A comparison of the microstructures and mechanical properties of a GH648 superalloy fabricated by selective laser melting and casting
A comparison of the microstructures and mechanical properties of a GH648 superalloy fabricated by selective laser melting and casting
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DOI：
10.1016/j.msea.2021.141178
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发表时间：
2021-04-03
期刊：
影响因子：
6.4
通讯作者：
Song, Min
中科院分区：
文献类型：
--
作者：
Cheng, Bowen;Liu, Chaoqiang;Song, Min
对通过选区激光熔化（SLM）或铸造，然后进行固溶时效（SA）热处理制造的高铬GH648高温合金的显微组织和机械性能进行了系统研究。 SLMed-SA 样品的平均晶粒尺寸为 63.8 µm，远小于铸造 SA 样品的晶粒尺寸。铸造-SA 和 SLMed-SA GH648 高温合金具有相似的相组成，包括 α-Cr 初生相、针状 α-Cr 析出物和碳化物，不同之处在于 β-Cr 相不同。在 SLMed-SA 合金中可以明显地检测到相，而不是在铸造-SA 合金中。 SLMedSA 合金中这些相的尺寸比铸造 SA 合金中的相要细得多。拉伸试验表明，SLMed-SA 样品的碳化物、β-Cr 析出物和晶粒尺寸较小，且析出物数量较多，因此 SLMed-SA 样品比铸造 SA 样品具有更高的强度。
The microstructures and mechanical properties of a high-Cr contained GH648 superalloy, manufactured by selective laser melting (SLM) or casting, and then experiencing solution and ageing (SA) heat treatments, were investigated systematically. The SLMed-SA samples have an average grain size of 63.8 ?m, which is far finer than that of the casting-SA samples. The casting-SA and SLMed-SA GH648 superalloys have a similar phase constitution, including ?-Cr primary phase, acicular ?-Cr precipitates, and carbides, except that the ?? phase can be obviously detected in the SLMed-SA alloy, instead of the casting-SA alloy. The sizes of these phases in the SLMedSA alloy are much finer than those in the casting-SA alloy. Tensile tests indicate that the SLMed-SA samples have much higher strength than the casting-SA samples, due to the smaller size in the carbides, ?-Cr precipitates and grain, and the increased number of the precipitates in the SLMed-SA samples.