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放电等离子烧结制备细晶AlN陶瓷

赵东亮, 何庆, 朱在稳, 尹海清, 秦明礼

赵东亮, 何庆, 朱在稳, 尹海清, 秦明礼. 放电等离子烧结制备细晶AlN陶瓷[J]. 粉末冶金技术, 2024, 42(1): 29-35. DOI: 10.19591/j.cnki.cn11-1974/tf.2023020012
引用本文: 赵东亮, 何庆, 朱在稳, 尹海清, 秦明礼. 放电等离子烧结制备细晶AlN陶瓷[J]. 粉末冶金技术, 2024, 42(1): 29-35. DOI: 10.19591/j.cnki.cn11-1974/tf.2023020012
ZHAO Dongliang, HE Qing, ZHU Zaiwen, YIN Haiqing, QIN Mingli. Preparation of nanocrystalline AlN ceramics by spark plasma sintering[J]. Powder Metallurgy Technology, 2024, 42(1): 29-35. DOI: 10.19591/j.cnki.cn11-1974/tf.2023020012
Citation: ZHAO Dongliang, HE Qing, ZHU Zaiwen, YIN Haiqing, QIN Mingli. Preparation of nanocrystalline AlN ceramics by spark plasma sintering[J]. Powder Metallurgy Technology, 2024, 42(1): 29-35. DOI: 10.19591/j.cnki.cn11-1974/tf.2023020012

放电等离子烧结制备细晶AlN陶瓷

基金项目: 河北省省级科技计划资助项目(20311001D)
详细信息
    通讯作者:

    赵东亮: Email: dongliang.zhao@sinopack.cc

  • 中图分类号: TF123; O659.2

Preparation of nanocrystalline AlN ceramics by spark plasma sintering

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  • 摘要:

    采用纯纳米AlN粉和掺杂质量分数3%Y2O3的纳米AlN粉为原料,经放电等离子烧结工艺制备AlN陶瓷,研究了两类AlN陶瓷的相对密度、微观组织、力学性能和导热性能。结果表明:纯纳米AlN粉和掺杂Y2O3纳米AlN粉在40~60 MPa下,经1500 ℃放电等离子烧结5~60 min,均可获得相对密度>99%的AlN陶瓷。当烧结压力为50 MPa时,获得的AlN陶瓷晶粒尺寸最小,分别为176 nm和190 nm,细化晶粒明显提高了AlN陶瓷硬度和抗弯强度。当烧结时间从5 min延长至60 min时,两种AlN陶瓷晶粒尺寸分别增大至1.71 μm和1.73 μm。晶粒长大导致AlN陶瓷硬度和抗弯强度下降,但提升了导热性能。通过对比发现,相同放电等离子烧结工艺下添加烧结助剂Y2O3能够有效提升AlN陶瓷的综合性能。

    Abstract:

    AlN ceramics were prepared by spark plasma sintering (SPS) using the pure nano-AlN powders and the nano-AlN powders doped by 3% Y2O3 (mass fraction) as the raw materials. The relative density, microstructure, mechanical properties, and thermal conductivity of two types of AlN ceramics were studied. The results show that, both the pure nano-AlN powders and the nano-AlN powders doped by Y2O3 can obtain the AlN ceramics with the relative density above 99% prepared by SPS at 1500 ℃ for 5~60 min under 40~60 MPa. When the sintering pressure is 50 MPa, the average grain size of the AlN ceramics is the smallest, which is 176 nm and 190 nm, respectively. The hardness and bending strength of the AlN ceramics are obviously improved by the grain refinement. When the sintering time is extended from 5 min to 60 min, the grain size of the AlN ceramics is increased to 1.71 μm and 1.73 μm, respectively. The grain growth leads to the decrease of hardness and bending strength of the AlN ceramics, but improves the thermal conductivity. It is found that the addition of Y2O3 sintering agent can effectively improve the comprehensive properties of the AlN ceramics under the same SPS sintering process.

  • 锆酸钙材料(CaZrO3)具有优秀的抗水化性能、高熔点及良好的抗热震性能[1-5],拥有广阔的应用前景,由于自然界中不存在天然的CaZrO3,研究锆酸钙材料的合成就显得非常必要。制备CaZrO3的方法主要包括高温固相反应法、共沉淀法、溶胶-凝胶法、燃烧法和水热法等[6-8],高温固相法由于工艺简单、生产成本较低和生产量大等优点被人们广泛使用,但这种方法存在烧结温度高、制备锆酸钙致密性差等缺点。为了解决这些问题,研究者们在制备锆酸钙材料过程中向物系添加少量稀土氧化物、Al2O3、SiO2、CuO等添加剂,用于促进锆酸钙在低温下的烧结致密化;这些添加剂虽然可以起到促进锆酸钙材料烧结致密性的作用[9-11],但也会带来外来物质,降低CaZrO3高温使用性能。

    CaCO3作为制备CaZrO3的添加剂在高温下分解生成CaO,不会对CaZrO3产生污染;同时,由于CaCO3和制备原料Ca(OH)2分解温度不同,产生CaO晶体顺序不同,可以对CaO晶体质点的扩散产生影响。故本文考虑向锆酸钙材料中添加少量CaCO3微粉,利用分解温度不同,生成CaO晶体顺序不同,促进CaZrO3烧结致密性,降低锆酸钙烧结温度。

    以天津市科密欧化学试剂有限公司生产的分析纯Ca(OH)2和天津市光复精细化工研究生产的m-ZrO2为主要原料(平均粒度为7.4 μm和4.5 μm,纯度大于99%),实验中添加的CaCO3微粉为高纯微粉,纯度大于99%,其粒度分布如图 1示。可以看出,CaCO3微粉粒度较小,主要粒度分布在10 μm左右,D50为6 μm,D90为24 μm。

    图  1  CaCO3微粉的粒度分布
    Figure  1.  Particle size distribution of CaCO3 powders

    将Ca(OH)2和m-ZrO2按摩尔比1:1称量,等量分成五组,每组混合粉末中依次加入质量分数为0%、2%、4%、6%、8%和10%CaCO3微粉,再用卧式球磨机混合12 h,经过FLS手动四柱油压机在200 MPa压力下将混合粉末压制成ϕ20 mm圆柱试样,再用硅钼棒高温烧结炉在1600 ℃加热并保温3 h后随炉冷却到常温以备性能检测。

    烧结前将压好的试样放置在烘箱内110 ℃下保温24 h,取出冷却至常温,测量其高度(L0);试样经高温煅烧,冷却到常温后测量其烧后高度(L1),根据式(1)计算试样烧结前后线变化率(ΔLd)。

    $$ \Delta {L_{\rm{d}}} = \left[ {\left( {{L_1} - {L_0}} \right)/{L_0}} \right] \times 100\% $$ (1)

    利用阿基米德排水法检测试样煅烧后的体积密度和显气孔率[12]。煅烧后试样经切割、抛光及热处理后,采用扫描电子显微镜(scanning electron microscope,SEM)观察其组织形貌,使用X射线衍射仪(X-ray diffractometer,XRD)对其进行物相分析。

    图 2为烧结前后试样线变化率,从图 2可以看到,CaCO3微粉加入会改变试样线变化率。没有添加CaCO3微粉时,试样烧结前后线变化率为8.23%;当添加CaCO3微粉质量分数小于8%时,随CaCO3微粉添加量增大,试样烧结前后线变化率逐渐增大;当加入CaCO3微粉质量分数为8%时,试样收缩率达到最大值,为14.89%;继续增大CaCO3微粉添加量,试样烧结前后线变化率呈降低趋势。

    图  2  线变化率与添加CaCO3微粉质量分数的关系
    Figure  2.  Relationship between shrinkage and the CaCO3 addition content by mass

    图 3为高温煅烧后制备的锆酸钙体积密度和显气孔率,由图 3可以看到,CaCO3微粉的引入对制备的锆酸钙烧结性能产生影响。当没有添加CaCO3微粉时,制备的锆酸钙体积密度为3.4 g·cm-3,显气孔率为14.5%;随CaCO3质量分数增加,制备锆酸钙体积密度逐渐增加,显气孔率逐渐减小;当CaCO3微粉添加量为8%时,制备锆酸钙的体积密度最大,为4.02 g·cm-3,显气孔率最小,为8.6%;当CaCO3质量分数继续增大时,锆酸钙的体积密度开始降低,显气孔率反增大。

    图  3  烧结试样体积密度、显气孔率与添加CaCO3质量分数的关系
    Figure  3.  Relationship of bulk density, apparent porosity, and CaCO3 addition content by mass of sintering samples

    图 4为添加质量分数10%CaCO3制备样品的X射线衍射图谱,从图中可以看出,样品经1600 ℃保温3 h后主要物相为CaZrO3以及少量CaZr4O18

    图  4  添加质量分数10%CaCO3微粉制备样品的X射线衍射图谱
    Figure  4.  XRD patterns of samples add by CaCO3 powders in the mass faction of 10%

    图 5为添加不同质量分数CaCO3微粉的样品在1600 ℃烧后放大10000倍的扫描电子显微组织结构图。从图 5可以看出,CaCO3微粉质量分数小于8%时,随CaCO3微粉添加量的增大,试样致密性逐渐增加,锆酸钙晶粒尺寸逐渐变大,且晶体发育越来越均匀;当CaCO3微粉质量分数为8%时,锆酸钙晶粒尺寸最大,试样中基本无封闭气孔;当CaCO3微粉质量分数继续增大时,样品中出现封闭气孔,致密性变差,锆酸钙晶粒尺寸有变小趋势。

    图  5  添加不同质量分数CaCO3微粉的锆酸钙试样在1600 ℃烧结后扫描电子显微组织形貌:(a)0%;(b)2%;(c)4%;(d)6%;(e)8%;(f)10%
    Figure  5.  SEM micrographs of sintered CaZrO3 samples at 1600 ℃ added by CaCO3 powders in different mass fractions: (a) 0%; (b) 2%; (c) 4%; (d) 6%; (e) 8%; (f) 10%

    利用图象处理软件对图 5进行定量晶体大小测定,获得锆酸钙的平均晶粒尺寸,见表 1。可以发现,没有引入CaCO3微粉时,样品中锆酸钙晶粒尺寸最小为4.08 μm;随CaCO3微粉质量分数增大,锆酸钙晶粒尺寸逐渐增大;当CaCO3微粉质量分数为8%时,锆酸钙晶粒尺寸达到最大,为5.45 μm;当CaCO3微粉质量分数量继续增大时,锆酸钙晶粒尺寸反而变小。

    表  1  样品中CaCO3质量分数与锆酸钙晶粒直径的关系
    Table  1.  Relationship between CaZrO3 particle diameter and CaCO3 addition content by mass
    CaCO3质量分数/% 0 2 4 6 8 10
    CaZrO3晶粒直径/μm 4.08 4.43 4.88 5.08 5.45 5.21
    下载: 导出CSV 
    | 显示表格

    为了分析CaCO3微粉对锆酸钙烧结性能的影响,选取添加质量分数8%CaCO3微粉的试样,分别在500、600、700、800、900、1000及1100 ℃下保温3 h,分析在各个温度下烧后试样物相组成。图 6为试样在不同温度烧结后X射线衍射图谱。可以看出,试样经过500 ℃保温3 h后,物相组成没有太大变化;经过600 ℃保温3 h后,物相中开始有少量CaO出现,这是因为Ca(OH)2分解为CaO温度为580 ℃左右[13];当试样在700、800 ℃保温3 h后,Ca(OH)2质量分数逐渐减少,衍射峰逐渐减弱,CaO质量分数逐渐增大,衍射峰峰强逐渐增强,CaCO3衍射峰强在700 ℃之前逐渐增强,这是因为随烧结温度的升高,CaCO3晶粒发育越来越充分,烧成温度达到800 ℃时,CaCO3衍射峰强开始减弱,说明CaCO3开始分解为CaO;烧结温度为900 ℃时,CaCO3衍射峰逐渐减弱,CaO峰强增加迅速,这是因为CaCO3理论分解温度为850 ℃左右[14],分解生成高活性的CaO微晶均匀附着在Ca(OH)2分解形成CaO晶体表面,从而有利于CaO晶体扩散,可以促进CaO晶体长大,提高了CaO晶体的均匀性和生长致密性;继续升高烧结温度,CaCO3衍射峰强逐渐减弱乃至消失。

    图  6  添加质量分数8%CaCO3试样在不同温度烧结后X射线衍射图谱
    Figure  6.  XRD patterns of samples sintered at different temperatures add by CaCO3 powders in the mass faction of 8%

    当烧结温度达到900 ℃时,物相中开始出现CaZrO3衍射峰,说明开始生成CaZrO3。随烧结温度的提高,CaZrO3衍射峰强增加迅速,一部分原因是因为温度升高,CaZrO3迅速长大,另一部分原因是因为CaCO3分解CaO微晶附着在Ca(OH)2分解形成的CaO晶体表面,促进CaO晶体长大,为高温下CaO和ZrO2反应生成CaZrO3奠定基础。但添加过多的CaCO3微粉时,由于CaCO3在分解过程中产生过量CO2气体逸出形成大量的气体孔洞,不利于质点的迁移,导致烧结性能变差。

    (1)添加少量CaCO3微粉有利于锆酸钙烧结致密性。没有添加CaCO3微粉时,烧结温度为1600 ℃,锆酸钙体积密度为3.40 g·cm-3,显气孔率为14.5%;添加质量分数8%CaCO3微粉时,锆酸钙体积密度为4.02 g·cm-3,显气孔率为8.6%。

    (2)添加少量CaCO3微粉有利于锆酸钙晶粒长大。烧结温度为1600 ℃,无添加CaCO3微粉时,锆酸钙晶粒尺寸为4.08 μm;添加质量分数8%CaCO3微粉时,锆酸钙晶粒尺寸为5.45 μm。

  • 图  1   放电等离子烧结工艺示意图

    Figure  1.   Schematic diagram of the spark plasma sintering

    图  2   不同烧结时间AY0和AY3试样断口的场发射扫描电子显微镜背散射形貌:(a)AY0,5 min;(b)AY0,30 min;(c)AY0,60 min;(d)AY3,5 min;(e)AY3,30 min;(f)AY3;60 min

    Figure  2.   FESEM back scatter images of the AY0 and AY3 fracture microstructures with the different sintering times: (a) AY0, 5 min; (b) AY0, 30 min; (c) AY0, 60 min; (d) AY3, 5 min; (e) AY3, 30 min; (f) AY3, 60 min

    图  3   AY0和AY3试样硬度和抗弯强度与烧结时间关系:(a)维氏硬度;(b)抗弯强度

    Figure  3.   Hardness and bending strength of AY0 and AY3 with the different sintering times: (a) Vickers hardness; (b) bending strength

    图  4   不同烧结压力下AY0和AY3试样断口场发射扫描电子显微镜背散射形貌:(a)AY0,40 MPa;(b)AY0,50 MPa;(c)AY0,60 MPa;(d)AY3,40 MPa;(e)AY3,50 MPa;(f)AY3;60 MPa

    Figure  4.   FESEM back scatter images of the AY0 and AY3 fracture microstructures with the different pressures: (a) AY0, 40 MPa; (b) AY0, 50 MPa; (c) AY0, 60 MPa; (d) AY3, 40 MPa; (e) AY3, 50 MPa; (f) AY3, 60 MPa

    图  5   AY0和AY3试样力学性能随压力变化关系:(a)维氏硬度;(b)抗弯强度

    Figure  5.   Mechanical properties of AY0 and AY3 under the different pressures: (a) Vickers hardness; (b) bending strength

    图  6   AY0和AY3试样晶粒尺寸与抗弯强度关系

    Figure  6.   Relationship between the grain size and bending strength of the AY0 and AY3 samples

    图  7   AY0和AY3试样热导率(a)和物相组成(b)随烧结时间变化

    Figure  7.   Thermal conductivity (a) and phases composition (b) of AY0 and AY3 with the different sintering times

    表  1   不同烧结时间放电等离子烧结试样的相对密度和平均晶粒尺寸

    Table  1   Relative densities and the average grain sizes of the SPS samples for the different sintering times

    样品相对密度 / %晶粒尺寸 / nm
    5 min30 min60 min5 min30 min60 min
    AY099.2599.4699.332833321710
    AY399.1299.3999.0776716701730
    下载: 导出CSV

    表  2   不同烧结压力下试样的平均晶粒尺寸和相对密度

    Table  2   Average grain sizes and the relative densities of the SPS samples under the different pressures

    样品相对密度 / %晶粒尺寸 / nm
    40 MPa50 MPa60 MPa40 MPa50 MPa60 MPa
    AY099.0699.5699.48283176574
    AY399.2799.4499.52513190353
    下载: 导出CSV
  • [1] 张永清, 阴生毅, 高向阳, 等. 新型高热导率氮化铝基微波衰减陶瓷研究. 稀有金属材料与工程, 2020, 49(2): 655

    Zhang Y Q, Yin S Y, Gao X Y, et al. Study on aluminum nitride microwave attenuation ceramics with high thermal conductivity. Rare Met Mater Eng, 2020, 49(2): 655

    [2] 张静波, 牛通, 崔凯, 等. 氮化铝多层共烧陶瓷基板的化学镀镍钯金技术. 电子机械工程, 2020, 36(1): 42

    Zhang J B, Niu T, Cui K, et al. Technology of ENEPEG on AlN HTCC. Electron Mech Eng, 2020, 36(1): 42

    [3] 陈丽洁, 徐兴烨, 雷亚辉, 等. 新型氮化铝AlN晶体高温压电振动传感器. 中国电子科学研究院学报, 2020, 15(12): 1212

    Chen L J, Xu X Y, Lei Y H, et al. A novel piezoelectric vibration sensor with aluminum nitride crystal at high temperature. J China Acad Electron Inf Technol, 2020, 15(12): 1212

    [4] 盛鹏飞, 聂光临, 黎业华, 等. 高导热氮化铝陶瓷成型技术的研究进展. 陶瓷学报, 2020, 41(6): 771

    Sheng P F, Nie G L, Li Y H, et al. Research progress in shaping technology of AlN ceramics with high thermal conductivity. J Ceram, 2020, 41(6): 771

    [5]

    Molisani A L, Goldenstein H, Yoshimura H N. The role of CaO additive on sintering of aluminum nitride ceramics. Ceram Int, 2017, 43(18): 16972 DOI: 10.1016/j.ceramint.2017.09.104

    [6]

    He X L, Ye F, Zhang H J, et al. Study of rare-earth oxide sintering additive systems for spark plasma sintering AlN ceramics. Mater Sci Eng A, 2010, 527(20): 5268 DOI: 10.1016/j.msea.2010.04.098

    [7] 王露露, 马北越, 刘春明, 等. AlN陶瓷热导率及抗弯强度影响因素研究的新进展. 耐火与石灰, 2023, 48(1): 23 DOI: 10.3969/j.issn.1673-7792.2023.1.gwnhcl202301007

    Wang L L, Ma B Y, Liu C M, et al. The latest research progress on thermal conductivity and bending strength of AlN ceramics. Refract Lime, 2023, 48(1): 23 DOI: 10.3969/j.issn.1673-7792.2023.1.gwnhcl202301007

    [8] 王露露, 马北越, 刘春明, 等. AlN陶瓷烧结技术及性能优化研究进展. 耐火材料, 2022, 56(2): 180

    Wang L L, Ma B Y, Liu C M, et al. Research progress on sintering technology and performance optimization of AlN ceramics. Refractories, 2022, 56(2): 180

    [9]

    Troczynski T B, Nicholson P S. Effect of additives on the pressureless sintering of aluminum nitride between 1500 and 1800 ℃. J Am Ceram Soc, 1989, 72(8): 1488 DOI: 10.1111/j.1151-2916.1989.tb07684.x

    [10] 徐耕夫, 李文兰, 庄汉锐, 等. 氮化铝陶瓷的微波烧结研究. 硅酸盐学报, 1997, 25(1): 89

    Xu G F, Li W L, Zhuang H R, et al. Microwave sintering of AlN ceramics. J Chin Ceram Soc, 1997, 25(1): 89

    [11]

    Groza J R, Risbud S H, Yamazaki K. Plasma activated sintering of additive-free AlN powders to near-theoretical density in 5 minutes. J Mater Res, 1992, 7(10): 2643 DOI: 10.1557/JMR.1992.2643

    [12]

    Akimoto S, Kijima K, Kitamura M. Time dependence of AlN densification by plasma sintering. J Ceram Soc Jpn, 1992, 100(1158): 196 DOI: 10.2109/jcersj.100.196

    [13] 张博文, 马北越, 尹月, 等. SPS制备陶瓷及钛合金材料的新进展. 耐火材料, 2017, 51(2): 157 DOI: 10.3969/j.issn.1001-1935.2017.02.018

    Zhang B W, Ma B Y, Yin Y, et al. Latest development on ceramics and titanium alloy materials welded by SPS. Refractories, 2017, 51(2): 157 DOI: 10.3969/j.issn.1001-1935.2017.02.018

    [14]

    Langer J, Hoffmann M, Guillon O. Electric field-assisted sintering and hot pressing of semiconductive zinc oxide: a comparative study. J Am Ceram Soc, 2011, 94(8): 2344 DOI: 10.1111/j.1551-2916.2011.04396.x

    [15]

    Chaim R. Densification mechanisms in spark plasma sintering of nanocrystalline ceramics. Mater Sci Eng A, 2007, 443: 25 DOI: 10.1016/j.msea.2006.07.092

    [16]

    Wu J Y, Chen F, Shen Q, et al. Spark plasma sintering and densification mechanisms of antimony-doped tin oxide nanoceramics. J Nanomater, 2013, 2013(1-3): 2

    [17]

    Saheb N, Iqbal Z, Khalil A, et al. Spark plasma sintering of metals and metal matrix nanocomposites: a review. J Nanomater, 2012, 2012: 983470

    [18]

    Wang X T, Padture N P, Tanaka H. Contact-damage-resistant ceramic/single-wall carbon nanotubes and ceramic/graphite composites. Nat Mater, 2004, 3(8): 539 DOI: 10.1038/nmat1161

    [19]

    Shen Z J, Zhao Z, Peng H, et al. Formation of tough interlocking microstructures in silicon nitride based ceramics by dynamic ripening. Nature, 2002, 417(6886): 266 DOI: 10.1038/417266a

    [20]

    Basu B, Venkateswaran T, Kim D Y. Microstructure and properties of spark plasma-sintered ZrO2-ZrB2 nanoceramic composites. J Am Ceram Soc, 2006, 89(8): 2405 DOI: 10.1111/j.1551-2916.2006.01083.x

    [21]

    He Q, Qin M L, Huang M, et, al. Mechanism and kinetics of combustion-carbothermal synthesis of AlN nanopowders. Ceram Int, 2017, 43(12): 8755 DOI: 10.1016/j.ceramint.2017.04.006

    [22]

    Pezzotti G, Nakahira A, Tajika M. Effect of extended annealing cycles on the thermal conductivity of AlN/Y2O3 ceramics. J Eur Ceram Soc, 2000, 20(9): 1319 DOI: 10.1016/S0955-2219(99)00286-1

    [23]

    Bernard-Granger G, Addad A, Fantozzi G, et al. Spark plasma sintering of a commercially available granulated zirconia powder: comparison with hot-pressing. Acta Mater, 2010, 58(9): 3390 DOI: 10.1016/j.actamat.2010.02.013

    [24]

    Langer J, Hoffmann M J, Guillon O. Direct comparison between hot pressing and electric field-assisted sintering of submicron alumina. Acta Mater, 2009, 57(18): 5454 DOI: 10.1016/j.actamat.2009.07.043

    [25]

    Langer J, Hoffmann M J, Guillon O. Electric field-assisted sintering in comparison to hot pressing of yttria-stabilized zirconia. J Am Ceram Soc, 2011, 94(1): 24 DOI: 10.1111/j.1551-2916.2010.04016.x

    [26]

    Fang Z G, Wang H T, Kumar V. Coarsening, densification, and grain growth during sintering of nano-sized powders-A perspective. Int J Refract Met Hard Mater, 2017, 62: 110 DOI: 10.1016/j.ijrmhm.2016.09.004

  • 期刊类型引用(1)

    1. 路跃,刘国齐,杨文刚,燕鹏飞,马渭奎,李红霞. 烧结助剂对锆酸钙材料性能的影响. 耐火材料. 2023(05): 407-411 . 百度学术

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  • 收稿日期:  2023-04-16
  • 录用日期:  2023-04-16
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  • 刊出日期:  2024-02-27

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