Development of Nondestructive Evaluation System Using the Excitation Type High Sensitivity Magnetic Sensor to Ddetect Fatigue Damage of Metallic Material

激励式高灵敏度磁传感器检测金属材料疲劳损伤无损评价系统的研制

基本信息

批准号：
15560371
负责人：
OKA Mohachiro
金额：
$ 2.43万
依托单位：
Oita National College of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

In this project, we have elucidated the following results for the evaluation of fatigue damage in an austenitic stainless steel using the FG magnetic sensor and we developed the non-destructive evaluation system using the excitation type high sensitivity magnetic sensor to detect fatigue damage of metallic material.In order to estimate the amount of bending fatigue damage on austenitic stainless steel plates, we have investigated the relationship between plane bending stress and residual magnetization caused by martensitic structure in austenitic stainless steel plates. Magnetic flux density in the Z component caused by residual magnetization at 1 mm above a specimen is measured by using a high sensitivity thin-film flux-gate magnetic sensor.The eddy current probe which is a new magnetic sensor to detect fatigue damage on austenitic stainless steels consists of an excitation coil and two pick-up coils wound on a ferrite core. The size of the EC probe is 10 mm x 4 mm x 8 mm.Results of this project are shown as follows:1) The value of B_<zmax> clearly increases with the increase of the bending stress (σ_a) and N.2) The value of B_<zmax> is a useful parameter to estimate the amount of fatigue damage.3) We could detect the small leakage magnetic flux density on the specimens such as SUS304, SUS304L, SUS316 and SUS316L caused by the residual magnetization by using the FG magnetic sensor.4) The residual magnetization in SUS316 series is about ten times smaller than SUS304 series.5) This new eddy current probe was surely able to catch the change in electromagnetic properties such as magnetic permeability caused by the transformation from austenite to martensite in SUS304.6) The value of Rc_<max> obviously depends on the number of stress cycles.

In this project, we have elucidated the following results for the evaluation of fatigue damage in an austenitic stainless steel using the FG magnetic sensor and we developed the non-destructive evaluation system using the excitement type high sensitivity magnetic sensor to detect fatigue damage of metallic material.In order to estimate the amount of bending fatigue damage on austenitic stainless steel plates, we have investigated the relationship between plane bending stress and residual奥氏体不锈钢板中的马氏体结构引起的磁化。通过使用高灵敏度薄膜磁通磁力磁性传感器来测量标本上方1 mm的残留磁化引起的Z组件中的磁通量密度。涡流探针是一种新的磁性传感器，它是检测到奥斯汀质钢对抗螺旋体的疲劳损害的新磁性传感器。 EC探头的大小为10 mm x 4 mm x 8 mm。该项目的重新点表示：1）B_ <Zmax>的值清楚地随着弯曲应力的增加（σ_a）和N.2的增加而显然增加，B_MAX>的值是B_ <Zmax>的价值，这是一个有用的参数。 SUS304L，SUS316和SUS316L由使用FG磁性传感器引起的残余磁化引起。4）SUS316系列中的残留磁化比SUS304系列小约十倍。5）5）这种新的涡流探针肯定能够捕获诸如MARTCENITE ressenite insenite inscy inscy insunite insce in of Martcy的磁性磁性的变化，例如，MARTRC insente in Come of Martcy 30 extrance in osters inscemente <66关于应力周期的数量。