In this study,the effect of temperatures and cooling rates of heat treatment on the microstructure of a powder metallurgy (PM) Ti-46Al-2Cr-2Nb-(B,W) (at.％) alloy was studied.Depending on the cooling rate and temperature,the different structures were obtained from the initial near-γ (NG) microstructures by heat treatment in the α+γ field.The results show that the microstructures of samples after furnace cooling (FC) consist primarily of equiaxed γ and α2 grains,with a few grains containing lamellae.Duplex microstructures consist mainly of γ grains and lamellar colonies were obtained in the quenching into another furnace at 900℃ (QFC) samples.However,further increasing of the cooling rate to air cooling (AC) induces the transformation of α→α2 and results in a microstructure with equiaxed γ and α2 grains,and no lamellar colonies are found.
参考文献
| [1] | Kim Y.W .Progress in the understanding of gamma titanium aluminides[J].JOM-Journal of the Minerals Metals and Materials Society,1991,43(08):40. |
| [2] | Takeyama M .Microstructural evolution and tensile properties of titanium-rich TiAl alloy[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,1992,152(1-2):269. |
| [3] | Yanqing Su;Xinwang Liu;Liangshun Luo;Long Zhao;Jingjie Guo;Hengzhi Fu .Deoxidation of Ti-Al intermetallics via hydrogen treatment[J].International journal of hydrogen energy,2010(17):9214-9217. |
| [4] | Su Y.Q;Liu C;Li X.Z;Guo J.J Li B.S Jia J and Fu H.Z .Microstructure selection during the directionally peritectic solidification of Ti-Al binary system[J].Intermetallics,2005,13(3-4):267. |
| [5] | Su Y.Q;Guo J.J;Jia J;Liu G.Z and Liu Y .Composition control of a TiAl melt during the induction skull melting(ISM)process[J].Journal of Alloys and Compounds,2002,334(1-2):261. |
| [6] | Kim Y.W .Ordered intermetallic alloys,part Ⅲ:gamma titanium aluminides[J].JOM-Journal of the Minerals Metals and Materials Society,1994,46(07):30. |
| [7] | LU Xin,ZHU Langping,LIU Chengcheng,ZHANG Lin,WU Mao,QU Xuanhui.Fabrication of micro-fine high Nb-containing TiAl alloyed powders by fluidized bed jet milling[J].稀有金属（英文版）,2012(01):1-6. |
| [8] | Kim Y.W .Intermetallic alloys based on gamma titanium aluminide[J].JOM-Journal of the Minerals Metals and Materials Society,1989,41(07):24. |
| [9] | Toshimitsu T .Manufacturing technology for gamma-TiAl alloy in current and future applications[J].Rare Metals,2011,30(z1):294. |
| [10] | R.M. Imayev;V.M. Imayev;M. Oehring .Alloy design concepts for refined gamma titanium aluminide based alloys[J].Intermetallics,2007(4):451-460. |
| [11] | Yang S.H;Kim W.Y;Kim M.S .Fabrication of unidirectional porous TiAl-Mn intermetallic compounds by reactive sintering using extruded powder mixtures[J].Intermetallics,2003,11(08):849. |
| [12] | Chu W.Y;Thompson A.W .Effect of grain size on yield strength in TiAl[J].Scripta Metallurgica,1991,25(03):641. |
| [13] | Koeppe C;Bartels C;Seege J;Mecking H .General aspects of the thermomechanical treatment of two-phase intermetallic TiAl compounds[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1993,24A(08):1795. |
| [14] | Arno B;Carsten K;Heinrich M .Microstructure and properties of Ti-48Al-2Cr after thermomechanical treatment[J].Materials Science and Engineering A,1995,192-193(01):226. |
| [15] | Zhang G;Blenkinsop P.A;Wise M.L.H .Phase transformations in HIPed Ti-48Al-2Mn-2Nb powder during heat-treatments[J].Intermetallics,1996,4(06):447. |
| [16] | H. M. Flower;J. Christodoulou .Phase equilibria and transformations in titanium aluminides[J].Materials Science and Technology: MST: A publication of the Institute of Metals,1999(1):45-52. |
| [17] | Denquin A;Naka S .Phase transformation mechanism involved in two phase TiAl-Ⅱ:discontinuous coarsening and massive-type transformation[J].Acta Metallurgica,1996,44(01):353. |
| [18] | Kim Y.W .Microstructural evolution and mechanical properties of a forged gamma titanium aluminide alloy[J].Acta Metallurgica Et Materialia,1992,40(06):1121. |
| [19] | Aaronson H.I .Atomic mechanisms of diffusional nucleation and growth and comparisons with their counterparts in shear transformations[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1993,24(02):241. |
| [20] | Mishin Y;Herzig C .Dision in the Ti-Al system[J].Acta Metallurgica,2000,48(02):589. |
| [21] | Denquin A;Naka S .Phase transformation mechanism involved in two phase TiAl-(Ⅰ):lamellar structure formation[J].Acta Metallurgica,1996,44(01):343. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%