Abstract:The effects of 0.5~1.0 at.% W contents on the solidification microstructure and element distribution behavior in the βo,α2,γ phases of Ti-42Al-5Mn alloy (at.%, the same below) with low cost and good hotworkability were systematically studied. The results show that the refractory metal W in different positions of the alloy ingots prepared by one-step vacuum induction melting with CaO crucible is evenly distributed, and the O content is controlled in the range of 556 ~ 560 ppm. The solidification microstructure can be refined by W addition, and the lamellar structure size and content are generally decreased with the increase of W content. By analyzing the distribution behavior of alloying elements in different phases, it is found that the enrichment order of Al in different phases is as follows: γ＞α2＞βo, while those of Ti, Mn and W are all: βo＞α2＞γ. W addition cannot change the distribution behavior of Ti and Al, but will change the distribution behavior of Mn to a certain extent. The partitioning coefficients of W in α2 and βo phases are generally increased linearly with its content rised, and they meet kWα2/γ=1.4026CW(at.%)+0.4313, kWβo/γ=1.3290CW(at.%)+1.8745,respectively. In Ti-42Al-5Mn alloy, the enrichment tendency of W in βo phase is about 5.6 times that of Mn, and the enrichment tendency in phase α2 is about 7.5 times that of Mn.