• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Symposium on Nontraditional Methods of Sensing Stress, Strain, and Damage in Materials and Structures held on 20 May 1996. >An Advanced Multiple Frequency Acpd System for Crack Detection and Calibration
【24h】

An Advanced Multiple Frequency Acpd System for Crack Detection and Calibration

机译：先进的多频率Acpd系统，用于裂纹检测和校准

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

On-line crack detection and crack depth measurements have been carried out using a novel sensor. The sensor is based on an advanced alternating current potential difference (ACPD) technique. This sensor makes use of a new technology called current focusing (CF) which allows the current distributtion on the surface to be selectively confined to a precise region (e.g., in a high stress gradient domain). The use of AC currents in conjunction with the current focusing technique results in having a three - dimensional control of the current density distribution in a solid. As a result, the technique can be used on large structures as well as on standard specimens. The associated advanced electronics, having variable frequency capabilities (500 Hz to 240 kHz) and variable currents up to 5 Amperes has been designed and will be briefly described. To assess the performance of the system and ACPD/CF technologies, a fatigue testing program was carried out on single edge notch specimens made of Al 7075 alloys. Naturally initiated fatigue cracks in the range of 200 mum to 6mm have been detected. Potential difference versus crack depth calibrations curves were obtained for various combinations of currents and frequencies with a reliability better than 90percent. Furthermore, off-line measurements have been carried out to assess the applicability of the technique for NDI applications.
机译：在线裂缝检测和裂缝深度测量已经使用新型传感器进行。该传感器基于先进的交流电势差（ACPD）技术。该传感器利用一种称为电流聚焦（CF）的新技术，该技术可将表面上的电流分布选择性地限制在精确的区域内（例如，在高应力梯度域内）。交流电流与电流聚焦技术结合使用可对固体中的电流密度分布进行三维控制。结果，该技术可用于大型结构以及标准样品。具有可变频率能力（500 Hz至240 kHz）和可变电流高达5安培的相关先进电子设备已经过设计，并将简要介绍。为了评估系统和ACPD / CF技术的性能，对Al 7075合金制成的单边缺口试样进行了疲劳测试程序。已发现200毫米至6毫米范围内的自然引发的疲劳裂纹。获得了电流和频率的各种组合的电势差与裂纹深度的校准曲线，其可靠性优于90％。此外，已经进行了离线测量以评估该技术在NDI应用中的适用性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号