Effects of Al content on microstructures and high-temperature tensile properties of two newly designed CoNi-base superalloys
Effects of Al content on microstructures and high-temperature tensile properties of two newly designed CoNi-base superalloys
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Al含量对两种新设计的CoNi基高温合金显微组织和高温拉伸性能的影响
DOI：
10.1016/j.jallcom.2020.155337
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发表时间：
2020-09
影响因子：
6.2
通讯作者：
Sun Xiaofeng
中科院分区：
文献类型：
--
作者：
Wen Mingyue;Sun Yuan;Yu Jinjiang;Yang Yanhong;Zhou Yizhou;Sun Xiaofeng
与无镍钴基高温合金相比，镍基高温合金具有更宽的γ/γ′畴和更高的γ′溶剂温度，近年来引起了广泛的研究兴趣。在本研究中，制备了两种Al含量为9at的镍基高温合金。%或13%。%采用CALPHAD方法进行设计。9Al合金在凝固态和时效态表现为γ/γ′双相组织，而13Al合金在晶界上析出β-(Co,Ni)Al相。凝固态9Al和13Al的γ′-溶剂分别为1238℃和1220℃，时效态9Al和13Al中γ′的含量分别为64%和80%。900℃拉伸试验表明，Al含量对镍基高温合金的高温拉伸性能起着至关重要的作用。时效13Al合金屈服强度低于时效9Al合金，但拉伸应变较大，这是由于时效13Al合金中较软的γ′析出物形状不规则，β颗粒周围容易形成局部细小裂纹。这说明β颗粒的存在可以有效地缓解高温合金的晶界脆性。
CoNi-base superalloys have recently attracted intensive research interests due to their wider γ/γ′ domains and higher γ′ solvus temperatures compared to Ni-free Co-base superalloys. In this work, two CoNi-base superalloys with Al content of 9 at.% or 13 at.% were designed with the aid of CALPHAD approach. The 9Al alloy exhibits a γ/γ′ dual-phase microstructure in its as-solidified and aged states, but the β-(Co,Ni)Al phase precipitates on the grain boundaries in the 13Al alloy. The measuredTγ′-solvusof the as-solidified 9Al and 13Al is 1238 °C and 1220 °C, respectively, and the fraction of γ′ in the aged 9Al and 13Al is 64% and 80%, respectively. Tension tests at 900 °C reveal that the Al content plays a vital role on high-temperature tensile properties of the current CoNi-base superalloys. The lower yield strength but a larger tensile strain of the aged 13Al alloy, as compared with the aged 9Al alloy, are attributed to irregular shape of the softer γ′ precipitates and the easy formation of the local tiny cracks around the β particles. This implies that the existence of β particles can effectively relieve the grain-boundary brittleness of superalloys at high temperature.
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DOI：
10.1016/j.cossms.2019.100784
发表时间：
2019-12
影响因子：
11
作者：
Fei Zhou;Yang Zhou;Jun Wang;Jiamiao Liang;Gao Haiyan;M. Kang
通讯作者：
Fei Zhou;Yang Zhou;Jun Wang;Jiamiao Liang;Gao Haiyan;M. Kang
DOI：
--
发表时间：
2015
期刊：
--
影响因子：
--
作者：
S. Makineni;B. Nithin;K. Chattopadhyay
通讯作者：
S. Makineni;B. Nithin;K. Chattopadhyay
影响因子：
4.4
作者：
H.-Y. Yan;V. Vorontsov;D. Dye
通讯作者：
H.-Y. Yan;V. Vorontsov;D. Dye
影响因子：
1.4
作者：
Jun Zhu;M. Titus;T. Pollock
通讯作者：
Jun Zhu;M. Titus;T. Pollock
含 γ-γ-Co 基高温合金中 Zr 或 Hf 的 Laves 相的识别
影响因子：
6.2
作者：
Li Wang;Lin Song;Andreas Stark;Yong Liu;Michael Oehring;Uwe Lorenz;Florian Pyczak
通讯作者：
Florian Pyczak