Tunneling Magneto Resistive Sensors, their Construction and Potential Applications

Abstract

The long-term goal of our research is aimed at the development of a sensor capable of detecting cracks in the structures of aerospace vehicles. Particular points of interest are airframes and' wing structures where plates join together and overlap in a riveted joint. These cracks can lead to the failure of these joints. Current sensors can detect cracks on the surface but have a difficult time penetrating into deeper depths where these potentially lethal cracks can develop. Development and incorporation of a sensor with tunneling magneto-resistance (TMR) effects of a ferromagnet - insulator - ferromagnet compound for a small and inexpensive hand held sensor would prove to be very effective in finding these cracked rivet joints. This research is focused on the development of Tunneling Magneto Resistive materials with the potential of fulfilling this need.