【摘要】 通过 OM,TEM等对航空用近 α高温钛合金 Ti60 0试样蠕变前后的显微组织进行了观察研究 ,结果发现 :随着蠕变条件的不同 ,硅化物粒子 (Ti5Si3)和 α2 (Ti3Al)粒子有着不同程度的析出 ,而且合金的残留 β相及次生 α相也有相应的变化。在蠕变过程中 ,α2 粒子的析出阻碍位错移动 ,强化了合金基体。稀土氧化物粒子 (Y2 O3)在蠕变前后比较稳定 ,其形貌和大小没有多大变化 ,粒子平均直径为 0 .6μm左右 ,最大直径不超过 1 μm。还研究了 60 0～650℃之间的蠕变试样 ,通过 TEM观察得知 ,在 650℃ /1 50 MPa/1 0 0 h试验条件下 ,Ti60 0合金的组织形貌仍然没有大的改变。更多还原

【Abstract】 Microstructure of a near α Ti alloy Ti600 ,containing Y with nominal composition of Ti 6Al 2 8Sn 4Zr 0 5Mo 0 4Si 0 1Y (wt%), was researched A lot of experiments of creep was done OM and TEM observation were carried out The results show that the precipitation α 2 phase (Ti 3Al) and silicides(Ti 5Si 3) are produced after different creep test RE element Y play great role in this alloy Yttrium oxide would localize at the grain boundary and near the dislocation as the matrix and lattice is different, yttrium oxide particles is precipitated RE element Y addition can refine the as cast microstructure, The average diameter of yttrium oxide (Y 2O 3) is no more than 0 6 μm, the maximum diameter is less than 1 μm更多还原