F. Tang et al., Effect of boron microalloying on microstructure, tensile properties and creep behavior of Ti-22Al-20Nb-2W alloy, MAT SCI E A, 315(1-2), 2001, pp. 147-152
The effect of 0.2 at.% boron addition on the microstructure, tensile proper
ties, and creep behavior of Ti-22Al-20Nb-2W were investigated. A TiB phase
was observed in the B-doped alloy, which shows that the solubility of boron
in this alloy is very low. The addition of 0.2 at.% boron was very effecti
ve in reducing the prior beta -grain size of the Ti-22Al-20Nb-2W alloy, whi
ch is thought to be due to a strong boron segregation at the grain boundari
es. The decrease in grain size due to the addition of boron is effective in
improving the alloy's room temperature ductility. The addition of a small
amount of boron was beneficial in lowering the steady-state creep rate at 6
50 degreesC/310 MPa, but did not improve the creep behavior at 750 degreesC
/310 MPa. (C) 2001 Elsevier Science B.V. All rights reserved.