ASTM_B_600_-_11_2017.pdf

Designation:B60011(Reapproved 2017)Standard Guide forDescaling and Cleaning Titanium and Titanium AlloySurfaces1This standard is issued under the fixed designation B600;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 U.S.Department of Defense.1.Scope1.1 This guide covers a cleaning and descaling procedureuseful to producers,users,and fabricators of titanium andtitanium alloys for the removal of ordinary shop soils,oxides,and scales resulting from heat treatment operations and foreignsubstances present as surface contaminants.1.2 It is not intended that these procedures be mandatory forremoval of any of the indicated soils but rather serve as a guidewhen titanium and titanium alloys are being processed in thewrought,cast,or fabricated form.1.3 It is the intent that these soils be removed prior tochemical milling,joining,plating,fabrication,and in anysituation where foreign substances interfere with the corrosionresistance,stability,and quality of the finished product.1.4 Acid etching may be required following cleaning whenthe surface has an oxygen-contaminated layer or alpha casepresent.1.5 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to consult and establish appropriatesafety and health practices and determine the applicability ofregulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Processing Soil Removal2.1 It is recommended that grease,oil,and lubricantsemployed in machining,forming,and fabricating operations ontitanium and titanium alloys be removed by alkaline oremulsion soak-type cleaners and electrolytic alkaline cleaningsystems.In the electrolytic system the work may be eitheranodic or cathodic polarity.Removal of these soils is recom-mended prior to heat treatment or application of acid treatmentdesignated in 4.2.When electrolytic systems are employed,thevoltage should be controlled to prevent the occurrence of sparkdischarge and subsequent pitting.3.Blast Cleaning3.1 Mechanical descaling methods such as sandblasting,shot blasting,and vapor blasting may be used to remove hotwork scales and lubricants from titanium surfaces if followedby thorough conditioning and cleaning as described in Section4.3.2 The sand used for blasting should be a high-grade,washed,iron-free,silica sand.If carbon or low-alloy steelproducts are sandblasted in the same facility,the sand used forcleaning these products should not be used on titanium surfacesand a separate sand supply should be provided.3.3 Roughening of exposed surface areas may occur fromgrit or shot if cleaning of the entire surface is accomplished byblasting.Partial cleaning for preserving the surface finish is tobe preferred in conjunction with proper pickling procedures.3.4 Blast cleaning that utilizes steel grit,steel shot,or sandcontaining appreciable amounts of iron should be followed byacid pickling to remove any embedded steel particles on thesurface of the titanium.3.5 Any abrasive or shot blast cleaning may induce residualcompressive stresses in the surface of the material or titaniumstructure.Warpage may occur in sections that are subsequentlychemical milled or contour machined.3.6 In most cases,blast cleaning is not intended to eliminatepickling procedures completely.Abrasives will not removesurface layers contaminated with interstitial elements such ascarbon,oxygen,and nitrogen.When these elements are present1This guide is under the jurisdiction of ASTM Committee B10 on Reactive andRefractory Metals and Alloys and is the direct responsibility of SubcommitteeB10.01 on Titanium.Current edition approved May 1,2017.Published May 2017.Originallyapproved in 1974.Last previous edition approved in 2011 as B600 11.DOI:10.1520/B0600-11R17.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee