SBIR PHASE II: High Perfromance Nondestructive Evaluation System Using Giant Magnetoresistance Sensors

该小型企业创新研究第二阶段项目将进行必要的研究，以设计和开发一个基于巨磁阻（GMR）材料制成的传感器的全功能无损评估（NDE）系统。第一阶段的研究表明，基于这种传感器的无损检测系统具有大大优于当前无损检测技术的上级性能。 使用简单、低成本的传感器和电子系统以及专有的分析技术，可以检测铝和钢板中宽度在20微米至100微米范围内的裂缝，信噪比（S/N）超过100。 更重要的是，对飞机截面的试验表明，在高信噪比水平下，可以检测到上覆金属板下和铆钉头下的裂纹。 这些结果表明，新技术将代表NDE能力的重大进步，对安全，效率和成本节约具有相当大的影响。 随着国家交通和民用结构的老化和复杂性的增加，改进NDE技术的重要性也被放大。 由于缺乏适当的技术，许多现有的在役检查（ISI）程序仅使用目视检查进行。 这种高灵敏度、深穿透的电磁传感器将为包括商用和军用飞机、压力容器和管道在内的导电结构中的嵌入式缺陷提供快速、具有成本效益的检测。

This Small Business Innovation Research Phase II project will conduct the research necessary to design and develop a fully functional non-destructive evaluation (NDE) system based on sensors made with giant magnetoresistance (GMR) materials. Phase I research demonstrated that an NDE system based on such sensors has vastly superior performance to current NDE techniques. Using a simple, low cost sensor and electronics system, and a proprietary analytical technique, it was possible to detect creacks with widths in the 20 microns to 100 microns range in both aluminum and steel sheets, with signal-to-noise (S/N) ratios exceeding 100. Of even greater importance, tests with an aircraft section showed it was possible to detect cracks beneath overlying sheets of metal, and under rivet heads at high S/N levels. These results indicate the new technology will represent a major advance in NDE capability, with considerable implications for safety, efficiency and cost savings. As both the age and complexity of the nation's transportation and civil structures increase, the importance of improved NDE technology is amplified. Due to the lack of appropriate technology, many existing in-service inspection (ISI) programs are conducted using visual inspection only. This high-sensitivity, deeply penetrating electromagnetic sensor would provide rapid, cost-effective inspection for embedded defects in electrically conductive structures including commercial and military aircraft, pressure vessels and pipelines.