中文摘要：

利用光学显微镜和扫描电镜，研究热处理对铸态Ti-43AI-4Nb-1．4W-0．6B-0．1Y合金及其在1200℃锻造后的组织中β（B2）相偏析的影响。结果表明：在a＋7两相区保温适当时间，可减少铸态合金组织中的β（B2）相偏析，经1250℃／6h＋AC（aircooling）热处理后，晶界处和片层内的β（B2）相偏析明显减少，但不能消除β（B2）相；经过热变形后，β（B2）相发生变形甚至被破碎，有利于β（B2）相在随后的热处理中消除；热处理后，合金中β（B2）相的含量与变形中的动态再结晶密切相关，高应变速率下β（B2）相动态再结晶不完全，在随后的热处理过程中，由于变形储能的作用更易消除β（B2）相。

英文摘要：

The effect of heat treatment on the elimination of β（B2） phase segregating in as-cast Ti-43A1-4Nb-1.4W-0.6B- 0.1Y alloy was systematically investigated by optical microscopy and scanning electron microscopy. The results of the experiments indicate that β phase segregation can be reduced by holding appropriate time in two phase region of a＋y. The ,8（B2） segregation at the grain boundaries and in lamellar colonies can be efficiently reduced by 1 250 ℃/6 h＋ AC（air cooling） for the alloy samples, but can＇t be eliminated; the fl phase will be deformed or even be broken after hot deformmation which is beneficial to subsequent heat treatment process; the volume fraction and deformation of β（B2） after heat treatment is closely related to the dynamic recrystallization. When deformed at high strain rate, β（B2） phase dynamic recrystaUization is incompletely, and the β（B2） phase is easier to be eliminated owing to deformation energy in subsequent heat treatment process.