高钼含量β型钛合金的偏析行为及预防措施

摘要

The radiographic test, OM, SEM and EDS were adopted to study the segregation behavior of theβtitanium alloy which possesses high molybdenum content. The results show that, the black spots in the ingot and rolling bar from 1/2 radius to the central regions are α flecks. The EDS results shows that the α flecks are lack of Mo element. The standard microstructure of the rolling bar after solution heat treatment is singleβphase. A lot of unchanged fineαphase particles gather in the grey black segregation zone, so, the spot shows grey black under low magnification inspection.%采用 X 射线透射成像仪(XRT)、光学显微镜(OM)、扫描电镜(SEM)和能谱分析(EDS)等手段对某高钼含量β型钛合金的偏析行为进行研究。结果表明：合金铸锭及其轧制棒材1/2半径至中心区域在X射线透射检测及低倍检查时发现的灰黑色偏析斑点为α斑点；能谱分析(EDS)显示，该灰黑色偏析斑点为 Mo 元素贫化区域；在光学显微镜下观察固溶处理后的棒材，其正常区域组织为单相β晶粒，而灰黑色偏析斑点区域聚集着大量未转变的细小α相颗粒，其在低倍观察时呈现灰黑色。