1、Designation: D2512 17Standard Test Method forCompatibility of Materials with Liquid Oxygen (ImpactSensitivity Threshold and Pass-Fail Techniques)1This standard is issued under the fixed designation D2512; the number immediately following the designation indicates the year oforiginal adoption or, in
2、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.
3、1 This method2,3,4covers the determination of compatibil-ity and relative sensitivity of materials with liquid oxygenunder impact energy using the Army Ballistic Missile Agency(ABMA)-type impact tester. Materials that are impact-sensitivewith liquid oxygen are generally also sensitive to reaction by
4、other forms of energy in the presence of oxygen.1.2 This standard should be used to measure and describethe properties of materials, products, or assemblies in responseto heat and flame under controlled laboratory conditions andshould not be used to describe or appraise the fire hazard orfire risk o
5、f materials, products, or assemblies under actual fireconditions. However, results of this test may be used aselements of a fire risk assessment which takes into account allof the factors which are pertinent to an assessment of the firehazard of a particular end use.1.3 This standard does not purpor
6、t 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.1.4 This international standard was developed in
7、 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. Referenced Documents2.
8、1 ASTM Standards:5C145 Specification for Solid Load-Bearing Concrete Ma-sonry Units (Withdrawn 1992)6D1193 Specification for Reagent Water2.2 Military Standards:MIL-D-16791G Detergent, General Purpose (Liquid, Non-ionic)7MIL-P-27401C Propellant Pressurizing Agent, Nitrogen7MIL-PRF-25508F Propellant,
9、 Oxygen7MIL-T-27602B Trichloroethylene, Oxygen Propellant Com-patible8MIL-C-81302D Cleaning Compound, Solvent, Trichlorotri-fluorocarbon72.3 ASTM Adjuncts:Type Impact Tester and Anvil Region Assembly, 38 Draw-ings3. Summary of Test Method3.1 A sample of the test material is placed in a specimencup,
10、precooled and covered with liquid oxygen, and placed inthe cup holder located in the anvil region assembly of theimpact tester. A precooled striker pin is then centered in thecup. The plummet is dropped from selected heights onto thepin, which transmits the energy to the test specimen. Observa-tion
11、for any reaction is made and the liquid oxygen impactsensitivity of the test material is noted. Drop tests are continuedusing a fresh specimen cup and striker pin for each drop, until1This test method is under the jurisdiction of ASTM Committee G04 onCompatibility and Sensitivity of Materials in Oxy
12、gen Enriched Atmospheres and isthe direct responsibility of Subcommittee G04.01 on Test Methods.Current edition approved July 1, 2017. Published July 2017. Originally approvedin 1966. Last previous edition approved in 2002 as D2512 95 (2002)1which waswithdrawn January 2017 and reinstated in July 201
13、7. DOI: 10.1520/D2512-17.2NASA Handbook 8060. 1B, Ambient LOX Mechanical Impact Screening Test,September 1981, pp. 4-53 through 4-71. “Oxygen Systems.” George C. MarshallSpace Flight Center, National Aeronautics and Space Administration. SpecificationMSFC 106B. September 1981.3“Lubrication and Relat
14、ed Research and Test Method Development for AviationPropulsion Systems.” Technical Report No. 59-726. Wright Air DevelopmentDivision, January 1960.4“General Safety Precautions for Missile Liquid Propellants.”5For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custome
15、r Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.6The last approved version of this historical standard is referenced onwww.astm.org.7Available from Standardization Documents Order Desk, DODSSP, Bldg. 4
16、,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.8Cancelled in 1983. Previously available from Standardization DocumentsOrder Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA19111-5098, http:/dodssp.daps.dla.mil.Copyright ASTM International, 10
17、0 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 R
18、ecommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1the threshold valve is achieved. A series of drop tests areconducted at an energy level of 98 J (72 ftlbf) or as specifiedfor the pass-fail tests.4. Significance and Use4.1 When this test method is use
19、d to measure the thresholdimpact sensitivity of a material, a relative sensitivity assess-ment is obtained which permits the ranking of materials.4.2 This test method may also be used for acceptance-testing materials for use in liquid oxygen systems. Twentyseparate samples of the material submerged
20、in liquid oxygenare subjected to 98 J (72 ftlbf) or as specified. Impact energydelivered through a 12.7-mm (12-in.) diameter contact. Morethan one indication of sensitivity is cause for immediaterejection. A single explosion, flash, or other indication ofsensitivity during the initial series of 20 t
21、ests requires that anadditional 40 samples be tested without incident to ensureacceptability of the material.4.3 The threshold values are determined by this test methodat ambient pressure. The sensitivity of materials to mechanicalimpact is known to increase with increasing pressure. Sincemost liqui
22、d oxygen systems operate at pressures above ambientcondition, some consideration should be given to increasedsensitivity and reactivity of materials at higher pressure whenselecting materials for use in pressurized system.5. Apparatus5.1 ABMA-Type Impact Tester9(Fig. 1 , See ADJD2512),for determinin
23、g the sensitivity of materials to liquid oxygenwith impact energy. Fig. 2 shows the schematic diagram of thetypical power supply. The tester consists of the following parts:5.1.1 Three Guide Tracks, capable of maintaining accuratevertical alignment under repeated shock conditions.5.1.2 Plummet, with
24、 a weight of 9.072 6 0.023 kg (20 60.05 lbs).5.1.3 Safety Catch, operated by a solenoid, and designed tohold the plummet near the base of the magnet. It is used tosupport the plummet in the event of a power failure.5.1.4 Electromagnet, for supporting or releasing the plum-met. The electromagnet is d
25、esigned to hold 9.072 kg (20 lbs) ofweight with a minimum amount of electrical energy.5.1.5 BaseThe base of the tester is composed of thefollowing: a rigid 0.61- by 0.61- by 0.61-m (2- by 2- by 2-ft)(min) reinforced concrete block (concrete conforming to Speci-fication C145), a 3.2-mm (18-in.) stain
26、less steel sheet, and a25-mm (1-in.) thick stainless steel base plate. Four stainlesssteel foundation bolts protruding from the concrete block areused to fasten the plate and sheet to the smooth surface of theconcrete block with stainless steel nuts.NOTE 1Where not otherwise indicated, stainless ste
27、el shall be of theAISI 300 series.5.1.6 Anvil Plate (Fig. 3), made from a 51-mm (2-in.) thickType 440B heat-treated steel plate, (56 to 58 HRC) that iscentered and rests on the base plate. It in turn centers thespecimen cup holder.9Detailed drawings for the ABMA-Type Impact Tester and Anvil RegionAs
28、sembly are available from ASTM International Headquarters. Order AdjunctADJD2512.FIG. 1 ABMA-Type Impact Tester FIG. 2 Schematic Diagram of Power SupplyD2512 1725.1.7 Striker PinThe striker pins shall be machined fromAMS 5643D stainless steel, heat condition H-900 (Fig. 4).5.1.8 Striker Pin Guide.5.
29、1.9 Specimen CupsOne- and two-piece specimen cupsshall be used. The one-piece specimen cup (Fig. 5) shall beused for liquid and solid test materials. When testing hardsamples that are sometimes capable of initiating reactions withthe aluminum cup, expendable Type 347 stainless steel disks17.5 mm (11
30、16 in.) in diameter by 1.6 mm (116 in.) thick shallbe placed in the bottom of the cup. The two-piece cup (Fig. 6)shall be used for testing semisolid materials; a one-piece insertcup (Fig. 7) may also be used. The recess of either of thesepermits use of a 1.27-mm (0.050-in.) thick sample.5.1.10 Speci
31、men Cup Holder, consisting of a 25-mm (1-in.)thick stainless steel block centered on the anvil plate. Thisholder has two protruding spacers which align the striker pinguide, and in turn the striker pin, with the nose of the plummet,thus ensuring a direct hit by the nose of the plummet on thestriker
32、pin in the specimen cup.5.2 Test CellThe impact tester shall be housed in a test cellcontaining a concrete floor. Walls shall be constructed ofreinforced concrete or metal to provide protection from explo-sion or fire hazards. The cell shall be provided with ashatterproof observation window, and sha
33、ll be darkened suffi-ciently to permit observation of flashes. The operator shall belocated in a darkened area. Continuous ventilation shall pro-vide fresh air to the test cell. Construction of the cell shall bedirected at providing a facility that can be maintained economi-cally at a high level of
34、good housekeeping. The test cell shallbe cleaned periodically to ensure cleanliness of sample andequipment.5.3 Freezing Box, as illustrated in Fig. 8.5.4 Auxiliary EquipmentThe auxiliary equipment shallconsist of forceps for handling the specimen cups and strikerpins, stainless steel spatulas, liqui
35、d oxygen handling equipmentsuch as stainless steel Dewar flasks, liquid oxygen protectivegloves, lintless laboratory coat, eye protection equipment, andliquid oxygen storage containers. Special handling equipmentshall include striker pin holders (Fig. 9), specimen cup trays,covered storage container
36、 for specimen cups and striker pins,and a vapor-phase degreaser. The following items are alsorecommended: microburet, control panel with switches toactivate the safety catch and electromagnet, stereomicroscope,micrometer depth gage with leveling blocks, press punch cutterfor preparation of plastic s
37、pecimens, oven, and refrigerator. Forchecking surface roughness of striker pins and specimen cups,a set of visual roughness comparison standards10or a surfaceroughness measuring instrument shall be required. Timinginstrumentation shall be required to measure the drop time ofthe plummet. A suitable f
38、ree-fall timing circuit is illustrated inFig. 10.6. Reagents and Materials6.1 Alkaline Cleaner, for striker pins and stainless steelinserts, consisting of a solution of 15 g of sodium hydroxide(NaOH), 15 g of trisodium phosphate (Na3PO4), and 1 L ofdistilled or deionized water.6.2 Alkaline Cleaner,
39、for cups; a nonetch-type solution suchas Enthone NE11or equivalent shall be used.6.3 Aqua RegiaMix 18 parts of concentrated HNO3(sp gr1.42) with 82 parts of concentrated hydrochloric acid (HCl, spgr 1.19) by volume.6.4 Deionized Water, conforming to Specification D1193.6.5 Detergent, General-Purpose
40、 (Liquid, Nonionic), con-forming to MIL-D-16791G.10American National Standard B46.1-1962. Surface Texture standards may beused.11Available from Enthone, Inc., a division of American Smelting and RefiningCo., Box 1900, New Haven, CT 06508.FIG. 3 Anvil Region AssemblyNOTE 1Break sharp edges approximat
41、ely 0.015.NOTE 2Machine all surfaces 32 rums except as noted.NOTE 3Material: stainless steel AMS 5643 D.NOTE 4Heat treatment: H-900 to obtain Rc 43 to 44.NOTE 5Finish: electropolish after heat treatment.NOTE 6Surfaces A and B should be parallel and perpendicular to thecenter line within 0.001TIR and
42、 16-32 rms along a radius.All dimensions in inches.FIG. 4 Striker PinD2512 1736.6 Hydrofluoric Acid (48.0 to 51.0 %)Reagent gradeconcentrated hydrofluoric acid (HF).6.7 Liquid Nitrogen, conforming to MIL-P-27401C.(WarningContact with the skin can cause frostbites resem-bling burns.)6.8 Gaseous Nitro
43、gen, conforming to MIL-P-27401C.(WarningCompressed gas under high pressure. Always usea pressure regulator. Release regulator tension before openingcylinder.)6.9 Liquid Oxygen, conforming to MIL-PRF-25508F.(WarningOxygen vigorously accelerates combustion. Con-tact with skin can cause frostbite resem
44、bling burns.)6.10 Nitric Acid (relative density 1.42)Reagent gradenitric acid (HNO3).6.11 Trichloroethylene, conforming to MIL-T-27602.(WarningHarmful if inhaled. High concentrations maycause unconsciousness or death. Contact may cause skinirritation and dermatitis.)NOTE 2The use of trichloroethylen
45、e is banned in California by theCalifornia Air Pollution Board.6.12 Trichlorotrifluoroethane, conforming to MIL-C-81302D Type I. (WarningHarmful if inhaled.)7. Safety Precautions7.1 The hazards involved with liquid oxygen are veryserious. Contact with the skin can cause frostbites resemblingburns. C
46、ontact with hydrocarbons or other fuels causes anexplosion hazard, as such mixtures are usually shock, impact,and vibration-sensitive.7.2 The first-aid procedure for liquid oxygen contact is toflush the affected area with water. This treatment should befollowed by medical attention. A safety shower
47、must beavailable in the immediate area.7.3 The following safety rules must be observed: personnelworking with liquid oxygen must be familiar with its natureand characteristics. Approved goggles or face shields, protec-tive clothing, gloves, and boots must be worn during handlingor transfer. Such ope
48、rations shall be performed by not less thantwo persons as a group. Extreme caution shall be exercised inpreventing contact with oils or other combustible materials.Alltools must be degreased before use. Precautions shall be takento prevent accumulation of moisture in lines, valves, traps, andso fort
49、h to avert freezing and plugging with subsequentpressure ruptures. Care shall also be taken to prevent entrap-ment of liquid oxygen in unvented sections of any system.NOTE 1Break sharp edges 0.015.NOTE 2The cup is formed by deep drawing.NOTE 3The thickness and parallelness of the cup bottom shall be controllled to 0.0610 to 0.0630 by coining.NOTE 4Materal: aluminum alloy QQ-A-318 (5052) temper H32.All dimensions in inches.FIG. 5 One-Piece Specimen CupD2512 174NOTE 1Break sharp edges 0.015.NOTE 2Surfaces marked shall be parallel within 0.002 TI
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