The heat treatment, including two steps, was proposed to obtain Fine Fully Lamellar (FFL) microstructure on TiAl containing minor Ni. The first step was in (a+y) phase region to get Duplex (DP) microstructure, and the...The heat treatment, including two steps, was proposed to obtain Fine Fully Lamellar (FFL) microstructure on TiAl containing minor Ni. The first step was in (a+y) phase region to get Duplex (DP) microstructure, and the second step was in a phase region transforming DP microstructure into FFL microstructure. The effect of heat treatment on microstructures and properties was studied. The results showed that the static recrystallization kinetics in (a+y) phase region took the form of Avrami equitation, and the remnant lamellae in DP microstructure were detrimental to room temperature tensile properties. The FL microstructures were obtained after heat treatment in phase region using DP microstructure, the uniform FFL microstructure was beneficial to comprehensive properties.展开更多
基金National High-Tech Projects(863 program)supported this research under the contract number 2001AA301080 and 2002AA305209 respectively.
文摘The heat treatment, including two steps, was proposed to obtain Fine Fully Lamellar (FFL) microstructure on TiAl containing minor Ni. The first step was in (a+y) phase region to get Duplex (DP) microstructure, and the second step was in a phase region transforming DP microstructure into FFL microstructure. The effect of heat treatment on microstructures and properties was studied. The results showed that the static recrystallization kinetics in (a+y) phase region took the form of Avrami equitation, and the remnant lamellae in DP microstructure were detrimental to room temperature tensile properties. The FL microstructures were obtained after heat treatment in phase region using DP microstructure, the uniform FFL microstructure was beneficial to comprehensive properties.