ASTM_D_4048_-_10.pdf

Designation:D404810Standard Test Method forDetection of Copper Corrosion from Lubricating Grease1This standard is issued under the fixed designation D4048;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.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1 This test method covers the detection of the corrosive-ness to copper of lubricating grease.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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 heal practices and determine the applicabilityof regulatory limitations prior to use.For specific warningstatements,see Sections 7,8,and 10.2.Referenced Documents2.1 ASTM Standards:2D97 Test Method for Pour Point of Petroleum ProductsD130 Test Method for Corrosiveness to Copper from Petro-leum Products by Copper Strip TestD2500 Test Method for Cloud Point of Petroleum ProductsD4175 Terminology Relating to Petroleum,Petroleum Prod-ucts,and Lubricants2.2 ASTM Adjuncts:Copper Strip Corrosion Standard33.Terminology3.1 DefinitionsSee Terminology D4175.3.2 copper corrosion,neffect of a chemical attack oncopper metal by a lubricant causing various levels of tarnishingand change in appearance.3.2.1 DiscussionAcidic and other aggressive species,of-ten sulfur-based,in a lubricant can attack copper or copperalloys present in bearings or other lubricated surfaces.Thepresence of this antagonistic interaction is often apparent in awell-defined series of color changes.3.3 lubricant,nany material interposed between two sur-faces that reduces the friction or wear between them.3.4 lubricating grease,na semi-fluid to solid product of adispersion of a thickener in a liquid lubricant.3.4.1 DiscussionThe dispersion of the thickener forms atwo-phase system and immobilizes the liquid lubricant bysurface tension and other physical forces.Other ingredients arecommonly included to impart special properties.4.Summary of Test Method4.1 A prepared copper strip is totally immersed in a sampleof grease and heated in an oven or liquid bath at a specifiedtemperature for a definite period of time.Commonly usedconditions are 100 6 1C(212 6 2F)for 24 h 6 5 min.At theend of this heating period,the strip is removed,washed,andcompared with the Copper Strip Corrosion Standard.5.Significance and Use5.1 This test method measures the tendency of lubricatinggrease to corrode copper under specific static conditions.Itmay be of some value in predicting possible chemical attack onlubricated parts,such as bearings that contain copper or copperalloys.Such corrosion,for example,can cause prematurebearing failures.However,no correlations with actual fieldservice,most of which are under dynamic conditions,havebeen established.It does not measure either the ability of thelubricant to inhibit copper corrosion caused by factors otherthan the lubricant itself nor does it measure the stability of thegrease in the presence of copper.NOTE1Because this test method requires the ability to determinesubtle differences in color of copper strips,persons with certain types ofcolor blindness may find it difficult to accurately comparre a test strip tothe Copper Strip Corrosion Standard.6.Apparatus6.1 Test JarsCloud and pour jars,cylindrical jars of clearglass with flat bottoms,30 mm to 33.5-mm(1316in.to 1516in.)1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.G0.01 on Chemical and General Laboratory Tests.Current edition approved May 1,2010.Published July 2010.Originallypublished in 1981.Last previous edition approved in 2008 as D404802(2008).DOI:10.1520/D4048-10.2For 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.3Available from ASTM International Headquarters.Order Adjunct No.ADJD0130.Originally produced in 1973.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 inside diameter,and 115 mm to 125 mm(412in.to 5 in.)inheight as described in Test Methods D97 and D2500.6.2 Test Jar CoversBeakers,50-mL;borosilicate glass,approximately 40 mm(1.6 in.)by 50 mm(2.0 in.)suitable forcovering individual test jars.Small porcelain or glazed silicacrucibles or crucible covers or watch glasses or vented corksthat lightly cover the test jars,allowing pressure equalizationbetween the inside and outside of the jars,yet mi