650℃/500 MPa应力时效对GH4169合金板材组织及室温拉伸性能的影响  

Effect of 650℃/500 MPa stress aging on microstructure and room temperature tensile properties of GH4169 alloy plate

作　　者：刘砚飞 丁承尧 贺进 钟燕 田伟 余心宏[2] 王建国[2] LIU Yan-fei;DING Cheng-yao;HE Jin;ZHONG Yan;TIAN Wei;YU Xin-hong;WANG Jian-guo(AECC Sichuan Gas Turbine Establishment,Chengdu 610500,China;School of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]中国航发四川燃气涡轮研究院,四川成都610500 [2]西北工业大学材料学院,陕西西安710072

出　　处：《材料热处理学报》2024年第5期87-93,共7页Transactions of Materials and Heat Treatment

摘　　要：对固溶+时效处理的GH4169合金板材分别进行了不同时间的应力时效和无应力时效处理,采用光学显微镜(OM)、扫描电镜(SEM)和电子万能试验机等分析了不同应力时效处理后合金的显微组织和室温拉伸性能。结果表明:应力对GH4169合金板材的显微组织无明显影响,经过应力时效和无应力时效处理后γ″相仅发生略微粗化,尺寸由19.02 nm增长至23 nm左右,仍为圆形颗粒状形貌。无应力时效处理对板材的室温拉伸性能基本无影响,这是由于GH4169合金板材的室温变形机制为位错做剪切γ″相运动,板材经无应力时效处理后γ″相的尺寸与经固溶+时效处理的γ″相的尺寸相当,位错剪切γ″所需的应力相当使得室温拉伸性能未变化。随应力时效时间的增加,板材的室温拉伸强度逐渐降低,室温拉伸塑性逐渐增加,这是由于应力时效过程中板材已发生残余塑性变形,位错已切入γ″相,后续室温拉伸过程中,位错再次剪切γ″相所需的应力减小进而导致板材室温拉伸强度降低,拉伸塑性增加。GH4169 alloy plate treated with solution and aging were subjected to stress aging and stress free aging treatments for different time.Microstructure and room temperature tensile properties of the alloy after different stress aging treatments were analyzed using optical microscope(OM),scanning electron microscopy(SEM)and electronic universal testing machine.The results show that stress has no significant effect on the microstructure of the GH4169 alloy plate.After stress aging and stress free aging treatment,only a slight coarsening of γ″phase occurs,and the size increases from 19.02 nm to about 23 nm,still exhibiting a circular granular morphology.The stress free aging treatment has little effect on the room temperature tensile properties of the GH4169 alloy plate.This is because the room temperature deformation mechanism of the GH4169 alloy plate is the shear γ″-phase movement of dislocations,the size of γ″phase after stress free aging treatment is equivalent to that of γ″phase after solution+aging treatment,and the stress required for dislocation shear γ″phase is equivalent,resulting in no change in room temperature tensile properties.As the stress aging time increases,the room temperature tensile strength of the alloy plate gradually decreases,and the room temperature tensile plasticity gradually increases.This is because during the stress aging process,the alloy plate has undergone residual plastic deformation,and dislocations have entered the γ″phase.In the subsequent room temperature tensile process,the stress required for dislocations again to shear the γ″phase decreases,leading to a decrease in room temperature tensile strength and an increase in tensile plasticity of the alloy plate.

关 键 词：GH4169合金板材 应力时效 显微组织 室温拉伸性能 

分 类 号：TG132.3[一般工业技术—材料科学与工程]