In the present work, the hot workability and microstructural evolution of NiTi47.TCu6.3 （at.%） shape memory alloy were investigated by using wedge-rolling test. The wedge specimens were subjected to hot rolling at the temperatures of 700-1000℃. The microstructural evolutions at the strains of 0.05, 0.15, 0.2, 0.25 and 0.3 were then characterized by optical microscopy and scanning electron microscopy （SEM） as well as energy dispersive spectrometry （EDS） technique. Depending on the deformation temperature and strain, the dynamic recrystallization （DRX） could occur, leading to the refining of the microstructure. At low temperatures of 700 and 800℃ there was no sign of DRX at all studied strains. At these temperatures, the formed fine needle-like precipitates pinned the grain boundaries and prevented them from bulging/migration. By contrast, at higher temperatures of 900 and 1000℃, the DRX took place at the critical strains lower than 0.25 and 0.15, respectively. However, at higher temperatures, strain-induced-boundary-migration （SIBM） mechanism resulted in the formation of DRX grains.
参考文献
| [1] | J. Frenzel;Z. Zhang;K. Neuking .High quality vacuum induction melting of small quantities of NiTi shape memory alloys in graphite crucibles[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2004(1/2):214-223. |
| [2] | G.S. Firstov;J. Van Humbeeck;Y.N. Koval .High-temperature shape memory alloys Some recent developments[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2004(1/2):2-10. |
| [3] | T. Kurita;H. Matsumoto;H. Abe .Transformation behavior in rolled NiTi[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2004(1/2):158-161. |
| [4] | S.K. Sadrnezhaad;S.H. Mirabolghasemi .Optimum temperature for recovery and recrystallization of 52Ni48Ti shape memory alloy[J].Materials & Design,2007(6):1945-1948. |
| [5] | A.S. Paula;K.K. Mahesh;F.M. Braz Fernandes.Evolution of phase transformations after multiple steps of marforming in Ti-rich Ni-Ti SMA[J].The European physical journal: Special topics,2008:45-51. |
| [6] | A.S. Paula;K.K. Mahesha;C.M.L. dos Santos;F.M. Braz Fernandes;C.S. da Costa Viana.Thermomechanical behavior of Ti-rich NiTi shape memory alloys[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008:146-150. |
| [7] | M. Morakabati;Sh. Kheirandish;M. Aboutalebi .The effect of Cu addition on the hot deformation behavior of NiTi shape memory alloys[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2010(1):57-62. |
| [8] | K. Dehghani;A.A. Khamei .Hot deformation behavior of 60Nitinol (Ni60 wt%CTi40 wt%) alloy:Experimental and computational studies[J].Materials Science & Engineering. A, Structural Materials: Properties, Misrostructure and Processing,2010(3):684-690. |
| [9] | A.A. Khamei;K. Dehghani .Modeling the hot-deformation behavior of Ni_(60 wt%)-Ti_(40 wt%) intermetallic alloy[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2010(1/2):377-381. |
| [10] | Ch. Grossmann;J. Frenzel;V. Sampath;T. Depka;A. Oppenkowski;Ch. Somsen;K. Neuking;W. Theisen;G. Eggeler .Processing And Property Assessment Of Niti And Niticu Shape Memory Actuator Springs[J].Materialwissenschaft und Werkstofftechnik,2008(8):499-510. |
| [11] | I. Schindler;P. Suchanek;S. Rusz .HOT-CRACKING OF HIGH-ALLOYED STEELS EVALUATED BY WEDGE ROLLING TEST[J].Strength of materials,2008(1):52-55. |
| [12] | H. ROSNER;P.SCHLOBMACHER;A.V. SHELYAKOV .THE INFLUENCE OF COHERENT TICU PLATE-LIKE PRECIPITATES ON THE THERMOELASTIC MARTENSITIC TRANSFORMATION IN MELT-SPUN Ti_(50)Ni_(25)Cu_(25) SHAPE MEMORY ALLOYS[J].Acta materialia,2001(9):1541-1548. |
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