Solidification microstructure characteristics of Ti–44Al–4Nb– 2Cr–0.1B alloy under various cooling rates during mushy zone
Solidification microstructure characteristics of Ti–44Al–4Nb– 2Cr–0.1B alloy under various cooling rates during mushy zone
复制标题
Ti～44Al～4Nb～2Cr～0.1B合金在不同冷却速率下糊状区凝固组织特征
DOI：
10.1007/s12598-015-0633-z
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发表时间：
2015
期刊：
影响因子：
8.8
通讯作者：
Jinshan Li.
中科院分区：
文献类型：
--
作者：
Peng Han;Hongchao Kou;Jieren Yang;Guang Yang;Jinshan Li.
β凝固TiAl合金作为铸造合金在航空工业领域具有巨大的潜力。在本工作中，研究了糊状区冷却速率对Ti-44Al-4Nb-2Cr-0.1B合金凝固行为的影响。采用真空感应加热装置，结合温度控制系统。将过热凝固的Ti-44Al-4Nb-2Cr-0.1B合金熔化成b相，冷却速率分别为10、50、100、200、400和700 K/min-1。结果表明，随着冷却速率从10增加到700 K/min-1，a2/c片层的团落尺寸从1513 lm减小到48 lm，凝固偏析显着减少。随着冷却速率的增加，a2/γ片状团中残余B2相的含量也随之减少。此外，合金在局部枝晶间区域会以亚包晶的方式凝固，这可归因于凝固过程中Al元素的溶质重新分布和富集。
Beta-solidifying TiAl alloy has great potential in the field of aero-industry as a cast alloy. In the present work, the influence of cooling rate during mushy zone on solidification behavior of Ti–44Al–4Nb–2Cr–0.1B alloy was investigated. A vacuum induction heating device.combining with temperature control system was used. The Ti–44Al–4Nb–2Cr–0.1B alloy solidified from superheated was melted to b phase with the cooling rates of 10, 50, 100, 200, 400 and 700 K/min-1, respectively. Results show that with the increase in cooling rate from 10 to 700 K/min-1, the colony size of a2/c lamella decreases from 1513 to 48 lm and the solidification segregation significantly decreases. Also the content of residual B2 phase within a2/γ lamellar colony decreases with the increase in cooling rate..In addition, the alloy in local interdendritic regions would solidify in a hypo-peritectic way, which can be attributed to the solute redistribution and enrichment of Al element in solidification.