1、Designation: D 2943 02 (Reapproved 2007)Standard Test Method forAluminum Scratch of 1,1,1-Trichloroethane to DetermineStability1This standard is issued under the fixed designation D 2943; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This is a screening test method to determine if sufficientinhibitors are present in 1,1,1-trichloroe
3、thane to provide atleast minimal stability in the presence of aluminum.1.2 Solvent passing this test method may not be stable forall applications.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 stan
4、dard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. A specific hazardstatement is given in Section 6.2. Summary of Test Method2.1 A cleaned, degreased, dry metal coupon of aluminumalloy is immersed in inhibited 1,1,1-tri
5、chloroethane andscratched while in the solvent. After sufficient time has elapsedto allow any reaction to occur, the presence or absence ofbubbling, solvent discoloration, or dark resinous material isnoted. The 1,1,1-trichloroethane is sufficiently inhibited only ifnone of these conditions is observ
6、ed.3. Significance and Use3.1 The degradation of insufficiently stabilized 1,1,1-trichloroethane, in the presence of aluminum, results in theformation of hydrochloric acid and polymeric residue. Thus, ifsuch degradation is allowed to continue, the aluminum will becorroded and the 1,1,1-trichloroetha
7、ne rendered unusable. Thepresence of free water invalidates this test method.3.2 This test method can be used to determine if 1,1,1-trichloroethane is sufficiently stabilized to inhibit reaction withaluminum or aluminum alloys. Solvent passing this testmethod still may not be stable for all applicat
8、ions. Consult aproducer for use applications.3.3 Aluminum should not be used as a material of construc-tion for pumps, tanks, pipelines, valves, spray equipment, orother handling equipment used for chlorinated solvents. Prop-erly stabilized halogenated solvents are, however, commonlyused in cleaning
9、 aluminum and other sensitive metals.4. Apparatus4.1 Aluminum Sheet Metal, designated ASTM Alloy 1100(UNS No. A91100),20.016 to 0.040 in. (0.4 to 1 mm) thick.4.2 Mild Steel Metal Object, such as an ice pick sharpenedto lead pencil-sized point.5. Preparation of Aluminum Coupon5.1 Degrease an aluminum
10、 coupon, 1 by 1 in., (2.5 by 2.5cm) by rinsing in a commercial grade of solvent such asperchloroethylene, trichloroethylene, or 1,1,1-trichloroethane.Hand-sand both sides of the aluminum coupon lightly with afine emery cloth, and rinse the coupon again. The surfaceshould be bright and free of haze.6
11、. Hazards6.1 This test method should be performed in a fume hood.Insufficiently inhibited solvent can react with aluminum toform hydrogen and hydrogen chloride gases. Solvent vaporsare also present. Their release to the atmosphere must beminimized.7. Procedure7.1 Conduct this test method at room tem
12、perature. Measure50 mL of inhibited 1,1,1-trichloroethane into a clean solvent-rinsed glass beaker. Place a freshly prepared aluminum couponin the solvent sample in a horizontal position on the bottom ofthe beaker. Scratch (Note 1) the top surface of the submergedaluminum coupon with a sharply point
13、ed mild steel instrument.Make three scratches approximately equally spaced and 0.005in. (0.1 mm) deep in one direction. Then make three additionalscratches at right angles to the original three (Note 2). Observethe aluminum coupon after 10 min and again after1hhaselapsed. In the event that continued
14、 decomposition occurs after1 h, add water to stop the reaction, remove the aluminumcoupon, and discard the solvent in a solvent container toprevent evaporation.1This test method is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the di
15、rectresponsibility of Subcommittee D26.04 on Test Methods.Current edition approved Feb. 1, 2007. Published March 2007. Originallyapproved in 1971 as D 2943 71 T. Last previous edition approved in 2002 asD 2943 02.2Annual Book of ASTM Standards, Vol 02.02.1Copyright ASTM International, 100 Barr Harbo
16、r Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1The scratch should be a lateral scrape rather than a verticalperforation.NOTE 2Scratches are to appear as follows:8. Report8.1 For each test method, report observations as follows:8.1.1 Passes/no reaction.8.1.2 Fails/the app
17、earance of gas bubbles, color formation,or metal corrosion at the edge of the scratch marks are evidenceof failure to pass the test method.8.2 The solvent should be considered sufficiently stabilizedfor many uses in the presence of aluminum or aluminum alloysonly if no reaction occurs. The absence o
18、f reactivity in this testmethod may not indicate stability for all applications.9. Precision and Bias9.1 Only visual observations are reported. No precision andbias statements can be made.10. Keywords10.1 aluminum; aluminum scratch test; inhibitors; stabilitytest;1,1,1-trichloroethaneASTM Internatio
19、nal takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their
20、 own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be
21、 addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards
22、, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 2943 02 (2007)2
