An Embeddable Corrosion Rate Meter for Remote Monitoring of Infrastructures

Reference#: P01858

Corrosion of infrastructure and fluid containing vessels and pipelines is a continuing situation if the United States for both government agencies and industry. Existing methods, which include implied monitoring techniques and sacrificial coupons are both costly and labor intensive. The need is for a direct reading sensor, which emulates the actual corrosion occurring to the metal surfaces. The sensor needs to be long life, miniature, wireless and accessible to periodic readout techniques.

The Johns Hopkins University Applied Physics Laboratory has developed and is in the patent process of the Embedded Corrosion Rate Meter (ECRM), which uses the basic principle known as chronovoltammetry, i.e., Voltage-Time Response. In addition the ECRM provides the flexibility of using another principle known as alternating current (AC) impedance or Electrochemical Impedance Spectroscopy (EIS) to give an estimate of the corrosion rate. The sensor electrodes for the ECRM are in contact with the fluid or medium subject to corrosion and act just like the metal surface being monitored. The electrodes are the external part of the APL developed wireless Embedded Sensor Platform (WESP) which takes the signal and prepares it to be relayed wirelessly to a portable readout device. ECRM is very small, has a rugged exterior for long life. The sensor must be mounted so that there is a clear non-magnetic path between the sensor and the readout device. This makes ECRM applicable to concrete structures measuring the corrosion in rebar, vessels and pipelines measuring the internal corrosion using a sight glass porthole.

Patent Status: U.S. patent(s) 7148706 issued.

Additional References:

Patent Drawing