable,which can provide guidance for the direct multi-pass hot rolling forming of the cast TC4 alloy prepared by electron beam cold hearth melting technology.
作者
胡亚美
黄海广
郑必举
史亚鸣
张玉勤
蒋业华
HU Ya-mei;HUANG Hai-guang;ZHENG Bi-ju;SHI Ya-ming;ZHANG Yu-qin;JIANG Ye-hua(School of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China;National Local Joint Engineering Laboratory for Advanced Solidification Forming and Equipment Technology,Kunming 650093,China;Yunnan Titanium Application Product Engineering Technology Research Center,Chuxiong 651209,China)
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2020年第6期39-46,共8页
Transactions of Materials and Heat Treatment
基金
国家重点研发计划项目(2016YFB0301200)。
关键词
TC4合金
电子束冷床熔铸
多道次热变形
软化机制
微观组织
TC4 alloy
electron beam cold hearth melting
multi-pass compression
softening mechanism
microstructure
