选区激光熔化制造Inconel 718合金的氢脆行为  

Hydrogen embrittlement behavior of Inconel 718 alloy prepared by selective laser melting

作　　者：曾强 吴颖 夏林 朱绍维 ZENG Qiang;WU Ying;XIA Lin;ZHU Shao-wei(School of Intelligent Manufacturing,Sichuan University of Arts and Science,Dazhou 635000,China;Chengdu Aircraft Industrial(Group)Co Ltd,Chengdu 610092,China)

机构地区：[1]四川文理学院智能制造学院,四川达州635000 [2]成都飞机工业(集团)有限责任公司,四川成都610092

出　　处：《材料热处理学报》2024年第10期88-94,共7页Transactions of Materials and Heat Treatment

基　　金：达州市智能制造产业技术研究院2022年度开放基金项目(ZNZZ2214)。

摘　　要：后热处理可以有效改善选区激光熔化(SLM)制造的Inconel 718合金的强塑性匹配,但其氢脆断裂行为目前还尚不明确。为此,对SLM制造的Inconel 718合金进行了高温固溶+单级时效热处理,并采用扫描电镜的电子背散射衍射(EBSD)和背散射电子(BSE)成像对其显微组织进行了分析,通过预充氢前后的拉伸实验对合金的氢脆敏感性进行了评估,并采用EBSD和BSE对拉伸试样的断口表面形貌和裂纹扩展路径进行了分析。结果表明:热处理后,SLM制造的Inconel 718合金的抗拉强度可达1341 MPa,并保持24.5%的断后伸长率,但也具有较高的氢脆敏感性,充氢96 h后合金的强度损伤和塑性损失分别达到18.5%和52.3%。拉伸过程中晶界上由于δ相以及滑移带引起的应力集中促进了晶界上氢的局部富集,从而诱发沿晶氢脆裂纹的萌生及扩展。Post-heat treatment can effectively improve the strength plasticity matching of Inconel 718 alloy prepared by selective laser melting(SLM),but its hydrogen embrittlement(HE)fracture behavior is still unclear.For this purpose,the Inconel 718 alloy prepared by SLM was subjected to high-temperature solution+single-stage aging treatment,and its microstructure was analyzed using electron backscatter diffraction(EBSD)and backscatter electron microscopy(BSE)imaging under scanning electron microscopy.The hydrogen embrittlement sensitivity of the alloy was evaluated by tensile experiments before and after hydrogen pre-charging,and the fracture surface morphology and crack propagation path of the tensile samples were analyzed using EBSD and BSE.The results show that after heat treatment,the tensile strength of the Inconel 718 alloy prepared by SLM can reach 1341 MPa,and the elongation is 24.5%,but it also has high hydrogen embrittlement sensitivity.After 96 h of hydrogen charging,the strength and plastic loss of the alloy reach 18.5%and 52.3%,respectively.The stress concentration caused by theδphase and slip bands at the grain boundaries during the tensile process promotes the local enrichment of hydrogen at the grain boundaries,thereby inducing the initiation and propagation of intergranular hydrogen embrittlement cracks.

关 键 词：Inconel 718合金 选区激光熔化 氢脆 裂纹扩展路径 

分 类 号：TG132.3[一般工业技术—材料科学与工程]