固溶温度对Ti-22Al-24Nb合金显微组织的影响
|
摘要
研究了经开坯锻造的Ti-22Al-24Nb合金在不同固溶温度下的显微组织变化规律。结果显示:开坯锻造后Ti-22Al-24Nb合金的显微组织为等轴三相(α_2+B2+O)组织。随固溶温度的升高,初生板条状O相和等轴α_2相转变为B2基体相,B2相的体积分数逐渐增大。当固溶温度为1000℃时,B2相发生再结晶,出现了细小晶粒组织。固溶温度升高到1040℃时,晶粒明显长大,达200μm左右,且未溶解的初生α_2/O相也有所长大。油冷过程中,由于再结晶时间充分,晶粒变大。
The microstructure changing rules of Ti-22Al-24 Nb alloy after billet forging at different solution temperatures were studied. The results indicate that the microstructure of Ti-22Al-24 Nb alloy after billet forging is three phases(α_2+O+B2)microstructure with equiaxial grains. With the increase of solution temperature, the primary lath O phase and isometric α_2 phase change into B2 matrix phase, and the volume fraction of B2 phase increases gradually. When the solution temperature is1000℃, the B2 phase recrystallizes, and fine grain microstructure appears. When the solution temperature increases to 1040℃, the grain size significantly increases, reaching 200 μm or so, and the undissolved α_2/O phase also grows. In process of the oil cooling, the recrystallized grains become larger as the time is sufficient.
The microstructure changing rules of Ti-22Al-24 Nb alloy after billet forging at different solution temperatures were studied. The results indicate that the microstructure of Ti-22Al-24 Nb alloy after billet forging is three phases(α_2+O+B2)microstructure with equiaxial grains. With the increase of solution temperature, the primary lath O phase and isometric α_2 phase change into B2 matrix phase, and the volume fraction of B2 phase increases gradually. When the solution temperature is1000℃, the B2 phase recrystallizes, and fine grain microstructure appears. When the solution temperature increases to 1040℃, the grain size significantly increases, reaching 200 μm or so, and the undissolved α_2/O phase also grows. In process of the oil cooling, the recrystallized grains become larger as the time is sufficient.
引文
[1]Banerjee D,Gogia A K,Nandy T K,et al.A new odered orthorhombic phasein a Ti3Al-Nb alloy[J].Acta Metallurgica,1988,36(4):871-882.
[2]梁晓波,程云君,张建伟,等.热处理对β锻造Ti-22Al-25Nb合金组织和性能的影响[J].中国有色金属学报,2010,20(S1):611-615.
[3]毛勇,李世琼,张建伟,等.Ti-22Al-20Nb-7Ta合金的显微组织和力学性能研究[J].金属学报,2000,36(2):135-140.
[4]Zhang J W,Chen Y Y,Si Y F,et al.Effects of yttrium O microstructures andproperties of Ti-17Al-27Nb alloy[J].Trans.Nonfer.Met.Soc.China,2006,16(2):316-320.
[5]Nandy T K,Banerjee D.Creep of the orthorhombic phase based on theintermetallic Ti2Al Nb[J].Intermetallics,2000,8(5/6):915-928.
[6]Emura S,Araoka A,Hagiwara M.B2 grain size refinement and its effect on roomtemperature tensile properties of a Ti-22Al-27Nb orthorhombic intermetallic alloy[J].Scr.Mater,2003,48(5):629-634.
[7]Cowen C J,Boehlert C J.Microstructure,Creep,and tensile behavior of a Ti-21Al-29Nb(at%)orthorhombic+B2 Alloy[J].Intermetallics,2006,14(4):412-422.
[2]梁晓波,程云君,张建伟,等.热处理对β锻造Ti-22Al-25Nb合金组织和性能的影响[J].中国有色金属学报,2010,20(S1):611-615.
[3]毛勇,李世琼,张建伟,等.Ti-22Al-20Nb-7Ta合金的显微组织和力学性能研究[J].金属学报,2000,36(2):135-140.
[4]Zhang J W,Chen Y Y,Si Y F,et al.Effects of yttrium O microstructures andproperties of Ti-17Al-27Nb alloy[J].Trans.Nonfer.Met.Soc.China,2006,16(2):316-320.
[5]Nandy T K,Banerjee D.Creep of the orthorhombic phase based on theintermetallic Ti2Al Nb[J].Intermetallics,2000,8(5/6):915-928.
[6]Emura S,Araoka A,Hagiwara M.B2 grain size refinement and its effect on roomtemperature tensile properties of a Ti-22Al-27Nb orthorhombic intermetallic alloy[J].Scr.Mater,2003,48(5):629-634.
[7]Cowen C J,Boehlert C J.Microstructure,Creep,and tensile behavior of a Ti-21Al-29Nb(at%)orthorhombic+B2 Alloy[J].Intermetallics,2006,14(4):412-422.