β相稳定元素对TiAl合金高温变形行为的影响
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摘要
利用Gleeble-1500D热模拟试验机研究了Ti-44Al、Ti-44Al-6Nb和Ti-44Al-6Nb-1Cr-2V合金在1 100～1 250℃和0. 01 s-1条件下的热变形行为。研究结果表明,添加β相稳定元素可降低TiAl合金的流变应力,在相同变形条件下Ti-44Al-6Nb-1Cr-2V合金具有更低的峰值应力。高温变形时,TiAl合金主要发生片层弯曲和拉长协调变形,以及片层团晶界处动态再结晶和B2相协调变形。动态再结晶程度随着变形温度的升高以及β相稳定元素含量的提高而增加,B2相协调变形和促进动态再结晶是TiAl合金的主要软化方式。添加β相稳定元素和控制B2相含量能有效改善TiAl合金热加工性能。
The hot deformation behavior of Ti-44Al,Ti-44Al-6Nb and Ti-44Al-6Nb-1Cr-2V alloys was studied on a Gleeble-1500D hot simulation machine at the temperature range of 1 100 ～ 1 250 ℃ and 0. 01 s~(-1). The results show that Ti-44Al-6Nb-1Cr-2V alloy shows the lower peak stress comparing to Ti-44Al alloy and Ti-44Al-6Nb alloy under the same deformation condition indicating that beta phase stabilizing elements can reduce flow stress of TiAl alloys significantly. The lamellar is bending and elongation to coordinate deformation during hot deformation,and dynamic recrystallization is mainly occurred at the lamellar colony. The dynamic recrystallization increases with the increase of the deformation temperature and beta phase stabilizing element content. B2 phase coordination deformation and promoting dynamic recrystallization are the main softening mechanism for TiAl alloys at high temperature. Thus addition of beta phase stabilizing elements and controlling of B2 phase can effectively improve the hot workability of TiAl alloys.
The hot deformation behavior of Ti-44Al,Ti-44Al-6Nb and Ti-44Al-6Nb-1Cr-2V alloys was studied on a Gleeble-1500D hot simulation machine at the temperature range of 1 100 ～ 1 250 ℃ and 0. 01 s~(-1). The results show that Ti-44Al-6Nb-1Cr-2V alloy shows the lower peak stress comparing to Ti-44Al alloy and Ti-44Al-6Nb alloy under the same deformation condition indicating that beta phase stabilizing elements can reduce flow stress of TiAl alloys significantly. The lamellar is bending and elongation to coordinate deformation during hot deformation,and dynamic recrystallization is mainly occurred at the lamellar colony. The dynamic recrystallization increases with the increase of the deformation temperature and beta phase stabilizing element content. B2 phase coordination deformation and promoting dynamic recrystallization are the main softening mechanism for TiAl alloys at high temperature. Thus addition of beta phase stabilizing elements and controlling of B2 phase can effectively improve the hot workability of TiAl alloys.
引文
[1] Cinca N,Lima C R C,Guilemany J M. An overview ofintermetallics research and application:status of thermalspray coatings[J]. Journal of Materials Research andTechnology,2013,2(1):75-86.
[2] Hrutkay K,Kaoumi D. Tensile deformation behavior of anickel based superalloy at different temperatures[J]. MaterialsScience and Engineering A,2014,599:196-203.
[3]林均品,陈国良. Ti Al基金属间化合物的发展[J].中国材料进展,2009,28(1):31-36.
[4]Clemens H,Kestler H. Processing and applications ofintermetallicγ-Ti Al-based alloys[J]. Advanced EngineeringMaterials,2000,2(9):551-570.
[5]陈玉勇,杨非,孔凡涛,等. Ti Al合金的热加工、组织和性能[J].中国材料进展,2010,29(3):12-18.
[6] Clemens H,Mayer S. Design,processing,microstructure,properties,and applications of advanced intermetallic Ti Alalloys[J]. Advanced Engineering Materials,2013,15(4):191-211.
[7]Gao S,Xu X,Shen Z,et al. Microstructure and propertiesof forged plasma arc melted pilot ingot of Ti-45Al-8. 5Nb-(W,B,Y)alloy[J]. Materials Science and EngineeringA,2016,677:89-96.
[8]孔凡涛,崔宁,陈玉勇,等. Ti-43A1-9V-Y合金的高温变形行为研究[J].金属学报,2013,49(11):1363-1368.
[9]Schwaighofer E,Clemens H,Lindemann J,et al. Hot-work-ing behavior of an advanced intermetallic multi-phaseγ-Ti Albased alloy[J]. Materials Science and Engineering A,2014,614:297-310.
[10]Niu H Z,Chen Y Y,Xiao S L,et al. Microstructure evolu-tion and mechanical properties of a novel betaγ-Ti Al alloy[J]. Intermetallics,2012,31:2 25-231.
[2] Hrutkay K,Kaoumi D. Tensile deformation behavior of anickel based superalloy at different temperatures[J]. MaterialsScience and Engineering A,2014,599:196-203.
[3]林均品,陈国良. Ti Al基金属间化合物的发展[J].中国材料进展,2009,28(1):31-36.
[4]Clemens H,Kestler H. Processing and applications ofintermetallicγ-Ti Al-based alloys[J]. Advanced EngineeringMaterials,2000,2(9):551-570.
[5]陈玉勇,杨非,孔凡涛,等. Ti Al合金的热加工、组织和性能[J].中国材料进展,2010,29(3):12-18.
[6] Clemens H,Mayer S. Design,processing,microstructure,properties,and applications of advanced intermetallic Ti Alalloys[J]. Advanced Engineering Materials,2013,15(4):191-211.
[7]Gao S,Xu X,Shen Z,et al. Microstructure and propertiesof forged plasma arc melted pilot ingot of Ti-45Al-8. 5Nb-(W,B,Y)alloy[J]. Materials Science and EngineeringA,2016,677:89-96.
[8]孔凡涛,崔宁,陈玉勇,等. Ti-43A1-9V-Y合金的高温变形行为研究[J].金属学报,2013,49(11):1363-1368.
[9]Schwaighofer E,Clemens H,Lindemann J,et al. Hot-work-ing behavior of an advanced intermetallic multi-phaseγ-Ti Albased alloy[J]. Materials Science and Engineering A,2014,614:297-310.
[10]Niu H Z,Chen Y Y,Xiao S L,et al. Microstructure evolu-tion and mechanical properties of a novel betaγ-Ti Al alloy[J]. Intermetallics,2012,31:2 25-231.