Abstract: An electro-chemical sensor comprises a bismuth nano-wire array. The sensor is used to detect incipient corrosion under paint. It is particularly useful in admiralty and marine applications such as for detecting incipient metal oxidation such as rusting and for monitoring the progress of metal oxidation on ship hulls and tanks. It is also useful in the automobile industry for quantifying surface quality in preparation for painting.

Abstract: The corrosion inhibiting activity of a coating is determined from the effect of corrosion inhibiting species released by the coating on the oxygen reduction current for a cathode placed very close to the coating. A rotating disk electrode or pumped solution flow is used to sweep the corrosion inhibiting species from the coating surface to the cathode. The oxygen reduction current is measured under conditions of oxygen diffusion control.

Abstract: A corrosion sensor system includes a substrate with a hydrophilic coating and a sensor array attached to the substrate, the sensor array manufactured of a noble metal. The sensor system operates to determine a time of wetness measurement based upon an electrolyte conductivity and a temperature.

Abstract: A method and system for determining chemical properties of a fluid. The method and system include providing a weak electrolyte fluid, a container for the fluid, a detection method performed by a device having at least two electrodes, a detection and amplification device coupled to the electrodes and a sensed current compared to an uncontaminated, base fluid or compared to data characteristic of fluid contaminated or chemically changed in order to monitor and characterize the fluid.

Abstract: A cathodic protection system for use in an electrolyte includes a protected structure to be at least partially immersed in the electrolyte, at least one sacrificial anode to be at least partially immersed in the electrolyte and electrically connected to the protected structure, and a substantially impermeable barrier disposed between the at least one sacrificial anode and the electrolyte.

Abstract: In one example, a specimen is immersed in an electrolyte, and a plurality of potentials of the specimen are experimentally related to a plurality of currents by applying the potentials to the specimen while measuring the currents, or, by drawing the currents through the specimen while measuring the potentials. The potentials are referenced to a hydrogen reference electrode. Hydrogen is supplied to the hydrogen reference electrode via an electrolysis cathode distinct from the hydrogen reference electrode. In another example, an electrochemical cell confines a head gas disposed over the electrolyte. A partial pressure of water vapor in the head gas is adjusted so that the concentration of water in the electrolyte, when equilibrated with the head gas, falls within a predetermined concentration range. The head gas and electrolyte are then equilibrated, thereby controlling the concentration of water in the electrolyte, and an electrochemical property of the specimen is measured.

Abstract: A method and apparatus for sensing corrosion comprises a casing and a counter-electrode. The casing is made of material that is substantively incompressible at pressures on wires within a structural cable. The casing has a thickness that is not greater than typical interstitial spaces between wires of the structural cable and has a length on an order of a radius of the structural cable. The counter-electrode exchanges electrons with ions of an electrolyte that corrodes the wires of the structural cable. The counter-electrode is embedded in the casing, is exposed to the electrolyte in a window of the casing, and is recessed to avoid contact with any wire of the structural cable when the sensor is deployed among the wires of the structural cable.

Abstract: An electrochemical corrosion potential sensor (ECP sensor) has an electrode cap, an electrode fixing body, a tubular insulator, a tubular metallic housing, and a conductive wire. Both ends of the tubular insulator are connected to the electrode fixing body and the tubular metallic housing respectively. A conductive wire passes through the tubular insulator and the tubular metallic housing, and is connected to an inner surface of the electrode fixing body. The electrode cap 11 disposed to cover an outer surface of the electrode fixing body. The ECP sensor with such a construction can lengthen the lifetime.

Abstract: A cathodic protection device having a sacrificial anode that is intended to wear out due to corrosion and that is electrically connected to a structure to be protected against corrosion. The cathodic protection device of the present invention further includes an indication device configured to detect and indicate the wear of the sacrificial anode wirelessly, without the use of cables.

Abstract: A sensor for measuring electrochemical corrosion potential includes an electrical conductor, a metal-oxide layer disposed on the electrical conductor, and a zirconia-containing layer disposed on the metal-oxide layer, wherein the zirconia-containing layer is disposed about the electrical conductor using thermal spraying, wire arc, ion plasma cathodic arc deposition, laser ablation, chemical vapor deposition, physical vapor deposition, electroplating, electroless plating, electrochemical oxidation, chemical oxidation, electrophoretic deposition, or radio-frequency sputtering.

Abstract: Electrochemical probes for corrosion monitoring in an environment that may cause the formation of electron-conducting deposits and the method for making such probes were described. The probes have long exposed electrodes. Except for the tip section, all surfaces of the exposed electrodes are coated with a coating or covered with electrically insulating tubing, so that only the tip section has uncovered metal that serves as the active areas of the electrodes. The coating or tubing material is such that the deposits cannot easily form on its surfaces. Because the electrical bridging between the active areas of any two electrodes requires the deposition of an evenly distributed layer of the electron-conducting deposits along the path from one area to the other area, the coated surface reduces the possibility of short-circuiting for the active areas of the electrodes. These probes are especially suitable for applications in systems containing hydrogen sulphide (H2S).

Abstract: Disclosed herein is an electrochemical corrosion sensor. The sensor may include an array of electrodes wherein each electrode may include a diamond like carbon coating disposed on at least a portion of the electrodes. The coating thickness may be at least about 1 micron. The electrodes may therefore provide relatively more accurate determination of electrode corrosion rates that may be more consistent with coupon type gravimetric testing.

Abstract: An electrochemical noise method, apparatus and system may be used to estimate and/or calculate parameters of interest related to corrosion rates of an electrically conductive article. The apparatus involves a working electrode (having substantially the same composition of the electrically conductive article), a reference electrode, and a counter electrode in an environment of interest. The working electrode is placed under potentiostatic control. A current transient between the working electrode and the counter electrode is measured. The working electrode is switched to open potential. A potential transient is measured over the duration of a localized corrosion event. The localized corrosion may then be calculated based on the measured potential transient and the current transient.

Abstract: A measuring device (1) for monitoring materials that affect corrosion of a steel reinforcement (2) in a concrete part (3) includes a sensor (4), which can be disposed inside the concrete part (3) in the vicinity of the steel reinforcement (2), and an external electronic evaluation device (5), which can be disposed outside the concrete part (3). At least two axially spaced-apart, wire-like probes (9, 9?), wrapped in loop-like fashion around the housing (6), are disposed on the outside of the housing wall (8) of the sensor (4), which probes have a different spacing from the steel reinforcement (2) to be monitored, so that the course over time of the corrosion progressing in the direction of the steel reinforcement (2) is ascertainable by the external electronic evaluation device (5).

Abstract: An electrochemical noise method, apparatus and system calculates parameters of interest related to corrosion rates of an electrically conductive article. The method involves placing a test electrode, a reference electrode, and an auxiliary electrode in an environment of interest; placing the test electrode under potentiostatic control regime for a potential scan; measuring the relationship of current v. potential (polarization resistance, Rp) of the test electrode relative to the reference electrode during a first period; switching from potentiostatic control to the open circuit potential (OCP) of the test electrode; monitoring the OCP of the test electrode during a second period; determining ?I from the relationship Rp=?V/?I, where ?V is measured over a second period of time; and calculating the localized corrosion from the measured potential and current data.

Abstract: Methods of deriving the cumulative maximum localized corrosion rate and cumulative localized corrosion rate factor for corrosion monitoring using coupled multielectrode array sensor probes are disclosed. Compared with maximum localized corrosion rate, which is derived from the corrosion rate on any of the electrodes of a probe that has the highest corrosion rate at a given moment of time, cumulative maximum localized corrosion rate is derived from the corrosion rate of the electrode that has been corroded the most in a given time period. The cumulative maximum localized corrosion rate is directly related to the corrosion damage (maximum localized corrosion depth); the maximum localized corrosion depth equals the integration of the cumulative maximum localized corrosion rate. Cumulative maximum localized corrosion rate should be used to evaluate the localized corrosion effect on metal damage.

Abstract: The bounding corrosion rate is measured with a coupled multielectrode array sensor by decoupling a select number of anodic electrodes on the sensor from the coupling joint. In doing so, all or most of the electrons produced on the anodic electrode that remains connected to the coupling joint are forced to flow to the coupling joint and are thus measured. Because of the large number of electrodes on a multielectrode array sensor, one of them may become contaminated by foreign materials during the measurements or polishing process. The effect of such an electrode on the performance of the sensor can be eliminated by automatically disconnecting it from the coupling joint.

Abstract: Systems and methods are presented for a method for measuring or monitoring localized corrosion in which an electrochemical noise (ECN) signal is sensed and filtered by a high-pass or band-pass filter to remove low frequency components not related to localized corrosion and a standard deviation of the filtered signal is computed and scaled to provide a localized corrosion value.

Abstract: Simultaneous determination of general corrosion and localized corrosion rate measurements is achieved with polarization applied by the electrodes themselves rather than externally applied polarization. Two or more working electrodes may be galvanically coupled. A localized pitting corrosion event on one of the electrodes will lead to a potential transient. The area within the potential transient is measured with the baseline being the initial starting potential. This gives localized corrosion as a function of time. The relationship Rp=?V/?I is calculated, where Rp is the polarization resistance of the working electrodes and is a measure of generalized corrosion rate.

Abstract: A method for determining a fatigue status of a growing crack in a substrate. An electrochemical sensor device is provided and includes an electrode formed from a stainless steel mesh. The electrochemical device has a bottom surface that contacts the substrate. The bottom surface is coated with an adhesive layer, and a release paper is attached to the adhesive layer. The release paper is separated from the adhesive layer, thereby exposing the adhesive layer. The electrochemical sensor device is secured to the substrate by bringing the adhesive layer in contact with the substrate and thereby forming an electrolyte cavity bounded in part by the substrate. The adhesive seals the bottom surface of the device to the substrate in order to prevent leakage of electrolyte from the cavity. The cavity is filled with the electrolyte.

Abstract: A localized corrosion monitoring (LCM) device is modified to obtain polarization resistance (Rp) from electrical resistance of a probe having a strip of metal under investigation (test electrode), a reference electrode and a temperature sensor (e.g. thermocouple). This configuration allows the probe to be used in areas where only a thin film of conductive fluid is available or required to provide potential monitoring. Thus, the applicability of the LCM technique is broadened. All the above devices are expected to be configured in one item of equipment, except for the probe which may be remotely located from the rest of the equipment.

Abstract: A system and method for the high temperature in-situ determination of corrosion characteristics of a molten metal on an alloy under study is provided which takes place within an insulated furnace. A graphite crucible provided in the furnace contains an electrolyte formed from a molten salt of a metal halide. A reference electrode formed from the same metal as the electrolyte is immersed in the electrolyte solution in the graphite crucible. A beta-alumina crucible containing a molten metal is also provided within the furnace and preferably within the graphite crucible. A measuring electrode formed from the alloy under study is immersed in the molten metal. Standard electrochemical techniques are used to measure and analyze the electrochemical effects of corrosion of the molten metal on the alloy.

Abstract: A method for processing a polymeric article, by introducing ingredients including a polymeric material for forming a polymeric article into an apparatus including a wall surface over which the polymeric material travels in at least a fluidic state, and an orifice through which the ingredients exit the apparatus. The ingredients are mixed while in the apparatus to form a polymeric ingredients mixture. A corrosion response of the wall surface of the apparatus is monitored with at least one resistance corrosion sensing probe that is flush mounted with the interior wall surface. The polymeric mixture is solidified after it exits the orifice for forming the polymeric article and mitigating corrosion detected by the monitoring step.

Abstract: The corrosion inhibiting activity of a coating is determined from the effect of corrosion inhibiting species released by the coating on the oxygen reduction current for a cathode placed very close to the coating. A rotating disk electrode or pumped solution flow is used to sweep the corrosion inhibiting species from the coating surface to the cathode. The oxygen reduction current is measured under conditions of oxygen diffusion control.

Abstract: A method and apparatus for cleaning a wafer with a metal exposed through an insulator, through the use of a wet cleaning tank in concert with a feedback system on the potential difference between two leads of the wet cleaning tank. The cleaning tank has a bath in which the wafer and the two leads are immersed. The potential difference between the two leads is regulated when the feedback system detects a change in the potential across the two leads.

Abstract: An electronic system and software program for multielectrode electrochemical devices; a multielectrode sensor for application in environments containing electrochemically active species; and a multielectrode sensor with a built-in removable large electrode. The electronic system has a large electrode connected to the coupling joint through a resistor element to adjust the potential of the multielectrodes. The electronic system, along with the software program, automatically changes the values of the coupling resistors so that the potentials of a group of electrodes or all the electrodes of a sensor are similar, or automatically disconnects malfunctioning electrodes from the coupling joints to avoid the effect of such electrodes. A variation of the electronic system uses an ammeter or a zero-resistance-ammeter to measure the coupling currents and has resistors between the electrodes and the coupling joint to reduce the transient current produced during switching.

Abstract: An electrochemical integrated system for measuring the galvanic current values and direction for two to four electrodes, comprising a corrosion cell and two to four electrodes coupled together via an interface and exposed to electrolyte for allowing electrochemical oxidation and reduction reactions to occur on the surface of the electrodes, characterized in that the two to four electrodes are flat metallic specimens made of different metals and alloys, and arranged adjacent and parallel to each other at the bottom of the corrosion cell so that the electrolyte is kept perpendicular on the flat specimens, with a non-corrosive material working as a barrier or isolator among them, wherein the whole combination of specimens is exposed to identical electrolytes under identical conditions allowing monitoring of the galvanic current values and directions at the same time for the whole combination.

Abstract: Disclosed herein is an electrochemical corrosion sensor. The sensor may include an array of electrodes wherein each electrode may include a diamond like carbon coating disposed on at least a portion of the electrodes. The coating thickness may be at least about 1 micron. The electrodes may therefore provide relatively more accurate determination of electrode corrosion rates that may be more consistent with coupon type gravimetric testing.

Abstract: The corrosion inhibiting activity of a coating is determined from the effect of corrosion inhibiting species released by the coating on the oxygen reduction current for a cathode placed very close to the coating. A rotating disk electrode or pumped solution flow is used to sweep the corrosion inhibiting species from the coating surface to the cathode. The oxygen reduction current is measured under conditions of oxygen diffusion control.

Abstract: A sensor for measuring electrochemical corrosion potential includes an electrical conductor, a metal-oxide layer disposed on the electrical conductor, and a zirconia-containing layer disposed on the metal-oxide layer, wherein the zirconia-containing layer is disposed about the electrical conductor using thermal spraying, wire arc, ion plasma cathodic arc deposition, laser ablation, chemical vapor deposition, physical vapor deposition, electroplating, electroless plating, electrochemical oxidation, chemical oxidation, electrophoretic deposition, or radio-frequency sputtering.

Abstract: A portable test station is disclosed in a unitary package that integrates a typical Copper-copper sulfate reference electrode with test apparatus. The electrode is maintained in a state of equilibrium by way of immersion in a liquid environment which prevents the solution contained within the electrode from leaching out of the electrode's porous end. This feature enables extended periods of reliable service not otherwise possible. The liquid environment also serves as a conductive bridge between the electrode's porous end and the installation site's environment. Continuity is achieved by way of an adjustable porous ceramic plug located in the base of the apparatus, which may be manipulated by the user prior to installation, i.e. water is allowed to leech from the apparatus into the environment through the exposed surface area of the ceramic plug which may be increased or decreased to suit a particular installation's need.

Abstract: A semi-permanent reference electrode for use in monitoring and measuring metals in field applications, such as cathodic protection. This electrode has an outer electrode body with a cap and porous plug. The outer electrode body is filled with a fill solution which is a saturated salt solution formed from a solid salt. The solid salt is hygroscopic with a low deliquescence point. An opening is provided in the cap to allow moisture into the outer electrode body to combine with the fill solution to maintain the saturated salt solution in the field. This saturated salt solution must maintain a constant pH for use in the semi-permanent reference electrode. A wire is used within the outer electrode body which connects to a voltmeter. This voltmeter measures the potential difference between the reference electrode and the field component of interest, which can include pipelines, storage tanks and bridges.

Abstract: The invention provides an electrochemical noise method, apparatus and system for estimating parameters of interest related to corrosion rates of an electrically conductive article, the method comprising: placing a working electrode, a reference electrode, and a counter electrode in an environment of interest; measuring potential at open circuit between the working electrode and the reference electrode over time; placing the working electrode under a potentiostatic control; measuring current between the working electrode and the counter electrode for a predetermined period of time, the period of time of measurements may be extended to include a transient event; and estimating the corrosion rate.

Abstract: A rotational test electrode assembly for use in a corrosive fluid environment as shown in FIG. 1 that includes a generally cylindrical heat and electrically conductive member (110) having an annular portion (112) and a solid portion (114): a heating device (130) positioned inside of the annular portion and in heat exchanging relation with the solid portion of the conductive member; a corrosion resistant external protective member (140) that surrounds a portion of the heat conductive member in close-fitting relationship; mounting means for attaching a rotational electrode (150) in close fitting heat and electrically conductive relation, the electrode being selected from the group consisting of cylindrical and disk electrodes; and an electrical connector for receiving a plurality of external electrical connectors that is mounted on the protective member opposite the portion of the conductive member on which the rotational electrode is mounted.

Abstract: A method of measuring localized corrosion, using a multi-electrode array sensor. The method eliminates the effect of internal current in corroded electrodes, and thus provides a more accurate corrosion measurement. In one embodiment, the potential of a common node of the sensor is adjusted so that the sensor's most cathodic current is close to zero.

Abstract: Low power corrosion measurement devices are described with improved LPR, HDA, and ECN measurement capabilities in a field transmitter for online corrosion monitoring or off-line corrosion data logging.

Abstract: Low power corrosion measurement devices are described with improved signal measurement and excitation circuitry in a field transmitter for online corrosion monitoring or off-line corrosion data logging.

Abstract: Corrosion measurement devices are described with electrical isolation and intrinsic safety barriers advanced corrosion measurement in a field transmitter for online corrosion monitoring or off-line corrosion data logging.

Abstract: Provided is an apparatus for concurrently detecting a defect occurring in a heat exchanger tube and a geometric transition of the heat exchanger tube. The apparatus for detecting the state of a heat exchanger tube, including: the first detection unit detecting a defect of the heat exchanger tube; and the second detection unit detecting a geometric transition of the heat exchanger tube, in which the first detection unit and the second detection unit are disposed at the same circumferential position of a cylindrical body separately, installed to have a certain distance in the lengthwise direction of the cylindrical body, and inserted inside the heat exchanger tube. According to the present invention, not only a defect but also the type of geometric transition, which may accelerate the initiation and growth of a defect, is identified and the size of the geometric transition is concurrently measured, thereby improving the reliability in early detection of a defect.

Abstract: Low power corrosion measurement devices are described with programmable configuration for implementing one or more advanced corrosion measurement types to provide conductivity, general corrosion, and/or localized corrosion values in a field transmitter for online corrosion monitoring or off-line corrosion data logging.

Abstract: A method and test apparatus for carrying out testing on a variety of samples of polymer bonded to metal wherein the samples are subjected to an accelerated cathodic reaction causing cathodic delamination of the samples. In particular, the method and test apparatus include a closed vessel that is partially filled with synthetic ocean water. An impressed current system is employed to protect the metal component of the samples. The synthetic ocean water is heated with an external band heater raising the temperature of the synthetic ocean water to thermal levels exceeding normal ocean temperatures in order to accelerate the reaction. Pure oxygen is then introduced into the closed vessel at a desired pressure to dissolve the oxygen into the synthetic ocean water to further simulate natural ocean conditions.

Abstract: A sensor including at least one electrode (3, 4) which is made of electrically conductive plastic and is connected to one end of an electrical conductor (5, 6). The electrode (3, 4) and conductor (5, 6) are surrounded by an insulating housing (2, 22), except that the electrode has an exposed surface (7, 8) for contacting an aggressive or corrosive medium inside the housing. The other end (11, 12) of the electrical conductor protrudes from the housing (2, 22). The housing (2, 22) is made of an electrically insulating plastic material which is joined to the electrode (3, 4) in a sealed manner. In a preferred embodiment, the housing (2, 22) forms a valve seat and seal for a bottom drain valve of a fluid container.

Abstract: Techniques are provided for measuring chloride ion concentration in a medium. The techniques allow measurements to be made in dry or alkaline media, or both. For alkaline conditions, a sensor includes a pair of electrodes and a polymer film imprinted for uptake of chloride ions under alkaline conditions. The film is deposited to be in contact with at least one electrode and the medium. For dry conditions, a sensor includes a pair of electrodes and a conductive polymer film imprinted for uptake of chloride ions. The film is in contact with the pair of electrodes, and is positioned for contact with the medium. An electrical conductivity of the film depends on an amount of chloride ions taken up by the film. Some techniques allow chloride ion measurements over years at sensors embedded in concrete. Such measurements allow the determination of the progress of rebar corrosion in concrete infrastructure.

Abstract: A system for monitoring corrosion in metal by comparing a test sample exposed to a corrosion causing environment and a reference sample exposed to a protected environment. An AC voltage source generates a square wave signal oscillating between ground and voltage Vcc and a filter is positioned to filter the signal to produce a sine wave with no second harmonic component. A voltage-driven current source and inverting amplifier produce a current referenced to 0.5 Vcc to provide an AC current from the drive voltage driven sinusoidally and symmetrically above and below 0.5 Vcc. A transformer steps up the AC current and thereafter transmits the current through the samples to an amplifier for amplifying the current to provide outputs in a ratio representing the degree of corrosion of the reference sample. The system can operate in situ for on site measurement and uses relatively low current to permit long operation.

Abstract: A method of measuring an electrochemical corrosion potential (ECP) of a material specimen using a detecting device including an ECP detecting array is provided. The method includes locating an offset spacer in close contact to a face of the ECP detecting array, locating the material specimen within the detecting device with a measurement face in close contact to the offset spacer, establishing a flow through the detecting device, and measuring an electrical potential between the detecting device ground and an electrode wire.

Abstract: A system comprises a first conductor configured to receive a signal via a supply side gas pipe, a second conductor configured to receive a reference signal via a reference path, and a circuit coupled to the first conductor and the second conductor. The circuit is configured to receive the signal and the reference signal to provide power to the system.

Abstract: The invention concerns a sensor and a method for detecting microbiologically induced corrosion in a metal structure, which consists in performing the following steps: providing a sensor comprising at least a first circular electrode (4) and a ring-shaped electrode (2) concentric with the first electrode, proximate to the structure (30) in contact with a corrosive medium; imparting for a time interval t a conditioning current between the two electrodes so as to initiate corrosion, the current being such that the central electrode is cathode and the ring-shaped electrode is anode; after the time interval t, coupling the two electrodes and measuring the current between the two electrodes; calculating the speed of corrosion from the measurement.

Abstract: The present invention relates to a method and an apparatus for measuring accumulated and instant rate of material loss or material gain of metal elements for the detection of metal deposition (material gain) caused for example during deposition of coatings used in plating processes and corrosion (material loss) caused for example in pipelines during transportation of hazardous media. The apparatus and the method provides means for measuring accumulated and instant rate of material loss or material gain by inserting a probe in a measurement environment causing a probe experience metal deposition or corrosion. Further the apparatus and the method provides means for performing a temperature independent measurement of accumulated and instant rate of material loss or material gain accomplished without use of a temperature sensor device.

Abstract: An apparatus for indicating when a predetermined portion of a sacrificial anode has been corroded comprises a detector embedded within the interior of the sacrificial anode initially at a predetermined distance from an exposed exterior surface of the sacrificial anode. The detector detects the absence of sacrificial anode material when the predetermined portion has corroded and generates a detection signal. A monitoring system communicates with the detector for receiving detection signals and generates an indicator signal when a detection signal is received. An indicator in communication with the monitoring system receives indicator signals and generates an alarm when an indicator signal is received.

Abstract: A system using tank corrosion sensors to provide for an overall assessment and monitoring of the electro-chemical corrosion and coatings condition in ships' tanks, and particularly in ships' seawater or compensated fuel tanks. The system includes reference half-cells mounted along a suspended cable and one instrumented sacrificial anode at the end of the cable to provide optimal sensing capability within a tank structure. The reference half-cells and the sacrificial anode measure a potential and current output, respectively. Together the measurements provide objective information that can be used to predict corrosion damage and coating deterioration occurring throughout the structure of the tank. The system may be used for an overall assessment and monitoring of the electrochemical corrosion and coatings condition. In a preferred embodiment, the measurements are stored in a datalogger that is optimally contained within an associated instrument housing.