(中國(guó)科學(xué)院金屬研究所, 沈陽110015)
摘 要: Ti-55高溫鈦合金在緩冷(1000 kg鑄錠冒口)條件下，正常凝固區(qū)中稀土相呈彌散分布狀態(tài)，初始補(bǔ)縮區(qū)中稀土相聚集成團(tuán)，正常補(bǔ)縮區(qū)中稀土相顆粒沿平行于凝固界面方向規(guī)則排列；在快冷(錘砧薄片)條件下， 稀土相除彌散分布在合金中外，出現(xiàn)稀土相顆粒排列成行的現(xiàn)象。兩種凝固條件下均出現(xiàn)顆粒規(guī)則排列現(xiàn)象的原因是凝固界面的平面長(zhǎng)大。
關(guān)鍵字: Ti-55高溫鈦合金；稀土相；凝固特征
（Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110015, P.R.China）
Abstract:The solidifies characterization of rare earth-rich phase in slowly and rapidly cooled Ti-55 alloy was observed and analyzed. After the ingot of Ti-55 alloy solidifies slowly, the rare earth-rich phase particles are uniformly distributed in the coarse dendritical matrix within normal solidification zone. However, for the shrinkage area, lots of aggregated particles appear in the initial shrinkage zone, in addition, the particles in the normal shrinkage zone formed bands and are aligned parallel to the advancing solidification front. Rapid solidification produces fine rare earth-rich phase particles, of which some particles are uniformly distributed in the α-Ti matrix, others are lined up to be rows of band. The reason for the formation of the band both in the ingot-riser area and in the rapid solidification flakes is that the advancing liquid-solid interface remains planar.
Key words: Ti-55 high temperature titanium alloy; rare earth-rich phase; solidified characterization
