钛铝含量对IN718合金激光增材试样组织性能的影响  

Effect of Ti+Al Content on the Microstructure and Properties of Laser Additive Specimens of IN718 Alloy

作　　者：雷远涛 伍文星 阳彤 申龙章 陈勇[1] 朱红梅 邱长军[1] LEI Yuan-tao;WU Wen-xing;YANG Tong;SHEN Long-zhang;CHEN Yong;ZHU Hong-mei;QIU Chang-jun(Hunan Provincial Key Laboratory of Equipment Safety Service Technology under Abnormal Environment,University of South China,Hengyang 421001,China)

机构地区：[1]南华大学超常环境下装备安全服役技术湖南省重点实验室,湖南衡阳421001

出　　处：《稀有金属与硬质合金》2024年第2期55-62,共8页Rare Metals and Cemented Carbides

基　　金：国防科技重点实验室基金项目(JCKY61420052002);中央军委装备发展部装备预研基金项目(61400040204);国家重点研发计划(2017YFE0301300);湖南省研究生科研创新项目(223YSC009)。

摘　　要：为提升激光增材IN718合金部件的力学性能和服役温度,按梯度增加Ti+Al含量制备了五种改进型IN718激光增材样品,采用万能实验机、SEM、XRD和JMatpro软件等研究了样品的常温和高温力学性能及组织结构。结果表明,随着Ti+Al含量的增加,γ′相占比逐渐上升,样品室温强度增大而延伸率明显下降。当Ti+Al含量增加到7.6%时,样品中的γ′析出相占比是γ相的5倍,硬度为55.6 HRC,因脆性相的大量析出导致裂纹萌生;经1 100℃×1 h+850℃×8 h热处理后的样品在850℃时的强度随Ti+Al含量的增加先升高后降低,Ti+Al含量为5.6%时其高温屈服强度和延伸率达到最大值,分别为553 MPa和12%,且各向同性,此时γ′析出相和γ相占比接近,分别为41.5%和39.9%。在后续研究中,可将标准IN718合金中的Ti+Al含量提高到5.6%,恰当利用γ′强化获得优良的高温力学性能和激光增材工艺相容性。To improve the mechanical properties and service temperature of laser additive IN718 alloy components,five improved IN718 laser additive samples with the gradient increase in Ti+Al content were prepared.The mechanical properties at room temperature and high temperature and microstructure of the samples were studied by universal testing machine,SEM,XRD,and JMatpro software.The results indicate that as the Ti+Al content increases,the proportiaon ofγ′phase gradually rises,with an increase in room temperature strength and a significant decrease in elongation.When the content of Ti+Al reaches 7.6%,the proportion ofγ′precipitated phase is 5 times that ofγphase and the hardness is 55.6 HRC.Then the abundant precipitation of brittle phases results in the initiation of cracks.After undergoing 1100℃×1 h+850℃×8 h heat treatment,the high-temperature strength of the samples at 850℃initially increases and then decreases with the increasing Ti+Al content.And when the content of Ti+Al arrives at 5.6%,the high-temperature yield strength and elongation of the samples reach the maximum value of 553 MPa and 12%,respectively,showing consistency in all directions.Meanwhile,the proportions ofγ′precipitated phase andγphase are close(41.5%and 39.9%,respectively).In subsequent research,the Ti+Al content in standard IN718 alloy can be increased to 5.6%,and properly usingγ′strengthening can obtain excellent high-temperature mechanical properties and compatibility of laser additive process.

关 键 词：激光增材制造 IN718合金 Ti+Al含量 力学性能 析出相 

分 类 号：TH142.2[一般工业技术—材料科学与工程]