论文信息 - Acceleration of grain boundary motion in Al by small additions of Ga

Acceleration of grain boundary motion in Al by small additions of Ga

Abstract The temperature dependence of 〈111〉 tilt grain boundaries with angles of misorientation of 38·2° and 40·5° was investigated in bicrystals of both pure (99·999%) Al and the same Al doped with 10ppmGa in the temperature regime between 400 and 580°C. The grain boundary mobility for the investigated grain boundaries over the entire investigated temperature range is enhanced by minor additions of Ga. Both the activation enthalpy and the pre-exponential factor are affected by Ga doping. The orientation dependence of grain boundary mobility is strongly reduced but not completely removed. The drastic rise in grain boundary mobility by the addition of Ga to pure Al is interpreted as a consequence of a change in the boundary structure and the mechanism of boundary migration owing to a pre-wetting phase transition and formation of a liquid (or quasiliquid) Ga-rich layer on the grain boundary.

[1] U. Czubayko,et al. An X-ray device for continuous tracking of moving interfaces in crystalline solids , 1995 .

[2] V. Sursaeva,et al. Orientation relationships between grains and grain boundaries in Al‐1 wt% Ga at the beginning of secondary recrystallization , 1995 .

[3] U. Czubayko,et al. Mobility of 〈111〉 tilt grain boundaries in the vicinity of the special misorientation ∑=7 in bicrystals of pure aluminium , 1995 .

[4] D. Molodov,et al. Effect of pressure on grain boundary migration in aluminium bicrystals , 1994 .

[5] E. Rabkin,et al. Grain Boundaries: Phase Transitions and Critical Phenomena , 1993 .

[6] G. Gottstein,et al. On the orientation dependence of grain boundary migration , 1992 .

[7] H. Westengen,et al. On the effect of solute atoms on grain-boundary migration , 1978 .

[8] Mats Hillert,et al. A treatment of the solute drag on moving grain boundaries and phase interfaces in binary alloys , 1976 .

[9] H. Gleiter. Theory of grain boundary migration rate , 1969 .

[10] John W. Cahn,et al. The Impurity‐Drag Effect in Grain Boundary Motion , 1962 .

[11] K. Lücke,et al. A quantitative theory of grain-boundary motion and recrystallization in metals in the presence of impurities , 1957 .

[12] D. Clarke. On the Equilibrium Thickness of Intergranular Glass Phases in Ceramic Materials , 1987 .

[13] F. Haessner. Recrystallization of metallic materials , 1978 .