ASTM_G_119_-_09.pdf

Designation:G11909Standard Guide forDetermining Synergism Between Wear and Corrosion1This standard is issued under the fixed designation G119;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide covers and provides a means for computingthe increased wear loss rate attributed to synergism or interac-tion that may occur in a system when both wear and corrosionprocesses coexist.The guide applies to systems in liquidsolutions or slurries and does not include processes in agas/solid system.1.2 This guide applies to metallic materials and can be usedin a generic sense with a number of wear/corrosion tests.It isnot restricted to use with approved ASTM test methods.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2G3 Practice for Conventions Applicable to ElectrochemicalMeasurements in Corrosion TestingG5 Reference Test Method for Making Potentiostatic andPotentiodynamic Anodic Polarization MeasurementsG15 Terminology Relating to Corrosion and Corrosion Test-ing(Withdrawn 2010)3G40 Terminology Relating to Wear and ErosionG59 Test Method for Conducting Potentiodynamic Polariza-tion Resistance MeasurementsG102 Practice for Calculation of Corrosion Rates and Re-lated Information from Electrochemical Measurements3.Terminology3.1 DefinitionsFor general definitions relating to corro-sion see Terminology G15.For definitions relating to wear seeTerminology G40.3.2 Definitions of Terms Specific to This Standard:3.2.1 cathodic protection current density,icpthe electricalcurrent density needed during the wear/corrosion experiment tomaintain the specimen at a potential which is one volt cathodicto the open circuit potential.3.2.2 corrosion current density,icorthe corrosion currentdensity measured by electrochemical techniques,as describedin Practice G102.3.2.3 electrochemical corrosion rate,Cthe electrochemi-cal corrosion rate as determined by Practice G59 and convertedto a penetration rate in accordance with Practice G102.Thispenetration rate is equivalent to the volume loss rate per area.The term Cwis the electrochemical corrosion rate during thecorrosive wear process,and the term C0designates the elec-trochemical corrosion rate when no mechanical wear is al-lowed to take place.3.2.4 mechanical wear rate,W0the rate of material lossfrom a specimen when the electrochemical corrosion rate hasbeen eliminated by cathodic protection during the wear test.3.2.5 total material loss rate,Tthe rate of material lossfrom a specimen exposed to the specified conditions,includingcontributions from mechanical wear,corrosion,and interac-tions between these two.3.2.6 wear/corrosion interactionthe change in materialwastage resulting from the interaction between wear andcorrosion,that is,T minus W0and C0.This can be sub-dividedinto DCw,the change of the electrochemical corrosion rate dueto wear and D Wc,the change in mechanical wear due tocorrosion.4.Summary of Guide4.1 A wear test is carried out under the test conditions ofinterest and T is measured.4.2 Additional experiments are conducted to isolate themechanical and corrosion components of the corrosive wearprocess.These are as follows:4.2.1 Arepeat of the experiment in 4.1 with measurement ofCw,1This guide is under the jurisdiction of ASTM Committee G02 on Wear andErosion and is the direct responsibility of Subcommittee G02.40 on Non-AbrasiveWear.Current edition approved July 15,2009.Published August 2009.Originallyapproved in 1993.Last previous edition approved in 2004 as G11904.DOI:10.1520/G0119-09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2.2 A test identical to the initial experiment in 4.1,exceptthat cathodic protection is used to obtain W0,and4.2.3 Measurement of C0,the corrosion rate in the absenceof mechanical wear.4.3 DCwand DWcare calculated from the values measuredin the experiments described in 4.1 and 4.2.5.Significance and Use5.1 Wear and corrosion can involve a number of mechanicaland chemical processes.The combined action of these pro-cesses can result in significant mutual interaction beyond theindividual contributions of mechanical wear and corrosion(1-5).4This intera