1、Designation: D7935/D7935M 14Standard Test Method forCorrosion Test for Non-Aqueous Engine Coolants inGlassware1This standard is issued under the fixed designation D7935/D7935M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a simple beaker-type procedurefor evaluating the effects of non-aqueous engine coolants
3、onmetal specimens under controlled laboratory conditions (seeAppendix X1).NOTE 1For more information on aqueous and non-aqueous enginecoolants, see (Refs 1-9).21.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may n
4、ot be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard. Some values have only SI units because theinch-pound equivalents are not used in practice.1.3 This standard does not purport t
5、o 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. Some specifichazards statements are given in 10.1.
6、7.2, 10.1.7.3, and 10.1.7.4.2. Referenced Documents2.1 ASTM Standards:3B32 Specification for Solder MetalB36/B36M Specification for Brass Plate, Sheet, Strip, AndRolled BarD1176 Practice for Sampling and Preparing Aqueous Solu-tions of Engine Coolants or Antirusts for Testing PurposesD1384 Test Meth
7、od for Corrosion Test for Engine Coolantsin GlasswareE1 Specification for ASTM Liquid-in-Glass ThermometersE178 Practice for Dealing With Outlying ObservationsE230/E230M Specification and Temperature-ElectromotiveForce (emf) Tables for Standardized Thermocouples2.2 ASTM Adjunct:4All-glass apparatus
8、for corrosion test (2 drawings)3. Summary of Test Method3.1 In this test method, specimens of metals typical of thosepresent in engine cooling systems are totally immersed inaerated engine coolant solutions for 336 h at 96C 205F. Thecorrosion-inhibitive properties of the test solution are evaluatedo
9、n the basis of the weight changes incurred by the specimens.Each test is run in triplicate, and the average weight change isdetermined for each metal. A single test may occasionally becompletely out of line (see 11.3).4. Significance and Use4.1 This test method will generally distinguish betweennon-
10、aqueous coolants that are definitely deleterious from thecorrosion standpoint and those that are suitable for furtherevaluation. However, the results of this test method cannotstand alone as evidence of satisfactory corrosion inhibition.The actual service value of an engine coolant formulation canbe
11、 determined only by more comprehensive bench,dynamometer, and field tests.5. Apparatus5.1 Container, a 1000-mL, tall-form, spoutless beaker, madeof heat-resistant glass, for containing the non-aqueous enginecoolant solution and test specimens. The beaker shall be tightlyclosed with a No. 15 rubber s
12、topper, having drill holes toaccommodate a water condenser, an aerator tube, and atemperature measuring instrument as shown in Fig. 1.Optionally, an all-glass apparatus may be used.45.2 Condenser, a water condenser of the reflux, glass-tubetype, having a 400-mm 16-in. condenser jacket.1This test met
13、hod is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.22 on Non-Aqueous Coolants.Current edition approved June 1, 2014. Published August 2014. DOI: 10.1520/D7935_D7935M142The boldface numbers in parentheses refer
14、to the list of references at the end ofthis standard.3For 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.4Availab
15、le from ASTM International Headquarters. Order Adjunct No.ADJD1384. Original adjunct produced in 1980.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.3 Aerator Tube, a gas-dispersion tube, porosity size 12-C,5to ensure continuous ae
16、ration without plugging.5.4 Temperature Measuring Instrument (EnvironmentallySafe Thermometer or Thermocouple), anASTM Partial Immer-sion Temperature Measuring Instrument having a range from 20 to 150C 0 to 302F and conforming to the requirementsfor Thermometer 1C 1F, as prescribed in Specification
17、E1or Thermocouple as summarized in Specification E230/E230M.5.5 Heater, a constant-temperature bath containing a high-boiling liquid that is capable of giving continuous service withthe specified temperature control.6The size of the bath will bedetermined by the number of corrosion tests that are to
18、 be runconcurrently.6. Metal Test SpecimensNOTE 2The specimens prescribed in this test method have beenaccepted by automobile manufacturers, but their composition may not bethe same as that of alloys currently used for engine cooling systemcomponents. Therefore, specimens other than those designated
19、 in this testmethod may be used by mutual agreement of the parties involved.6.1 TypeThe following metal test specimens,7representa-tive of cooling system metals, shall be used:6.1.1 Steel, UNS G10200 (SAE 1020),8cut from 1.59-mm116-in. cold-rolled sheet stock to size 50.8 by 25.4 mm 2 by1 in. Chemic
20、al composition of the carbon steel is as follows:carbon, 0.17 to 0.23 %; manganese, 0.30 to 0.60 %;phosphorus, 0.040 % maximum; sulfur, 0.050 % maximum.6.1.2 Copper, conforming to UNS C11000 (SAE CA110)8or UNS C11300 (SAE CA113).8Cold-rolled, cut from1.59-mm 116-in. sheet stock to size 50.8 by 25.4
21、mm 2 by 1in.6.1.3 Brass, conforming to Alloy UNS C26000 (SAE CA260). Half-hard, cut from 1.59-mm 116-in. sheet stock to size50.8 by 25.4 mm 2 by 1 in.5The sole source of supply of the apparatus known to the committee at this timeis Corning Glass Works, 44-5 Crystal St., Corning, NY 14830. Gas-disper
22、sion tubeNo. 39533, manufactured by Corning Glass Works, has generally been foundsatisfactory for this purpose. Optionally, a capillary tip bleed tube with 7-mm0.28-in. bore and 280-mm 11.2-in. length may be used when consistent earlyplugging of gas dispersion tubes occurs. The tube, catalog No. 781
23、5-19, may beobtained from Corning Glass Works. If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful consideration at a meeting of the responsible technical committee,1which you may attend.6If a water bath is u
24、sed, a significant reduction in evaporation rate is achievedby addition of floating plastic chips on the water surface.7Complete sets or individual metal test specimens are available from (a)Chemical Specialties ManufacturersAssociation, Inc., Suite 1120, 1001 ConnecticutAve., N.W., Washington, DC 2
25、0036; (b) Astro-Mechanics, Inc., 8500 ResearchBlvd., Austin, TX 78766; (c) The Metaspec Company, P.O. Box 27707, SanAntonio, TX 78227; or (d) Metal Samples Co. Inc., P.O. Box 8, Munford,AL 36268.8Unified Numbering System for Metals and Alloys, SAE-ASTM, July 1995FIG. 1 Metal Specimens and Equipment
26、for 336h Corrosion TestD7935/D7935M 1426.1.4 SolderA brass specimen as described in 6.1.3,coated with solder conforming to Alloy Grade 30A (SAE 3A)of Specification B32. Solder-coated specimens may beprepared, or used specimens recoated for reuse, by the proce-dure given in Annex A1. A solid solder s
27、pecimen cut from1.59-mm 116-in. sheet stock ofAlloy Grade 30A(SAE 3A) tosize 50.8 by 25.4 mm 2 by 1 in. may be used subject tomutual agreement of the parties involved. The use of a solidsolder specimen must be reported along with the metalspecimen weight loss results.6.1.4.1 When agreed upon between
28、 the supplier and thepurchaser of engine coolants, the standard solder specimenmay be replaced with one having a different alloy compositionthan standardAlloy Grade 30Aor 30B. Use of specimens otherthan standardAlloy Grade 30Aor 30B shall be noted in the testreport.NOTE 3Where non-standard alloy is
29、used, the standard flux shown inA1.1.5 may not be satisfactory. A low corrosive flux may be required.6.1.5 Cast Aluminum, conforming to Alloy UNS A23190(SAE 329).8Specimen size, 50.8 by 25.4 by 3.18 mm 2 by 1by18 in.6.1.6 Cast Iron, conforming to Alloy UNS F10007 (SAEG3500).7Specimen size, 50.8 by 2
30、5.4 by 3.18 mm 2 by 1 by18 in.6.2 Arrangement (See Fig. 2):6.2.1 Metal Specimen ArrangementNone of the hardwareused in metal specimen arrangement (metal specimen, screws,washers, metal spacers, insulating sleeves, insulating spacersand nuts) can be reused for a test. The metal test specimensshall be
31、 drilled through the center with a 6.75-mm 1764-in.drill to accommodate a 50.8-mm 2-in. 1024 brass machinescrew covered with a thin-walled insulating sleeve. Polytetra-fluoroethylene tubing with a 6.35-mm 14-in. outside diameter1.59-mm 116-in. wide and a wall thickness of 0.4 mm164-in. is satisfacto
32、ry. Two half-hard brass legs shall be cutfrom 1.59-mm 116-in. sheet stock to size 50.8 by 25.4 mm 2by 1 in. A 6.35-mm 14-in. diameter hole shall be drilled ineach leg with the center 6.35 mm 14 in. from the top and 12.7mm 12 in. from each side. The test “bundle” shall be made upon the insulated scre
33、w with the specimens in the followingorder: brass leg, copper, solder, brass, steel, cast iron, castaluminum, and brass leg. The specimens shall be separated by4.76-mm 316-in. thick solid metal spacers having a 6.75-mm1764-in. inside diameter and a 11.11-mm 716-in. outsidediameter. Insulating spacer
34、s made from polytetrafluoroethyleneshall be used between the brass legs and the specimen“bundle,” and between the brass and steel specimens. Brassspacers shall be used between the brass, solder, and copperspecimens, and steel spacers between the cast iron, steel, andcast aluminum specimens. The nut
35、shall be tightened firmly toensure good electrical contact between the test specimens ineach section of the “bundle.”6.2.2 Alternate Metal Specimen ArrangementWhenagreed upon between the supplier and the purchaser, analternate metal specimen arrangement may be used to evaluatemultiple solder alloys,
36、 such as high lead Alloy Grade L50113consisting of 97 % lead, 2.5 % tin, 0.3 % silver, concurrentlywith StandardAlloy Grade 30Aor 30B. It is recommended thatthe metal specimen arrangement be modified by replacing thecopper specimen with the high lead solder specimen andarranging specimens in the bun
37、dle as follows:High Lead Brass Alloy Grade Steel Cast Iron CastSolder 30A or 30B AluminumUse of alternate specimens and metal specimens arrange-ments shall be noted in the test report.7. Preparation of Test Specimens7.1 Sand the cast iron and cast aluminum specimens on the25.4 by 50.8-mm 1 by 2-in.
38、cut surfaces with “coarse” grade(No. 1) emery cloth. Remove any burrs from coupon edges andhole. Scrub all specimens vigorously, using a moistened bristlebrush and ground pumice powder or fine silicon carbide grituntil the entire metal area is bright, shiny, and free from anyvisible oxide film or ta
39、rnish.7.2 Rinse the specimens thoroughly with tap water; thenrinse with acetone, dry, and weigh to the nearest 1 mg. CastFIG. 2 Metal Specimen ArrangementD7935/D7935M 143aluminum specimens should be dried in a 100C oven for 1 h,to a constant weight, prior to recording the weight.NOTE 4If the test sp
40、ecimens are not to be used immediately, keepthem in a desiccator until required.8. Test Solutions8.1 The concentration of the non-aqueous engine coolant tobe tested shall be as follows:8.1.1 Engine CoolantThe non-aqueous coolant shall bemixed with the proper quantity of corrosive water to give a tes
41、tsolution containing a mixture of 94 volume % non-aqueouscoolant with six volume % corrosive water.8.1.2 Corrosive Water (Note 5)The corrosive water shallcontain 100 ppm each of sulfate, chloride, and bicarbonate ionsintroduced as sodium salts.8.2 Preparation of SampleThe preparation of the samplesh
42、all be done in accordance with Test Method D1176, exceptthat the corrosive water shall be used for dilution instead ofdistilled water. Thus, any insoluble materials will be includedin the representative sample.NOTE 5The specified corrosive water can be prepared by dissolvingthe following amounts of
43、anhydrous sodium salts in a quantity of distilledor deionized water.sodium sulfate 148 mgsodium chloride 165 mgsodium bicarbonate 138 mgThe resulting corrosive water solution should be made up toa volume of 1 L with distilled or deionized water at 20C.8.2.1 If relatively large amounts of corrosive w
44、ater areneeded for testing, a concentrate may be prepared by dissolv-ing ten times the above amounts of the three chemicals, indistilled or deionized water, and adjusting the total volume to1 L by further additions of distilled or deionized water. Whenneeded, the water concentrate is diluted to the
45、ratio of one partby volume of concentrate to nine parts of distilled or deionizedwater.9. Test Conditions9.1 Beaker AssemblyThe arrangement of the assembledmetal specimens with relation to the aerator tube and othercomponents is shown in Fig. 1. Note that the tip of thecondenser just emerges from th
46、e bottom of the rubber stopper.9.2 Test TemperatureThe test solution shall be maintainedat a temperature of 96 6 2C 205 6 5F.9.3 Aeration RateThe aeration rate shall be 100 6 10mL/min. The aerator tube should be located at least 12.7 mm12 in. away from the test “bundle” to avoid direct contact witht
47、he metal specimens.9.4 Test DurationThe test shall be run continuously for 2weeks (336 h).10. Procedure10.1 Make triplicate tests concurrently on each enginecoolant solution in accordance with the following procedure:10.1.1 Carefully clean the test beaker, condenser, rubberstopper, and aerator tube,
48、 and thoroughly rinse with water.Ensure all components are dry before use.10.1.2 Bolt the specimens together in the order given in 6.2and place the “bundle” in the test beaker as shown in Fig. 1.10.1.3 Pour 750 mL of the prepared test solution into the1000-mL beaker.10.1.4 Fit the condenser and aera
49、tion tube to the beaker, andset the aeration rate at 100 mL/min, using a flow meter or othersuitable device.10.1.5 Raise the temperature of the test solution to 96C205F for high-boiling engine coolants. Pass water throughthe condenser at a rate sufficient to maintain adequate cooling.10.1.6 Check the tests once each working day to ensureproper solution temperature, aeration rate, and solution level.The tests may operate unattended on weekends and holidays.Make up
