Improvement of scanning laser microscope type in situ observation system and microscopic observation of fracture process in intermetallic compounds

扫描激光显微镜式原位观察系统改进及金属间化合物断裂过程显微观察

• 批准号: 06650121
• 负责人: UENO Akira
• 金额: $ 0.19万
• 依托单位: Toyota Technological Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650121/
• 关键词: Scanning laser microscope; In situ observation system; Microscopic fracture process; Intermetallic compounds; TiAl; Crack initiation; Crack propagation; Fracture mechanics; 微視破壊現象

The compact horizontal type elctric-hydrauric fatigue testing machine which could apply axial load under the scanning laser microscope was newly developed, and in situ observation system was improved. Characteristic of the improved system are shown in the following.(1) During axial load of up to (]SY.+-。[) 98kN is applied, the specimen surface can be observed in the ambient air with high magnification.(2) Load controlled or position controlled fatigue test with frequency of 0.001-tens Hz can carreid out.(3) As the testing machine is placed on a computer-controlled X-Y automatic stage, the observation point can be moved of 2mum accuracy. Also, movement of visual field during fatigue test can be cancelled by the computer-controlled automatic stage.(4) Because a special rotation jig is set, the whole circumference of the specimen can be observed.By using this system, fatigue process of the TiAl intermetallic compounds are observed in detail. To study a basic S-N characteristics, fatigue tests attended with surface observation were carried out under sine wave of stress ratio R=-1, by using a Ti-33.8wt.% Al.Although TiAl hardly deformed plastically, several types of slip (single slip, double slip, twin) which were the evidence of the plastic deformation were oberved in some of gamma-TiAl grain. Also, number of slip lines were increased as number of stress cycles increased. It is concluded that the accumulated slip deformation causes the fatigue fracture of TiAl, as well as the fatigue in traditional metallic materials.It is confirmed that the newly developed fatigue testing machine and the improved scanning laser microscope type in situ observation system function well. By setting up additional apparatus, in situ observation will be able to carry out in water or at elevated temperature.

研制了一台小型卧式电液疲劳试验机，可在激光扫描显微镜下施加轴向载荷，并改进了原位观察系统。改进后的系统特点如下。(1)在轴向载荷高达（]SY. ±. [）施加98 kN，可以在环境空气中以高放大率观察试样表面。(2)可进行频率为0.001- 10 Hz的载荷控制或位置控制疲劳试验。(3)由于试验机放置在计算机控制的X-Y自动工作台上，观察点可以移动2 μ m的精度。此外，在疲劳测试过程中的视野移动可以被计算机控制的自动阶段取消。(4)由于设置了特殊的旋转夹具，可以对试件的整个圆周进行观察，利用该系统对TiAl金属间化合物的疲劳过程进行了详细的观察。为了研究钛合金的基本S-N特性，在应力比R=-1的正弦波加载下，对Ti-33.8wt.%γ-TiAl晶粒几乎不发生塑性变形，但在部分γ-TiAl晶粒中观察到了塑性变形的几种滑移类型（单滑移、双滑移、孪晶）。此外，随着应力循环次数的增加，滑移线的数量也增加。结果表明，TiAl合金的疲劳断裂与传统金属材料的疲劳断裂一样，都是由累积滑移变形引起的，并证实了新研制的疲劳试验机和改进的扫描激光显微镜式原位观察系统的良好性能。通过增设仪器，可在水中或高温下进行原位观测。

项目成果

上野 明,岸本秀弘他1名: "金属間化合物TiAlの応力腐食割れ" 日本機械学会東海支部第44期総会講演会講演論文集. No.953-1. 118-119 (1995)

Akira Ueno、Hidehiro Kishimoto 等 1：“金属间化合物 TiAl 的应力腐蚀裂纹”第 44 届日本机械工程学会东海分会会议记录第 953-119 号（1995 年）。

A.Ueno et.al.: "Stress Corrosion Cracking In TiAl Intermetallic Compounds" Proc.of the 44th Sympo.on General Meeting, JSME Tokai subdivision. No.953-1. 118-119 (1994)

A.Ueno 等人：“TiAl 金属间化合物中的应力腐蚀开裂”Proc.of the 44th Sympo.on General Meeting，JSME Tokai subdivision。

上野 明・岸本秀弘他1名: "金属間化合物TiAlの応力腐食割れ" 日本機械学会東海支部第44期総会講演会講演論文集. No.953-1. 118-119 (1995)

Akira Ueno、Hidehiro Kishimoto 等 1：“金属间化合物 TiAl 的应力腐蚀裂纹”第 44 届日本机械工程学会东海分会会议记录第 953-119 号（1995 年）。

上野,明: "レーザー顕微鏡による表面観察I(素材試験への応用)" 材料科学. 31. 62-69 (1994)

Ueno，Akira：“使用激光显微镜进行表面观察 I（在材料测试中的应用）”材料科学 31. 62-69 (1994)。

上野 明・岸本秀弘他1名: "金属間化合物TiAlの中高温下における疲労き裂成長挙動" 日本材料学会第44期学術講演会講演論文集. 179-180 (1995)

Akira Ueno、Hidehiro Kishimoto 等 1：“中高温下金属间化合物 TiAl 的疲劳裂纹扩展行为”日本材料学会第 44 届学术会议论文集 179-180（1995）。