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固溶处理对选区激光熔化Inconel718合金组织与硬度的影响∗

  • 郭宇豪

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

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  • ， 赵学平

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

    ×
  • ， 白朴存

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

    ×
  • ， 曹宇

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

    ×
  • ， 侯小虎

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

    ×
  • ， 刘飞

    机 构：

    内蒙古工业大学材料科学与工程学院 呼和浩特 010051

    ×

内蒙古工业大学材料科学与工程学院 呼和浩特 010051；

Effects of Solution Treatment on Microstructure and Hardness of Inconel 718 Alloy Fabricated by Selective Laser Melting

  • GUO Yuhao

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

    ×
  • ， ZHAO Xueping

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

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  • ， BAI Pucun

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

    ×
  • ， CAO Yu

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

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  • ， HOU Xiaohu

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

    ×
  • ， LIU Fei

    Affiliation：

    College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China

    ×

College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051 , China；

作者简介:

白朴存(通信作者),男,1967年出生,博士,教授。主要研究方向为轻质材料。E-mail:pcbai@imut.edu.cn

中图分类号:TG132;TG156

文献标识码:A

DOI:10.11933/j.issn.1007-9289.20210127001

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目录contents

    摘要

    利用选区激光熔化技术制备 Inconel 718 合金,对其在不同温度、时间和冷却条件下进行热处理。 采用扫描电子显微镜、 电子背散射衍射仪和显微硬度计研究不同热处理工艺条件下 Inconel 718 合金的微观组织与硬度。 结果表明:当热处理温度为 1080 ℃时,沉积态合金中的束状亚结构消失、第二相含量减少,随着保温时间的延长,晶粒开始由非均匀柱状晶转变为再结晶晶粒,残余应力集中区和小角度晶界逐渐减少,并且形成60°退火孪晶,硬度从 292 HV 降低至 253 HV;当热处理温度为 1130 ℃时,沉积态合金中的非平衡组织全部发生再结晶,残余应力集中区基本消失,晶粒内部出现均匀的退火孪晶,硬度保持在 220 HV 左右;对于 1080 ℃ / 60 min 热处理试样,随炉冷却方式的硬度高达 431 HV,其较高的硬度主要与随炉冷却形成大量的亚结构和析出相有关。

    Abstract

    Inconel 718 alloy was prepared by selective laser melting technique and then processed under different temperature, time and cooling conditions. The microstructure and hardness of Inconel 718 alloy under different heat treatment conditions were investigated by scanning electron microscope, electron backscattering diffractometer and microhardness tester. The results show that when the heat treatment temperature is 1080 ℃ , the bundle substructure in the deposited alloy disappears and the content of the second phase decreases. With the increase of the heat treatment time, the grains start to change from non-uniform columnar grains to recrystallized grains, the residual stress concentration areas and small-angle grain boundaries gradually decrease, and 60° annealing twins are formed, the hardness decreases from 292 HV to 253 HV. When the heat treatment temperature is 1130 ℃ , all the non-equilibrium structures in the deposited alloy recrystallize, the residual stress concentration area almost disappears, the uniform annealing twins appeared in the grains, and the hardness remained at about 220 HV. The hardness of sample heat treated at 1080 ℃ / 60 min is as high as 431 HV, and the higher hardness is mainly related to the formation of a large number of substructures and precipitates with furnace cooling.

  • 0 前言

  • Inconel718合金是一种时效强化型镍基高温合金,具有抗辐射、抗氧化、高温力学性能和热加工性能优异等特点,目前已在航空发动机中得到广泛应用[1-3]。 Inconel718合金中的强化相主要有 γ′相(Ni3AlTi)、γ″相(Ni3Nb)和 δ 相(Ni3Nb),γ′相为辅助强化相,γ″相为主要强化相,δ 相是由亚稳态 γ″相在高温(650℃以上)下长时间转变而成的一种稳定相[4-8]。除强化相之外,Inconel718合金中还容易出现Laves相((NiCrFe)2NbMoTi),Laves相是由于成型工艺引起元素偏析而形成的,Laves相形成过程中会消耗大量的强化元素Nb。研究表明,Laves相较脆,服役过程中容易萌生裂纹,是Inconel718合金失效的主要原因[9-10]。

  • 航空领域涉及的一些Inconel718合金制件除性能要求较高之外,其结构也极为复杂,传统制造工艺已不能满足高性能复杂构件的成形需求。激光增材制造技术是一种以数字模型为基础,将材料逐层堆积成形的制造技术[11-12]。与传统成形工艺相比, 激光增材制造技术具有加工工艺便捷、无须模具、冷却速率快和易于成形复杂构件的优点,目前该技术在航空发动机制造领域已得到应用[13-14]。由于激光增材制造技术具有快冷的特点,Inconel718合金在成形过程中会抑制强化相的析出,其组织主要为过饱和 γ 基体和枝晶间 γ+Laves共晶[15-16],为提升Inconel718合金的力学性能,需要通过后期热处理来改善其组织并消除Laves相。

  • 激光增材制造与铸造或锻造Inconel718合金的组织明显不同,因此不能完全按照铸件或锻件的热处理制度对其进行固溶处理。张杰等[17] 研究了不同固溶温度((940~1 250℃)/1h/WC) 下激光增材制造Inconel718合金的组织和性能演变规律,结果显示,在固溶温度为1 080℃ 时,沉积态试样中的非平衡组织已完全再结晶,硬度随固溶温度的升高而降低;牛雯[18] 参照锻件和铸件的热处理制度对选区激光熔化Inconel718合金试样进行固溶(980℃/1h)、均匀化( 1 080℃/1.5h) 和双级时效( 720℃/8h+620℃/8h) 热处理,经均匀化处理后,试样完全再结晶,Laves相也完全溶解到 γ 基体中;CAO等[19] 研究了固溶温度(( 930~1 230℃)/1h/WC) 对激光增材制造Inconel718合金组织和性能的影响,结果表明,固溶温度为1 080~1 130℃ 时,试样显微组织和硬度的变化最为明显, 硬度的变化主要与再结晶程度有关; KOURAYTEM等[20]重点研究了固溶处理对激光增材制造Inconel718合金力学性能各向异性的影响,研究表明,固溶处理过程中试样内部发生再结晶,沉积态试样中的柱状晶转变为等轴晶,并促使试样的各向异性降低。

  • 目前,激光增材制造Inconel718合金常用的固溶温度为1 080~1 130℃, 而关于1 080~1 130℃ 下保温不同时间以及采用不同冷却方式固溶处理的研究还比较少。本文利用扫描电子显微镜( Scanning electron microscope,SEM)、电子背散射衍射( Electron backscattered diffraction, EBSD)和显微硬度计表征了1 080℃ 与1 130℃ 下保温不同时间以及采用不同冷却方式固溶处理Inconel718合金的显微组织、晶粒分布、残余应力、退火孪晶和硬度,研究了固溶处理Inconel718合金的组织和硬度演变规律,为进一步完善及优化选区激光熔化Inconel718合金的热处理制度奠定基础。

  • 1 试验准备

  • 1.1 样品制备

  • 采用EOS M280激光金属粉末烧结设备制备Inconel718合金,激光功率为350W,光斑直径为0.2mm, 扫描速度为1m/s, 单层铺粉厚度为0.04mm,激光扫描路径为条带式扫描,层间转角为67°。沉积完成后将其从基板上切下, 并切割成10mm×10mm×5mm的试样,试样坐标及取样方式见图1。

  • 图1 试样沉积示意

  • Fig.1 Sample deposition schematic diagram

  • 1.2 热处理制度

  • 使用KSL-1400X高温试验箱对Inconel718合金试样进行固溶处理,升温速率为10℃/min,固溶温度、时间与冷却方式见表1。为使试样受热均匀, 将试样包埋在含有石英砂的坩埚中进行加热,保温结束后对其进行冷却。冷却方式分别为炉冷( Furnace cooling, FC)、空冷(Air cooling, AC) 和水冷(Water cooling, WC)。

  • 表1 热处理工艺参数

  • Table1 Heat treatment process parameters

  • 1.3 分析方法

  • 使用240~2000目砂纸对试样YZ面进行粗磨和精磨,最后进行机械抛光并腐蚀金相。金相腐蚀液配比为酒精 ∶盐酸 ∶氯化铜=20ml ∶20ml ∶1g,腐蚀时间为30s。使用QUANTA FEG 650场发射扫描电镜对腐蚀好的试样进行显微组织观察。采用浓度为10%的高氯酸酒精溶液在-25~-30℃下对EBSD试样进行电解抛光,电压为30V,电流为0.35A,时间为90s,使用Oxford NordlysMax电子背散射衍射仪进行EBSD分析,采用Channel5软件对采集的EBSD数据进行后处理,获得晶粒、残余应力和退火孪晶分布图。使用Gatan 691型氩离子减薄仪对透射电镜试样进行减薄,使用Talos F200X场发射透射电子显微镜对减薄后的试样进行微观结构观察。利用HXD-1000TM数字显微硬度计对试样进行硬度测试,压力为9.8N,载荷时间为15s,每个试样测试10个点,去掉最大和最小值取平均值。

  • 2 结果与讨论

  • 2.1 显微组织分析

  • 为研究固溶温度、时间和冷却方式对选区激光熔化Inconel718合金显微组织的影响,对沉积态及固溶处理制度分别为1 080℃/( 60min、75min、 90min)/AC、1 130℃/(15min、30min、60min)/AC和1 080℃/60min/(WC、FC)的试样进行SEM测试,图2为沉积态与固溶处理Inconel718合金的SEM照片。从图2a可以看出,沉积态试样中含有大量细小的束状亚结构组织,熔池线交错排布,熔池高度约为40 μm,与铺粉层厚度一致。由于选区激光熔化工艺具有较高的加热、冷却速率,沉积层在快速凝固过程中会形成大量的束状亚结构组织(见图2a中的插图)。对图2a中的亚结构进一步放大并做能谱(Energy dispersive spectrometer, EDS)线扫描分析,结果显示衬度较亮的区域富含Nb、Mo和C元素。 ZHANG等[21]和RAGHAVAN等[22]研究了选区激光熔化Inconel718合金的组织和性能,研究表明沉积态合金中的第二相主要为Laves相和微量碳化物。可见,沉积态Inconel718合金中出现的束状亚结构应该是含有Laves相和微量碳化物的熔池凝固结晶区。图2b~2d为1 080℃/(60min、75min、 90min)/AC试样的SEM照片,SEM照片显示沉积态试样经固溶处理后熔池线消失、晶界出现,束状亚结构的分布范围和第二相含量随着保温时间的增加而减少。图2e~2g为1 130℃/( 15min、30min、 60min)/AC试样的SEM照片,从图中可以看出,固溶温度升高后,沉积态试样中的束状亚结构在较短保温时间下即可消失。对比图2b、2h和2i可知, 1 080℃/60min/WC和1 080℃/60min/AC试样的显微组织无明显区别,而炉冷试样内部出现了较为明显的亚结构组织,其组成和结构有待进一步分析。

  • 图2 不同热处理试样的SEM照片

  • Fig.2 SEM images of different heat treated samples

  • 图3 给出炉冷试样的TEM明场像和对应区域的选区电子衍射照片(晶带轴为[001])。通过对图3b中的衍射斑点进行标定,发现 γ 基体中存在 γ′相和 γ″相。 γ′相的析出温度为593~816℃,γ″相的析出温度为595~870℃ [5,23],由于炉冷方式的降温速率较低(冷却速率约为2.5℃/min),在冷却过程中会促进 γ′和 γ″相的析出。 Inconel718合金属于时效强化型合金,炉冷过程中消耗强化元素会影响后续时效阶段强化相的析出,因此选区激光熔化Inconel718合金制件固溶处理更宜选择WC或AC方式进行冷却。

  • 图3 1 080℃/60min/FC热处理试样的TEM与SAED照片

  • Fig.3 TEM and SAED images of 1 080℃/60min/FC heat treated sample

  • 2.2 晶粒特征分析

  • 图4 为1 080℃/(60min、75min、90min)/AC和1 130℃/( 15min、30min、60min)/AC试样的EBSD取向成像形貌( Inverse pole figure, IPF) 图。其中,2°~10°的晶界为小角度晶界,在图中用细线表示;大于10°的晶界为大角度晶界,在图中用粗线表示;0°~2°的晶界是由于噪点或其他因素引起的, 在此不作统计。由IPF图可知,沉积态试样中的晶粒以柱状晶为主,并且沿着沉积方向生长(Z方向); 沉积态试样内部存在大量的小角度晶界,这些小角度晶界的形成主要与沉积层反复加热、冷却形成的高密度位错有关[24]。利用截线法对大角度晶粒的长度和宽度进行统计。由图4a可知,沉积态中晶粒的平均长度为17.8 μm,宽度为10.4 μm;同一个熔池在横向(X方向)包含多个晶粒,在纵向(Z方向) 大多数晶粒尺寸小于40 μm,部分晶粒同时贯穿2或3个熔池。试样成形过程中,高能激光束不仅会使铺粉层熔化,沉积层也会被重新加热并引起表层熔化,由于垂直于沉积方向的散热最快,晶粒会沿着沉积方向择优生长。沉积层在激光束的交替作用下,最终形成了非均匀柱状晶。由图4b~4d可知, 当试样在1 080℃/(60min、75min、90min)/AC条件下热处理时, 晶粒长度基本保持不变( 约为18 μm),宽度从11.0 μm逐渐增加至13.2 μm;当保温时间为60min时,晶粒内部仍存在大量的小角度晶界,随着保温时间的延长,柱状晶内部无畸变的晶核逐渐长大,并形成亚晶或再结晶晶粒,相近的亚晶界通过滑移的方式转移到临近的晶界或亚晶界上,通过扩散等方式使两个或多个亚晶合并成为一个再结晶晶粒[25-26]。图4e~4g表明, 当试样在1 130℃/(15min、30min、60min)/AC条件下热处理时,晶粒的宽度和长度基本都保持在18 μm,晶粒内部的小角度晶界完全消失,说明沉积态试样中的非平衡组织已完全再结晶,晶粒度基本不随保温时间变化。沉积态和1 080℃/60min固溶处理试样中的晶粒呈柱状晶,当保温时间延长后,柱状晶逐渐转变为等轴晶;当固溶温度为1 130℃ 时,沉积态合金中的柱状晶在较短时间(<15min)内即可转变为等轴晶。

  • 图4 不同热处理试样的取向成像图

  • Fig.4 IPF images of different heat treated samples

  • 2.3 残余应力与退火孪晶分布分析

  • 图5 为沉积态和固溶处理(1 080℃/(60min、 75min、 90min)/AC、 1 130℃/( 15min、 30min、 60min)/AC) Inconel718合金的局域取向差角(Kernel average misorientation, KAM) 图和退火孪晶分布图。 KAM图是利用晶粒内部某一点与其相邻点之间的取向差统计的,局域取向差角越大的部位残余应力越集中[27-29],图中绿色至红色的渐变区为残余应力集中区。红色晶界为<111>60°退火孪晶界。从图5a可以看出,局域取向差角小于1°的占比保持在78%左右,沉积态试样中的残余应力主要集中在相邻柱状晶的晶界处。图5b~5d显示, 1 080℃/60min固溶处理试样的残余应力分布状态与沉积态基本一致。随着保温时间的延长,局域取向差角小于1°的占比增加到90%左右,残余应力集中区在再结晶晶粒内部消失,再结晶晶粒周围的残余应力也有所下降。由此可见,试样在1 080℃ 固溶处理时,保温60min之前主要为回复阶段,在回复阶段试样内部的残余应力变化较小;随着保温时间的进一步延长,试样内部开始发生再结晶。再结晶的形核通常在能量较高的区域发生,相邻柱状晶的晶界处残余应力较大、能量较高,因此更容易诱发再结晶的形核与长大。当固溶温度升高至1 130℃ 后,保温时间对局域取向差角基本没有影响,其小于1°的占比保持在98%左右,内部的残余应力集中区基本消失。图6为不同热处理试样的晶界差角图。从图6和图5可以看出,小角度晶界逐渐减少,并且形成大量的<111>60°退火孪晶,其含量最高可达50%;<111>60°退火孪晶界主要出现在再结晶晶粒内部,其含量随着固溶温度和时间的增加而增加。 Inconel718合金中的 γ 基体为面心立方结构,其层错能较低,试样在热处理过程中,残余应力较大区域先发生再结晶的形核与长大,由于相邻柱状晶晶界处的残余应力较大、第二相含量较高,再结晶晶粒在长大过程中会受到第二相的阻碍而形成孪晶[30]。

  • 2.4 硬度分析

  • 为研究固溶处理工艺对选区激光熔化Inconel718合金性能的影响,测试了不同固溶工艺处理试样的硬度。图7为沉积态和固溶处理((1 080℃/(60min、75min、90min)/AC、1 130℃/( 15min、 30min、60min)/AC和1 080℃/60min/(WC、FC)) 试样的硬度变化图。从图7可以看出,当固溶温度为1 080℃时,随着保温时间的延长,硬度从292HV降低至253HV;当固溶温度升高至1 130℃时,硬度值保持在220HV左右,基本不随保温时间变化;对于1 080℃/60min/(WC、AC、FC)三种不同冷却方式的试样,冷却速率越快硬度越小,随炉冷却试样的硬度高达431HV。影响硬度的因素主要有析出相含量、晶粒度等。对于1 080℃/AC试样,当保温时间为60min时,试样内部的束状亚结构消失,因此硬度较沉积态有所下降,当保温时间为75min和90min时,试样内部发生再结晶,小角度晶界减少是硬度下降的主要原因;当固溶温度为1 130℃ 时,试样内部的小角度晶界基本消失,并且全部完成再结晶,晶粒尺寸基本不随保温时间变化,所以硬度值保持不变;对于1 080℃/60min/( WC、AC、FC) 三种不同冷却速率的试样,炉冷试样中形成的亚结构组织较多,此外,炉冷试样中还出现了一些强化相, 亚结构和析出相是炉冷试样硬度提升的主要原因。

  • 图5 不同热处理试样的残余应力和退火孪晶图

  • Fig.5 Residual stress and annealing twins images of different heat treated samples

  • 图6 不同热处理试样的晶界差角图

  • Fig.6 Grain boundaries angle diagram of different heat treated samples

  • 图7 不同热处理试样的硬度

  • Fig.7 Hardness of different heat treated samples

  • 4 结论

  • (1) 沉积态Inconel718合金中由于快速凝固形成大量细小的束状亚结构和第二相,经1 080℃ 固溶处理后,试样中的束状亚结构和第二相明显减少,进一步升高固溶温度(1 130℃)后,沉积态合金中的非平衡组织完全发生再结晶、束状亚结构消失。

  • (2) 沉积态Inconel718合金中的残余应力主要集中在相邻柱状晶的晶界处,试样在固溶处理时, 残余应力促进了再结晶的形核与长大,再结晶晶粒长大过程中受第二相的阻碍而在晶粒内部形成大量退火孪晶。

  • (3) Inconel718合金的硬度除与再结晶程度有关之外, 还与亚结构和析出相含量密切相关, 在1 080℃和1 130℃ 下保温不同时间固溶处理试样硬度的变化主要与再结晶程度有关,而在1 080℃ 采用不同冷却方式固溶处理试样硬度的变化主要是与慢冷形成的亚结构和析出相含量有关。

  • 参考文献

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    • [2] LIU Y C,ZHANG H J,GUO Q Y,et al.Microstructure evolution of Inconel 718 superalloy during hot working and its recent development tendency[J].Acta Metallurgica Sinica,2018,54(11):1653-1664.

    • [3] QI H.Review of INCONEL 718 Alloy:Its history,properties,processing and developing substitutes [J].Journal of Materials Engineering,2018(8):92-100.

    • [4] ZHANG J,ZHANG Q L,LI D,et al.Effect of δ aging treatment on microstructure and tensile properties of repaired Inconel 718 alloy using laser additive manufacturing[J].Chinese Journal of Lasers,2020,47(1):74-81.

    • [5] SUNDARARAMA M,MUKHOPADHYAY P,BANERJEE S.Some aspects of the precipitation of metastable intermetallic phases in INCONEL 718[J].Metallurgical Transactions A,1992,23(7):2015-2028.

    • [6] LI C M,TAN Y B,ZHAO F.Modification of flow stress curve and processing maps of inconel 718 superalloy[J].Chinese Journal of Rare Metals,2020,44(6):585-596.

    • [7] WANG Z M,GUAN K,GAO M,et al.The microstructure and mechanical properties of deposited-IN718 by selective laser melting [J].Journal of Alloys and Compounds,2012,513:518-523.

    • [8] WANG Y,LIN L,SHAO W Z,et al.Effect of solid-solution treatment on microstructure and performance of GH4169 superalloy[J].Transactions of Materials and Heat Treatment,2007,28(B08):176-179.

    • [9] SONG K,YU K,LIN X,et al.Microstructure and mechanical properties of heat treatment laser solid forming superalloy Inconel 718[J].Acta Metallurgica Sinica,2015,51(8):935-942.

    • [10] 汤鑫,曹腊梅,盖其东,等.K4169 合金整体导向环精铸技术及热处理工艺研究[J].宇航材料工艺,2007(6):82-87.TANG X,CAO L M,GAI Q D,et al.Investment casting technology and heat treatment process of K4169 superalloy integral nozzle ring[J].Aerospace Materials & Technology,2007(6):82-87.(in Chinese)

    • [11] TANJA T,JOHANNES S,RANINER V,et al.Microstructure and mechanical properties of selective laser melted Inconel 718 compared to forging and casting [J].Materials Letters,2016,164:428-431.

    • [12] WANG Y C,LEI L M,SHI L,et al.Scanning strategy dependent tensile properties of selective laser melted GH4169[J].Materials Science and Engineering A,2020,788:139616.

    • [13] YANG C,DONG Z H,CHI C T,et al.Microstructure and mechanical properties of 24CrNiMo alloy steel formed by selective laser melting [J].Chinese Journal of Lasers,2020,47(5):380-390.

    • [14] YIN Y,KANG P,XXIAO M Z,et al.Effect of heat treatment on microstructure and microhardness of CoCrW alloys processed by selective laser melting[J].Chinese Journal of Lasers,2019,46(10):105-112.

    • [15] 杨鑫,王婉琳,范亚卓,等.3D 打印金属零件后处理研究现状[J].功能材料,2020,51(5):5043-5052.YANG X,WANG W L,FAN Y Z,et al.Research status of post-processing of 3D printing metal parts[J].Journal of Functional Materials,2020,51(5):5043-5052.(in Chinese)

    • [16] 张雪峰,李怀学,胡全栋,等.热处理对激光选区熔化GH4169高温合金的组织与拉伸性能的影响[J].航空制造技术,2019,62(19):78-85.ZHANG X F,Li X H,HU Q D,et al.Effect of heat treatment on the microstructure and tensile properties of GH4169 superalloy fabricated by selective laser melting[J].Aeronautical Manufacturing Technology,2019,62(19):78-85.(in Chinese)

    • [17] ZHANG J,ZHANG Q L,CHEN Z J,et al.Effects of solution temperature on microstructure and properties of Inconel 718 alloy fabricatedvia laser additive manufacturing[J].Surface Technology,2019,48(2):47-53.

    • [18] 牛雯.热处理对选区激光熔化成形 Inconel 718 合金的组织和性能的影响[D].北京:北京工业大学,2016.NIU W.Effect of heat treatment on the microstructure and mechanical properties of selective laser melting manufactured Inconel 718 superalloy[D].Beijing:Beijing University of Technology,2016.(in Chinese)

    • [19] CAO Y,BAI PC,LIU F,et al.Effect of the solution temperature on the precipitates and grain evolution of IN718 fabricated by laser additive manufacturing [J].Materials(Basel,Switzerland),2020,13(2):340-340.

    • [20] KOURAYTEM N,VARGA J,AMIN-AHMADI B,et al.A recrystallization heat-treatment to reduce deformation anisotropy of additively manufactured Inconel 718 [J].Materials & Design,2021,198:109228.

    • [21] ZHANG D Y,NIU W,CAO X Y,et al.Effect of standard heat treatment on the microstructure and mechanical properties of selective laser melting manufactured Inconel 718 superalloy [J].Materials Science and Engineering:A,2015,644:32-40.

    • [22] RAGHAVAM S,ZHANG B C,WANG P,et al.Effect of different heat treatments on the microstructure and mechanical properties in selective laser melted INCONEL 718 alloy[J].Advanced Manufacturing Processes,2017,32(14):1588-1595.

    • [23] AZADIAN S,WEI L Y,RICHARD W.Delta phase precipitation in Inconel 718[J].Materials Characterization,2004,53(1):7-16.

    • [24] CHEN K,HUANG R Q,LI Y,et al.Rafting-enabled recovery avoids recrystallization in 3D-printing-repaired single-crystal superalloys[J].Advanced Materials,2020,32(12):e1907164.

    • [25] MAHAJAN S,PANDE C S,IMAM M A,et al.Formation of annealing twins in f.c.c.crystals[J].Acta Materialia,1997,45(6):2633-2638.

    • [26] ALONE A,CHATTERJEE R,ALANKAR A.A comparative study of the effect of random and preferred crystallographic orientations on dynamic recrystallization behavior using a cellular automata model[J].Materials Today Communications,2020,25:101200.

    • [27] FRIEDEL F,PAYTON E J,EGGELER G,et al.On the characterization of recrystallized fraction using electron backscatter diffraction:A direct comparison to local hardness in an IF steel using nanoindentation [J].Materials Science and Engineering:A,2010,527(29):7854-7864.

    • [28] MENG Y,REN Q,JU X H.Evaluation of dislocation density by local grain misorientation in deformed metals[J].Transactions of Materials and Heat Treatment,2016,35(11):122-128.

    • [29] LIU H,SHUI J,CAI T,et al.Microstructural evolution and hardness response in the laser beam welded joints of pure titanium during recrystallization and grain growth[J].Materials Characterization,2018,145:87-95.

    • [30] WANG W,BRISSET F,HELBERT A L,et al.Influence of stored energy on twin formation during primary recrystallization[J].Materials Science and Engineering:A,2014,589:112-118.

  • 基本信息

    中图分类号: TG132;TG156
    文献标识码: A
    DOI: 10.11933/j.issn.1007-9289.20210127001

    基金信息

    国家自然科学基金(11672140, 11762014)；
    内蒙古自治区科技重大专项(ZDZX2018031)；
    内蒙古自治区科技计划(201803005)资助项目；
    Supported by National Natural Science Foundation of China (11672140, 116762014)；
    Inner Mongolia Autonomous Region Science and Technology Major Special Projects (ZDZX2018031)；
    Inner Mongolia Science and Technology Plan (201803005).；

    引用信息

    稿件历史

    收稿日期: 2021-01-27

  • 参考文献

    • [1] ZHANG Y C,YANG L,CHEN T Y,et al.Investigation on the optimized heat treatment procedure for laser fabricated IN718 alloy[J].Optics and Laser Technology,2017,97:172-179.

    • [2] LIU Y C,ZHANG H J,GUO Q Y,et al.Microstructure evolution of Inconel 718 superalloy during hot working and its recent development tendency[J].Acta Metallurgica Sinica,2018,54(11):1653-1664.

    • [3] QI H.Review of INCONEL 718 Alloy:Its history,properties,processing and developing substitutes [J].Journal of Materials Engineering,2018(8):92-100.

    • [4] ZHANG J,ZHANG Q L,LI D,et al.Effect of δ aging treatment on microstructure and tensile properties of repaired Inconel 718 alloy using laser additive manufacturing[J].Chinese Journal of Lasers,2020,47(1):74-81.

    • [5] SUNDARARAMA M,MUKHOPADHYAY P,BANERJEE S.Some aspects of the precipitation of metastable intermetallic phases in INCONEL 718[J].Metallurgical Transactions A,1992,23(7):2015-2028.

    • [6] LI C M,TAN Y B,ZHAO F.Modification of flow stress curve and processing maps of inconel 718 superalloy[J].Chinese Journal of Rare Metals,2020,44(6):585-596.

    • [7] WANG Z M,GUAN K,GAO M,et al.The microstructure and mechanical properties of deposited-IN718 by selective laser melting [J].Journal of Alloys and Compounds,2012,513:518-523.

    • [8] WANG Y,LIN L,SHAO W Z,et al.Effect of solid-solution treatment on microstructure and performance of GH4169 superalloy[J].Transactions of Materials and Heat Treatment,2007,28(B08):176-179.

    • [9] SONG K,YU K,LIN X,et al.Microstructure and mechanical properties of heat treatment laser solid forming superalloy Inconel 718[J].Acta Metallurgica Sinica,2015,51(8):935-942.

    • [10] 汤鑫,曹腊梅,盖其东,等.K4169 合金整体导向环精铸技术及热处理工艺研究[J].宇航材料工艺,2007(6):82-87.TANG X,CAO L M,GAI Q D,et al.Investment casting technology and heat treatment process of K4169 superalloy integral nozzle ring[J].Aerospace Materials & Technology,2007(6):82-87.(in Chinese)

    • [11] TANJA T,JOHANNES S,RANINER V,et al.Microstructure and mechanical properties of selective laser melted Inconel 718 compared to forging and casting [J].Materials Letters,2016,164:428-431.

    • [12] WANG Y C,LEI L M,SHI L,et al.Scanning strategy dependent tensile properties of selective laser melted GH4169[J].Materials Science and Engineering A,2020,788:139616.

    • [13] YANG C,DONG Z H,CHI C T,et al.Microstructure and mechanical properties of 24CrNiMo alloy steel formed by selective laser melting [J].Chinese Journal of Lasers,2020,47(5):380-390.

    • [14] YIN Y,KANG P,XXIAO M Z,et al.Effect of heat treatment on microstructure and microhardness of CoCrW alloys processed by selective laser melting[J].Chinese Journal of Lasers,2019,46(10):105-112.

    • [15] 杨鑫,王婉琳,范亚卓,等.3D 打印金属零件后处理研究现状[J].功能材料,2020,51(5):5043-5052.YANG X,WANG W L,FAN Y Z,et al.Research status of post-processing of 3D printing metal parts[J].Journal of Functional Materials,2020,51(5):5043-5052.(in Chinese)

    • [16] 张雪峰,李怀学,胡全栋,等.热处理对激光选区熔化GH4169高温合金的组织与拉伸性能的影响[J].航空制造技术,2019,62(19):78-85.ZHANG X F,Li X H,HU Q D,et al.Effect of heat treatment on the microstructure and tensile properties of GH4169 superalloy fabricated by selective laser melting[J].Aeronautical Manufacturing Technology,2019,62(19):78-85.(in Chinese)

    • [17] ZHANG J,ZHANG Q L,CHEN Z J,et al.Effects of solution temperature on microstructure and properties of Inconel 718 alloy fabricatedvia laser additive manufacturing[J].Surface Technology,2019,48(2):47-53.

    • [18] 牛雯.热处理对选区激光熔化成形 Inconel 718 合金的组织和性能的影响[D].北京:北京工业大学,2016.NIU W.Effect of heat treatment on the microstructure and mechanical properties of selective laser melting manufactured Inconel 718 superalloy[D].Beijing:Beijing University of Technology,2016.(in Chinese)

    • [19] CAO Y,BAI PC,LIU F,et al.Effect of the solution temperature on the precipitates and grain evolution of IN718 fabricated by laser additive manufacturing [J].Materials(Basel,Switzerland),2020,13(2):340-340.

    • [20] KOURAYTEM N,VARGA J,AMIN-AHMADI B,et al.A recrystallization heat-treatment to reduce deformation anisotropy of additively manufactured Inconel 718 [J].Materials & Design,2021,198:109228.

    • [21] ZHANG D Y,NIU W,CAO X Y,et al.Effect of standard heat treatment on the microstructure and mechanical properties of selective laser melting manufactured Inconel 718 superalloy [J].Materials Science and Engineering:A,2015,644:32-40.

    • [22] RAGHAVAM S,ZHANG B C,WANG P,et al.Effect of different heat treatments on the microstructure and mechanical properties in selective laser melted INCONEL 718 alloy[J].Advanced Manufacturing Processes,2017,32(14):1588-1595.

    • [23] AZADIAN S,WEI L Y,RICHARD W.Delta phase precipitation in Inconel 718[J].Materials Characterization,2004,53(1):7-16.

    • [24] CHEN K,HUANG R Q,LI Y,et al.Rafting-enabled recovery avoids recrystallization in 3D-printing-repaired single-crystal superalloys[J].Advanced Materials,2020,32(12):e1907164.

    • [25] MAHAJAN S,PANDE C S,IMAM M A,et al.Formation of annealing twins in f.c.c.crystals[J].Acta Materialia,1997,45(6):2633-2638.

    • [26] ALONE A,CHATTERJEE R,ALANKAR A.A comparative study of the effect of random and preferred crystallographic orientations on dynamic recrystallization behavior using a cellular automata model[J].Materials Today Communications,2020,25:101200.

    • [27] FRIEDEL F,PAYTON E J,EGGELER G,et al.On the characterization of recrystallized fraction using electron backscatter diffraction:A direct comparison to local hardness in an IF steel using nanoindentation [J].Materials Science and Engineering:A,2010,527(29):7854-7864.

    • [28] MENG Y,REN Q,JU X H.Evaluation of dislocation density by local grain misorientation in deformed metals[J].Transactions of Materials and Heat Treatment,2016,35(11):122-128.

    • [29] LIU H,SHUI J,CAI T,et al.Microstructural evolution and hardness response in the laser beam welded joints of pure titanium during recrystallization and grain growth[J].Materials Characterization,2018,145:87-95.

    • [30] WANG W,BRISSET F,HELBERT A L,et al.Influence of stored energy on twin formation during primary recrystallization[J].Materials Science and Engineering:A,2014,589:112-118.

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