Hot Deformation Behavior, Dynamic Recrystallization, and Texture Evolution of Ti–22Al–25Nb Alloy

The hot deformation behavior, dynamic recrystallization, and texture evolution of Ti–22Al–25Nb alloy in the temperature range of 950–1050 °C and strain rate range of 0.001–1 s−1 is investigated by plane‐strain compression testing on the Gleeble‐3500 thermo‐mechanical simulator. The results show that the flow stress decreases with the increase of temperature and decrease of strain rate. Besides, the flow curves appear a serrate oscillation at a strain rate of 0.1 s−1 for all the temperature ranges, which may result from instability such as flow localization or micro‐cracking. The flow behavior can be expressed by the conventional hyperbolic sine constitutive equation and the calculated deformation activation energy Q in the (α2 + B2) and B2 regions are 631.367 and 304.812 kJ mol−1, respectively. The microstructure evolution is strongly dependent on the deformation parameters, and dynamic recrystallization (DRX) is the dominant softening mechanism in the (α2 + B2) region, including discontinuous dynamic recrystallization (DDRX), and continuous dynamic recrystallization (CDRX). In addition, the ηbcc‐fiber of {110} <001> is the dominant texture component in deformed Ti–22Al–25Nb alloy. It is observed that the weakening of the deformation texture is accompanied by the occurrence of DRX, which can be attributed to the large misorientation between DRX grains and neighboring B2 matrix induced by the rotation of DRX grains toward the preferred slip systems.

[1]  Ping Li,et al.  Developed constitutive models, processing maps and microstructural evolution of Pb-Mg-10Al-0.5B alloy , 2017 .

[2]  R. Dong,et al.  Characteristics of a hot-rolled near β titanium alloy Ti-7333 , 2017 .

[3]  Kai-feng Zhang,et al.  Microstructure evolution and dynamic recrystallization behavior of a powder metallurgy Ti-22Al-25Nb alloy during hot compression , 2017 .

[4]  R. Fu,et al.  Combined deformation behavior and microstructure evolution of 7050 aluminum alloy during hot shear-compression deformation , 2016 .

[5]  Fengbao Zhang,et al.  Cold deformation behavior of the Ti-15Mo-3Al-2.7Nb-0.2Si alloy and its effect on α precipitation and tensile properties in aging treatment , 2016 .

[6]  B. Tang,et al.  Texture evolution and dynamic recrystallization in a beta titanium alloy during hot-rolling process , 2015 .

[7]  Zhen Lu,et al.  Dynamic globularization kinetics of a powder metallurgy Ti–22Al–25Nb alloy with initial lamellar microstructure during hot compression , 2014 .

[8]  B. Tang,et al.  Characterization of hot deformation microstructure of a near beta titanium alloy Ti-5553 , 2014 .

[9]  B. Tang,et al.  An experimental study on the mechanism of texture evolution during hot-rolling process in a β titanium alloy , 2014 .

[10]  Y. Lin,et al.  Constitutive models for high-temperature flow behaviors of a Ni-based superalloy , 2014 .

[11]  B. Tang,et al.  Characterization of hot deformation behavior of a new near beta titanium alloy: Ti-7333 , 2013 .

[12]  Bin Tang,et al.  Deformation and dynamic recrystallization behavior of a high Nb containing TiAl alloy , 2013 .

[13]  B. Tang,et al.  Characteristics of metadynamic recrystallization of a high Nb containing TiAl alloy , 2013 .

[14]  Q. Pan,et al.  Characterization of flow behavior and microstructural evolution of Al–Zn–Mg–Sc–Zr alloy using processing maps , 2012 .

[15]  Yu Sun,et al.  A hybrid approach for processing parameters optimization of Ti-22Al-25Nb alloy during hot deformation using artificial neural network and genetic algorithm , 2011 .

[16]  Y. Lin,et al.  A critical review of experimental results and constitutive descriptions for metals and alloys in hot working , 2011 .

[17]  M. Jackson,et al.  The Flow Behavior and Microstructural Evolution of Ti-5Al-5Mo-5V-3Cr during Subtransus Isothermal Forging , 2009 .

[18]  A. Wu,et al.  A study on transient liquid phase diffusion bonding of Ti–22Al–25Nb alloy , 2009 .

[19]  D. Raabe,et al.  Texture inhomogeneity in a Ti–Nb-based β-titanium alloy after warm rolling and recrystallization , 2008 .

[20]  M. Hasegawa,et al.  Formation mechanism of texture during dynamic recrystallization in γ-TiAl, nickel and copper examined by microstructure observation and grain boundary analysis based on local orientation measurements , 2003 .

[21]  K. Tsuzaki,et al.  Continuous recrystallization in austenitic stainless steel after large strain deformation , 2002 .

[22]  D. Banerjee The intermetallic Ti2AlNb , 1997 .

[23]  T. Pollock,et al.  Effects of high temperature air and vacuum exposures on the room temperature tensile behavior of the (O + B2) titanium aluminide Ti-22Al-23Nb , 1996 .

[24]  D. Raabe,et al.  Relationship between rolling textures and shear textures in f.c.c. and b.c.c. metals , 1994 .

[25]  T. K. Nandi,et al.  A new ordered orthorhombic phase in a Ti3AlNb alloy , 1988 .

[26]  C. Sellars,et al.  On the mechanism of hot deformation , 1966 .

[27]  J. H. Hollomon,et al.  Effect of Strain Rate Upon Plastic Flow of Steel , 1944 .

[28]  A. Götte,et al.  Metall , 1897 .