Influence of liquid-phase inclusion on high-temperature deformation behavior in Al-Bi alloys

Tensile properties of an Al-3.4mass% Bi alloy up to 700 K were studied to understand the effects of the liquid Bi phase. Strain-rate sensitivity near the melting point of Bi was found to take values in a range of 0.17-0.31. Elongation showed a maximum value slightly above the melting temperature, indicating that the liquid phase could enhance tensile elongation in the AI-Bi alloy. Above the melting temperature, the dislocation density was found to decrease and the increment of the cavity volume fraction with strain slowed down in comparison to the results below the melting temperature. The increase of the tensile elongation was attributed to an efficient stress accommodation mechanism provided by the liquid phase. (C) 1997 Elsevier Science S.A.