Development of Low-Temperature Processes for High-Temperature Intermetallic Compounds and their microstructure control

高温金属间化合物低温工艺开发及其微观结构控制

• 批准号: 07555228
• 负责人: MARUYAMA Toshio
• 金额: $ 3.9万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555228/
• 关键词: Mo(Si, Al)_2; Nb(Si, Al)_2; Nb(Al, Si)_3; intermetallic compounds; hot dipping; self-propagation; liquid-phase reactive sintering; 低温合成; 高温酸化; 表面コーティング

(1) DIP COATING OF Nb BY USING Al-Si LIQUIDBy dipping of Nb in Si-saturated Al liquid at temperatures from 940 K to 1140 K,C40-type Nb(Si_<0.9>, Al_<0.1>)_2 layr formed at the interface on Nb. The intermetallic layr consisted of fine particles with submicrons in diameter and included Al-Si liquid between particles. The growth of Nb(Si, Al)_2 layr was rate-controlled by the dissolution-precipitation reaction at the Nb/Nb(Si, Al)_2 interface. The growth rate of Nb(Si, Al)_2 was 3 times faster than that of Mo(Si, Al)_2 in the Mo dipping.In the dipping of Nb in non-saturated Al-Si liquid at 1025 K,C40-type Nb(Si, Al)_2 formed with Al-23 mol% Si liquid. The growth rate was faster than that in the case of the saturated Al-Si liquid. Product layr by dipping Nb in Al-Si liquid with around 20 mol% Si exhibited the layr-by-layr structure consisting of C40-type Nb(Si, Al)_2 and D0_<22>-type Nb(Al, Si)_3. With decreasing Si content down to 5 mol% in Al-Si liquid, the product layr consisted of the … More D0_<22>-type Nb(Al, Si)_3. Their results imply that C54-type Nb(Si, Al)_2 does not exist in the Nb-Si-Al system at 1025 K.(2) MECHANISM OF DIP COATING USING Al-Si LIQUID :By dipping Mo in Si-saturated Al liquid, C40-type Mo(Si, Al)_2 layr formed on Mo. The C40-type intermetallic layr was comprised of needle-like Mo(Si, Al)_2 grains with Al-Si liquid at grain boundary. The needle-like grains grow by dissolution-precipitation process through Al-Si liquid at the interface between Mo(Si, Al)_2 and Mo.The mechanism of the growth of C40-type intermetallic layr is the dissolution-precipitation process through Al-Si liquid at the interface between Mo or Nb and the product layr. The difference of grain shape on Mo(Si, Al)_2 and Nb(Si, Al)_2 is discussed with the phase relation and supply and consumption of Al and Si from the liquid phase in the interface. The formation of the layr-by-layr structure in the Nb dipping was explained by the consumption of Al and Si with different ratios for D0_<22> and C40.(3) DEVELOPMENT OF CRACK=FREE COATING BY DIPPING USING Al-Si LIQUIDAddition of Cr, Nb, Ta and Ti in Al-Si liquid was carried out in order to prevent the formation of cracks of Mo(Si, Al)_2 layr on Mo surface with large curvature. The dipping of MO into Al-Si-Cr liquid leads to the formation of the crack-free layr. In the dipping with Al-Si-Cr liquid, (Cr, Mo) (Si, Al)_2 grains formed on the Mo(Si, Al)_2 layr. There is no change ofthe chemical composition and the growth rate of Mo(Si, Al)_2 by addition of Cr in Al-Si liquid.(4) LIQUID-PHASE REACTIVE SINTERING OF Mo-Si-Al POWDER MIXTURELiquid-phase reactive sintering of Mo-Si-Al powdr mixture were investigated. In the powder mixture with high Al content, self-propagation reaction occurred and Mo(Si, Al)_2 formed. The sintered bodies have porous structure. Less

(1)Al-Si液浸镀Nb将Nb浸入Si饱和的Al液中，温度为940K～1140K，形成C40型Nb(Si_<0.9>,Al_<0.1>)_2层。 Nb界面上的金属间化合物层由直径为亚微米级的细小颗粒组成，颗粒间含有Al-Si液体。 Nb(Si, Al)_2层通过Nb/Nb(Si, Al)_2界面处的溶解-沉淀反应进行速率控制，Nb(Si, Al)_2的生长速率比Mo快3倍。 (Si, Al)_2在Mo浸渍中。Nb在1025 K的非饱和Al-Si液体中浸渍时,与Al-23形成C40型Nb(Si, Al)_2 mol% Si 液体的生长速率比通过将 Nb 浸入具有约 20 mol% Si 的 Al-Si 液体中的产物层更快，表现出由 C40 组成的层状结构。 -型Nb(Si, Al)_2和D0_<22>-型Nb(Al, Si)_3。随着Al-Si液体中Si含量降低至5 mol%，产物层开始...更多的D0_<22>型Nb(Al,Si)_3表明在1025K时Nb-Si-Al体系中不存在C54型Nb(Si,Al)_2。(2)DIP机理使用Al-Si液体涂层：通过将Mo浸入Si饱和的Al液体中，在Mo上形成C40型Mo(Si, Al)_2层。C40型金属间层由针状Mo(Si,Al)_2晶粒和晶界Al-Si液体组成,针状晶粒通过Al-Si液体在Mo(Si,Al)之间的界面处通过溶解-沉淀过程生长。 )_2和Mo。C40型金属间化合物层的生长机理是Al-Si液体在Mo或Nb与产物层界面上的溶解-沉淀过程中晶粒形状的差异。讨论了Mo(Si,Al)_2和Nb(Si,Al)_2的相关系以及界面中Al和Si的供给和消耗以及Nb中层状结构的形成。浸渍是通过消耗具有不同比例的 D0_22 和 C40 的 Al 和 Si 来解释的。 (3) 使用 Al-Si 液体浸渍，形成无裂纹=无涂层为了防止大曲率Mo表面Mo(Si,Al)_2层裂纹的形成，将Cr、Nb、Ta、Ti在Al-Si液中进行浸渍。导致无裂纹层的形成，在用Al-Si-Cr液体浸渍时，Mo(Si，Al)_2层上形成的(Cr，Mo)(Si，Al)_2晶粒没有变化。化学品的(4) Mo-Si-Al粉末混合物的液相反应烧结Mo-Si-Al粉末的液相反应烧结研究发现，在高Al含量的粉末混合物中，发生自蔓延反应并形成具有多孔结构的Mo(Si,Al)_2。较少的

项目成果

鎌田 弘之: "MoとAl-Si-X融体(X=Cr,Nb,Ta,Ti)との反応により生成するMo(Si,Al)2の組織とその制御" 1998年春期(第121回)大会日本金属学会講演概要. (1998)

Hiroyuki Kamata：“Mo和Al-Si-X熔体反应形成的Mo(Si,Al)2的结构和控制（X=Cr,Nb,Ta,Ti）”1998年春季（第121次会议））会议摘要日本金属研究所讲座（1998）。

南口 誠: "Si飽和Al融体中のNbおよびMo上に生成したダイシリサイドの微細組織" 1996年秋期(第121回)大会日本金属学会講演概要. 396- (1997)

Makoto Minamiguchi：“硅饱和铝熔体中 Nb 和 Mo 上形成的二硅化物的微观结构”日本金属学会 1996 年秋季（第 121 届）会议的演讲摘要 396-（1997 年）。

M.Nanko: "Microstructure of Disilicides Formed on Nb or Mo in Si saturated Al Liquid" Abst.1996 Fall Meeting of Japan Institute of Metals. 396 (1996)

M.Nanko：“硅饱和铝液中 Nb 或 Mo 上形成的二硅化物的微观结构”Abst.1996 年日本金属学会秋季会议。

高橋明男: "Si飽和Al融体を用いた超高温金属間化合物の合成" 1996年春期(第118回)大会日本金属学会講演概要. 90 (1996)

Akio Takahashi：“使用硅饱和铝熔体合成超高温金属间化合物”1996 年春季（第 118 届）日本金属学会会议摘要 90（1996）。

A.Takahashi: "Synthesis of High Temperature Intermetalic Comounds by Using Si Saturated Al Liquids" Abst.1996 Spring Meeting of Japan Institute of Metals. 90 (1996)

A.Takahashi：“使用硅饱和铝液体合成高温金属间化合物”摘要。1996 年日本金属学会春季会议。