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

基本信息

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

项目摘要

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.

新开发的紧凑型水平水平型左室型疲劳测试机已在扫描激光显微镜下施加轴向载荷，并改善了原位观察系统。在以下内容中显示了改进系统的特征。（1）在轴向载荷期间，最高（]SY。+ - 。[）98KN时，可以在周围空气中观察样品表面。（2）载荷控制或位置受控疲劳测试的频率为0.001 tens hz可以在carreight上均可使用。移动2MUM精度。同样，疲劳测试期间视野的运动可以通过计算机控制的自动阶段来取消。（4）由于设置了特殊的旋转夹具，因此可以观察到整个样品的整个圆圈。通过使用此系统，详细观察到TIAL金属层间化合物的疲劳过程。 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.而且，随着应力周期数量的增加，滑动线的数量增加。结论是，累积的滑动变形会导致TIAL的疲劳骨折，以及传统金属材料的疲劳。这证实了新开发的疲劳测试机和改进的扫描激光显微镜类型原位观察系统功能良好。通过设置其他设备，原位观察将能够在水中或温度升高时进行。