3D PHASE FIELD SIMULATION OF EFFECT OF INTERFACIAL ENERGY ANISOTROPY ON SIDEPLATE GROWTH IN Ti–6Al–4V

The effect of interface energy anisotropy on the sideplate growth in Ti-6A1-4V is studied using 3D quantitative phase field method.The dynamic and thermodynamic data come from the DICTRA and Thermo-Calc databases,respectively.The results show that the interface anisotropy is an important factor controlling the shape of plates.Larger interface energy anisotropy results in wider plates and thicker residual /3 phase.Statistics of plate width,thickness and inter-platelet /? phase thickness show that the evolutions of the width to thickness ratio of sideplate are different for systems with different interface energy anisotropy ratios.Solute concentrations are found inhomogeneous in the /? phase near a/0 interface(Al-poor and V-rich).The stronger the interface energy anisotropy is,the greater of the inhomogeneity.Higher temperatures result in slower growth,forming wider and thicker plates.

[1]  H. Fraser,et al.  Crystallographic and morphological relationships between β phase and the Widmanstätten and allotriomorphic α phase at special β grain boundaries in an α/β titanium alloy , 2007 .

[2]  A. Gysler,et al.  The effect of grain size on the fatigue crack propagation behavior of age-hardened alloys in inert and corrosive environment , 1979 .

[3]  S. Semiatin,et al.  Effect of initial microstructure on plastic flow and dynamic globularization during hot working of Ti-6Al-4V , 1999 .

[4]  F. Zhang,et al.  Predicting phase equilibrium, phase transformation, and microstructure evolution in titanium alloys , 2005 .

[5]  H. Fraser,et al.  Precipitation of grain boundary α in a laser deposited compositionally graded Ti–8Al–xV alloy – an orientation microscopy study , 2004 .

[6]  H. Margolin,et al.  The mechanism of void formation, void growth, and tensile fracture in an alloy consisting of two ductile phases , 1972 .

[7]  Thomas R. Bieler,et al.  The effect of alpha platelet thickness on plastic flow during hot working of TI–6Al–4V with a transformed microstructure , 2001 .

[8]  Yunzhi Wang,et al.  Quantitative phase field modeling of diffusion-controlled precipitate growth and dissolution in Ti–Al–V , 2004 .

[9]  S. Semiatin,et al.  The kinetics of static globularization of Ti-6Al-4V , 2002 .

[10]  W. Soboyejo,et al.  An investigation of the effects of microstructure and stress ratio on fatigue crack growth in Ti–6Al–4V with colony α/β microstructures , 2004 .

[11]  J. Ågren,et al.  On the formation of Widmanstätten ferrite in binary Fe–C – phase-field approach , 2004 .

[12]  Jan Sieniawski,et al.  The effect of microstructure on the mechanical properties of two-phase titanium alloys , 1997 .

[13]  D. Kinderlehrer,et al.  Morphological Stability of a Particle Growing by Diffusion or Heat Flow , 1963 .

[14]  H. Aaronson,et al.  Influence of austenite grain sile upon the lidmanstatten-start (ls) temperature for the proeutectoid ferrite reaction , 1972 .

[15]  G. R. Yoder,et al.  Quantitative analysis of microstructural effects on fatigue crack growth in widmanstätten Ti-6A1-4V and Ti-8Al-1Mo-1V , 1979 .

[16]  I. W. Hall,et al.  Fracture toughness and crack propagation in titanium alloys , 1978 .

[17]  K. Ravichandran.  Near threshold fatigue crack growth behavior of a titanium alloy: Ti-6A1-4V , 1991 .

[18]  S. Semiatin,et al.  Mechanisms of globularization of Ti-6Al-4V during static heat treatment , 2003 .