Abstract The fatigue crack propagation (FCP) behavior of Inconel 718 alloy manufactured by laser powder bed fusion (L-PBF) was studied at 25 and 650 °C, and compared to those of conventionally processed counterpart. The FCP rates of L-PBF Inconel 718 alloy were found to be significantly higher than those of conventionally processed counterpart at 25 °C in low and intermediate ΔK regimes. The FCP rates decreased in near-threshold ΔK regime at 650 °C, while the reversal occurred above ΔK of 7 MPa√m, as compared to those at 25 °C. The FCP behavior of L-PBF Inconel 718 alloy was discussed based on micrographic and fractographic analyses.

中文翻译：

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激光粉末床熔融法制备Inconel 718合金的室温和高温疲劳裂纹扩展行为

摘要 研究了激光粉末床熔化 (L-PBF) 制造的 Inconel 718 合金在 25 和 650 °C 下的疲劳裂纹扩展 (FCP) 行为，并与常规加工的对应物进行了比较。发现 L-PBF Inconel 718 合金的 FCP 率在 25 °C 下在低和中 ΔK 范围内显着高于常规加工对应物的 FCP 率。FCP 速率在 650°C 时在接近阈值 ΔK 范围内下降，而与 25°C 时相比，在 ΔK 大于 7 MPa√m 时发生逆转。基于显微和断口分析讨论了 L-PBF Inconel 718 合金的 FCP 行为。