Potentiostatic and potentiodynamic anodic

A detailed and well-referenced account of electrochemical methods of testing has been written by Dean, France and Ketcham in a section of the book by Ailor. ASTM G5 1987 outlines standard methods for making potentiostatic and potentiodynamic anodic polarisation measurements and ASTM G3 1974 (R1981) gives conventions applicable to electrochemical measurements in corrosion testing. 

Standard reference test method for making potentiostatic and potentiodynamic anodic polarisation measurements Recommended practice for atmospheric environmental exposure testing of nonmetal-lic materials... 

An ASTM recommended practice (A Standard Reference Method for Making Potentiostatic and Potentiodynamic Anodic Polarisation Measurements, G5 1972) has been issued. It provides a means of checking experimental technique and instrumentation using a specimen from a single heat of AISI Type 430 stainless steel, which is available from ASTM. ... 

Standard Reference Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements", ASTM G5-72. "Evaluating Degree of Rusting on Painted Steel Surfaces", ASTM D610-68. 

Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements, G 5-94, Annual Book ofASTMStandards, Vol 03.02, ASTM, 1995, p 48-58... 

Standard test procedures are defined within ASTM standards ASTM G 59, Practice for Conducting Potentiodynamic Polarization Resistance Measurements G 5, "Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements G 106, Practice for Verification of Algorithm and Equipment for Electrochemical Impedance Measurements and G 102, Practice for Calculation of Corrosion Rates and Related Information from Electrochemical Measurements. Each of these methods describes a standard procedure or practice for the test method. A complete discussion of the technologies is beyond the scope of the current text. For the current text, the focus is on the application of the most simple and most widely used of these techniques, the polarization resistance measurement, ASTM G 59. The parameters discussed are, however, applicable concerns for all electrochemical tests. 

ASTM G5— Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements... 

These standard methods and practices provide the necessary information for electrochemical potentiostatic and potentiodynamic anodic measurements, calculation of corrosion rate from electrochemical measurements, and conducting potentiodynamic polarization resistance measurements. Recently, Electrochemical Impedance Spectroscopy (EIS) htts been introduced for corrosion measurements of steel structures corroding in soils. These tests can be... 

Immersion testing wiU generate weight loss data, or corrosion current measurements can be obtained from stan-deird electrochemical polarization tests (see ASTM G 5, Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements see also Ref 27). Corrosion rates in millimeters per year (mpy) for titanium alloys can be calculated from sample weight loss data as follows ... 

Other DC methods that are quite simple to use and provide important information to the corrosion scientist include polarization resistance (ASTM G 59, Practice for Conducting Potentiodynamic Polarization Resistance Measurements), potentiostatic and potentiodynamic polarization measurements (ASTM G 5, Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements), cyclic polarization measurements (ASTM G 61, Test Method for Conducting Cyclic Potentiodynamic Polarization Measurements for Localized Corrosion Susceptibility of Iron-, Nickel-, or Cobalt-based Alloys), and galvanic current monitoring. These DC techniques can be used to estimate the reactivity of a mateiieJ in a peurticular environment, to determine the corrosion rate of a materieJ in a particular environment, and/or to determine the susceptibility of a material to localized corrosion. 

Cyclic anodic polarization procedures based upon ASTM G5 (Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements) have been used to evaluate the localized corrosion resistance of stainless steel alloys in paper machine white waters. The difference between the open circuit or naturally occurring corrosion potential and the pitting breakdown potential of various materials has been reported by many investigators [lO-Id]. Bowers [14] called the difference between the breakdown potential and the potential of the cathodic/anodic current reversal the margin of safety. He also noted the effect of the sulfate to chloride concentration ratio on localized corrosion of Types 304 and 316L stainless steels, These results permitted alternative materials of construction to be ranked and their limits of resistance to be defined. 

ASTM G 3 (Practice for Conventions Applicable to Electrochemical Measurements in Corrosion Testing) [74] and Refs 49, 55, and 73 show the schematics for the apparatus for corrosion measurements and schematic drawings for cathodic and anodic polarization diagrams and polarization plots. ASTM G 5 (Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements) [74] and ASTM F 4 [55] test methods and practices describe the setup and procedures for making potentiostatic and potentiodynamic anodic polarization measurements. A cyclic polarization curve that contains both the cathodic and anodic portions provides data that can be used to describe corrosion behavior in terms of passivity, breakdown, corrosion rate, and susceptibility to pitting. 

Potentiostatic and potentiodynamic anodic polarization measurements often are applied to medical and dental materials, and test methods in ASTM G 5 and ASTM F 4 can be used as guides along with published literature. These methods involve applying a potential to the specimen and... 

Potentiostatic and Potentiodynamic Anodic Polarization Measurements and ASTM G106 - 89 Standard Practice for Verification of Algorithm and Equipment for Electrochemical Impedance Measurements. Although most ASTM electrochemical testing techniques are developed for stainless steels, the test methods and procedures can be adapted for noble metals used in implantable medieal devices. 

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