Comparative Investigation of the Downward and Upward Directionally Solidified Single-Crystal Blades of Superalloy CMSX-4
Comparative Investigation of the Downward and Upward Directionally Solidified Single-Crystal Blades of Superalloy CMSX-4
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DOI：
10.1007/s11661-016-3415-9
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发表时间：
2016-03
期刊：
影响因子：
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通讯作者：
Fu Wang;D. Ma;S. Bogner;A. Bührig-Polaczek
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文献类型：
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作者：
Fu Wang;D. Ma;S. Bogner;A. Bührig-Polaczek
采用向下定向凝固（DWDS）工艺对镍基高温合金CMSX-4单晶叶片进行了定向凝固。与Bridgman工艺的结果相比，对该工艺的可能效益进行了比较评估。DWDS工艺表现出良好的能力，用于铸造单晶组件。该工艺的热梯度比Bridgman工艺的热梯度高约7倍。该工艺可减少铸造缺陷，细化组织，减小γ/γ′共晶池尺寸，细化γ′析出相，减轻显微偏析程度，减小微孔尺寸和体积分数，为单晶高温合金叶片的凝固提供了更多的优势。
Single-crystal blades of Ni-base superalloys CMSX-4 have been directionally solidified using the downward directional solidification (DWDS) process. The possible benefits of the process were comparatively evaluated with respect to the Bridgman process’ results. The DWDS process exhibits good capabilities for casting the single-crystal components. The thermal gradients of this process are approximately seven times higher than those of the Bridgman process. It provides more advantages for solidifying the single-crystal superalloy blades by reducing the casting defects, refining the microstructure, decreasing the size of theγ/γ′ eutectic pools, refining theγ′ precipitates, alleviating the degree of the microsegregation, and minimizing the size and volume fraction of the micropores.