摘要
以电子束冷床(EB)炉单次熔铸的TA10钛合金扁锭为研究对象,利用Gleeble−3800热模拟试验机开展高且宽应变速率范围(0.01~30 s^(−1))下的等温压缩试验,研究该合金在800~1000℃下变形60%时的高温力学行为及铸态组织演变特征,建立基于峰值应力的高温塑性本构方程,绘制考虑应变的热加工图,深入讨论能量耗散效率因子与宏观、微观组织、力学响应间的关联关系。结果表明:随着变形温度升高或应变速率降低,TA10钛合金流变应力减小;变形温度高于或低于相变点时,峰值应力与变形温度均呈线性相关。Arrhenius方程能较好地预测该合金变形抗力与工艺参数间的变化规律。该合金不适合单道次大变形,较为适合变形量中等且较慢应变速率下的成形方式,可尝试开展高速率多次小变形的方式成形。该合金在两相区慢应变速率下热变形时的流变软化机制为动态球化或塑性流动局部化,而高应变速率下应力塌陷现象的主要原因为宏观失稳,且其在单相区的软化机制以动态回复为主。
TA10 titanium alloy is currently known as the most competitive corrosion-resistant titanium alloy.This alloy plate ingots obtained from single melting in an electron beam cooling bed(EB)furnace were regarded as the research object.Isothermal compression tests within a high and wide strain rate range(0.01−30 s^(−1))were carried out on the Gleeble−3800 thermomechanical simulator to investigate the high-temperature mechanical behavior characteristics and the as-cast macro-and micro-structural evolutions of the tested alloy at deformation amount of 60%under temperature range from 800℃to 1000℃.The high-temperature plastic constitutive equation based on peak stress was established.Hot processing maps considering strain were constructed to deeply discuss the relationship between the energy dissipation efficiency factor and the macro-/micro-structure,as well as the mechanical response.The results reveal that the flow stress of TA10 titanium alloy decreases with increasing deformation temperature or decreasing strain rate.The peak stress exhibits a linear relationship with the deformation temperature when the deformation temperature is above or below theβtransus temperature.The Arrhenius equation is proven effective in predicting the variation in deformation resistance based on process parameters for this alloy.It is recommended to use this alloy for forming processes with medium deformation amounts and lower strain rates,while avoiding single-pass large deformation amounts.Alternatively,high-speed and multiple-pass small deformation amount methods can be explored for forming purposes.Additionally,it is determined that the flow softening mechanism of this alloy during hot deformation at lower strain rates in the two-phase region involves dynamic globularization or plastic flow localization.However,in the case of hot deformation at higher strain rates,the main reason for the phenomenon of stress collapse is macro instability.Lastly,it is found that the softening mechanism in the single-phase region is primarily due to dynamic recovery.
作者
张启飞
储双杰
梁高飞
杨帅
王美晨
毛博
ZHANG Qifei;CHU Shuangjie;LIANG Gaofei;YANG Shuai;WANG Meichen;MAO Bo(School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China;Baowu Special Metallurgy Co.,Ltd.,Shanghai 200940,China;Western Metal Materials Co.,Ltd.,Xi’an 710201,China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2024年第5期1555-1565,共11页
The Chinese Journal of Nonferrous Metals
基金
国家重点研发计划资助项目(2022YFB3705603)
上海市科研计划资助项目(22SQBS00600)。
关键词
TA10钛合金
高温力学行为
铸态组织演变
高温塑性本构方程
热加工图
TA10 titanium alloy
high temperature mechanical behavior
macro-and micro-structural evolution
high-temperature plastic constitutive equation
hot processing map
