摘要
采用连续变断面循环挤压对TC11合金进行变形,研究了变形温度、变形速度、变形道次对其沿径向显微组织及硬度分布的影响。结果表明：在再结晶温度附近变形时,α相尺寸减小并呈等轴状,晶粒细化显著;而在较高温度变形时,晶粒细化效果变差。同时,变形速度对α相形貌影响较大,速度较低时,初生α相呈长条状,而当速度较高时,初生α相呈等轴状,且分布均匀。变形温度和变形速度对TC11合金沿径向的显微硬度分布有一定影响,试样经不同工艺参数变形后,同一试样沿径向的显微硬度值差异较小且分布较均匀,这与晶粒细化程度较好有关。采用连续变断面循环挤压制备TC11细晶材料时的较佳工艺参数为：850℃,5 mm/s,6道次,α相晶粒尺寸为4～4.5μm,且分布均匀。
TC11 titanium alloy was deformed by continuous variable cross-section recycled extrusion（CVCE）,and the effects of deformation temperature,speed and number of the extrusion cycles on microstructure and microhardness of the alloy were investigated.The results show that deforming near the recrystallization temperature,the grain size of α phase becomes smaller and it is significantly refined to the equiaxed shape,but at higher deformation temperature,the refinement degree becomes weakened.In addition,the deformation speed has a great influence on the morphology of α phase.The primary α phase grain is elongated when the specimen is deformed at lower speed.While the primary α phase shows the equiaxed and homogeneous distribution when it is deformed at higher speed.The deformation temperature and speed have effect on the microhardness distribution along the radius of the TC11 specimen.The similar microhardness distribution along the radius of the specimen under the different processing parameters is observed due to the better refinement of the grains.The optimum CVCE parameters for producing fine grained TC11 titanium alloy is obtained based on the experiment.When the TC11 alloy is deformed at 850 ℃ with 5 mm / s for 6 cycles,the size of the primary α phase is 4-4.5 μm,and the microstructure is distributed homogeneously.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2016年第6期43-48,共6页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(51101116)
2015国家大学生创新创业训练项目(201510703130)
关键词
TC11合金
连续变断面循环挤压
显微组织
晶粒细化
TC11 titanium alloy
continuous variable cross-section recycled extrusion
microstructure
grain refinement
