1、Spacem MATERIAL400 Commonwealth Drive, Warrendale, PA 15096-0001SPECIFICATIONIssued 10-l-89Submitted for recognition as an American National StandardSEALING COMPOUND, POLYTHIOETHER ELASTOMERICTwo PartElectrically Conductive1. SCOPE:1.1 Form:This specification covers a room-temperature curing, electr
2、icallyconductive, elastomeric polythioether sealant.1.2 Application: Primarily to provide an electrically conductive sealant ormetal joint interface for shielding purpose.1.3 Safety- Hazardous Materials: While the materials, methods, applications,and processes described or referenced in this specifi
3、cation may involve theuse of hazardous materials, this specification does not address the hazardswhich may be involved in such use. It is the sole responsibility of theuser to ensure familiarity with the safe and proper use of any hazardousmaterials and to take necessary precautionary measures to en
4、sure the healthand safety of all personnel involved.2. APPLICABLE DOCUMENTS: The following publications form a part of thisspecification to the extent specified herein. The latest issue of SAEpublications shall apply. The applicable issue of other documents shall beas specified in AMS 2350.2.1 SAE P
5、ublications: Available from SAE, 400 Commonwealth Drive, Warrendale,PA 15096.2.1.1 Aerospace Material Specifications:AMS 2350 - Standard and Test MethodsAMS 2473 - Chemical Treatment of Aluminum Alloys, General Purpose CoatingAMS 2825 - Material Safety Data SheetsAMS 4037 - Aluminum Alloy Sheet and
6、Plate, 4.4Cu - 1.5Mg - 0.6Mn, (2024; -T3 Flat Sheet, -T351 Plate), Solution Heat TreatedSAE Technical Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences.The use of this report is entirely voluntary, and its applicability and suitabil
7、ity for any particular use, including any patent infringementarising therefrom, is the sole responsibility of the user.”AMS documents are protected under United States and international copyright laws. Reproduction of these documents by anymeans is strictly prohibited without the written consent of
8、the publisher.Society of Automotive Engineers, Inc.Printed in U.SA.EThe Engineering SocietyFor Advancing MobilityLand Sea Air and SpaceAEROSPACEAMS 3266Copyright 1989All rights reserved.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking perm
9、itted without license from IHS-,-AMS 3266 Page 22.2 ASTM Publications: Available from ASTM, 1916 Race Street, Philadelphia, PA19103.ASTM B 117 - Salt Spray (Fog) TestingASTM D 412- Rubber Properties in TensionASTM D 792 - Specific Gravity (Relative Density) and Density of Plastics byDisplacementASTM
10、 D 1002 - Strength Properties of Adhesives in Shear by Tension Loading,(Metal-to-Metal)ASTM D 2137 - Rubber Property - Brittleness Point of Flexible Polymers andCoating Fabrics2.3 National Aerospace Standard:Available from Aerospace IndustriesAssociation of America, Inc., 1725 DeSales Street, N.W.,
11、Washington, DC20036.NAS 705 - Terminal, Stud-Turret, Single End2.4 U.S. Government Publications:Available from Commanding Officer, NavalPublications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120.2.4.1Federal Specifications:L-P-378 - Plastic Sheet and Strip, Thin Gauge, Polyolefin-CCC-C
12、419- Cloth, Duck, Cotton, Unbleached, Plied-Yarns, Army andNumbered2.4.2 Military Specifications:-and Fuel Cell Cavities, High Adhesion-2.4.3 Military Standards:3. TECHNICAL REOUIREMENTS:3.1 Material: Shall consist of two parts, a base compound and a separate curingagent which, when mixed in proper
13、 proportions, will cure at room temperatureto a rubbery solid.3.1.1 Base Compound:Shall be an uncatalyzed polythioether polymer with nickelfiller.3.1.2 CuringAgent: The curing agent shall be a manganese dioxide poundof sufficiently different color from the base compound to easily identifyan incomple
14、tely mixed system.ASTM D 2240 - Rubber Property - Durometer HardnessQQ-A-200/9 Aluminum Alloy Bar, Rod, Shapes, Tube, and Wire, Extruded 6063MIL-S-8802 Sealing Compound, Temperature-Resistant, Integral Fuel TanksMIL-C-38736 Compound, Solvent, For Use in Integral Fuel TanksMIL-STD-794 - Parts and Equ
15、ipments, Procedures for Packaging and Packing ofCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-Page 3 AMS 32663.1.3 Adhesion Promoter: The adhesion promoter shall be an air drying clearliquid and shal
16、l be included as part of the package with the base compound.3.2 Properties: Compound shall conform to the following requirements:3.2.1 Unmixed Compound:3.2.1.1 Storage Life:The base compound and the curing agent, stored in arequirements of 3.2.2 and 3.2.3 when mixed in proper proportions at anytime
17、up to six months from the date of receipt.3.2.1.2 Tack Free Time, maximum 10 hours 4.5.33.2.2 Mixed, Uncured Compound:3.2.2.1 Application Time: One hour after mixing, the extrusion rate shall benot less than 15 grams/minute, determined in accordance with 4.5.2.3.2.3 Mixed - Cured Compound: The produ
18、ct shall conform to the followingrequirements; tests shall be performed on specimens cut from air-freeslabs prepared as in 4.5.1 and tested in accordance with specified testmethods at 25C 1 (77F 2) and 45 - 55% relative humidity.3.2.3.1 Hardness, Durometer “A“After 72 hours curing, minimum 403.2.3.2
19、 Tensile Strength, minimum 50 psi ASTM D 412(345 kPa) Method A, Die C3.2.3.3 Elongation, minimum 40% ASTM D 412,Method A, Die C3.2.3.4 Specific Gravity 1.9 - 2.25 ASTM D 792,Method A3.2.3.5 Electrical Contact 4.5.4Resistance3.2.3.5.1 Initial, maximum 0.05 ohm3.2.3.5.2 After 1000 hours ASTM B 117, 4.
20、5.4Salt Spray, maximum 1.0 ohm3.2.3.6 Low-Temperature ASTM D 2137,Brittleness Pass Method ATemp: -55C 2,(-65F 2)3.2.3.7 Thermal Stability No sign of blistering 4.5.5or cracking. Hardnessshall change not morethan 15 points frompreproduction valueASTM D 2240closed container at not higher than 25C(77F)
21、 shall meet theCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-AMS 3266 Page 43.2.3.8 Corrosion No visible evidence 4.5.6of pitting corrosionat metal/conductivesealant interface3.2.3.9 Tensile Shear,
22、minimum 40 psi (276 kPa) 4.5.73.3 QUALITY: The sealing compound, as received by purchaser, shall be uniformin quality and condition, and free from foreign materials and fromimperfections detrimental to usage of the compound.4. QUALITY ASSURANCE PROVISIONS:4.1 Responsibilitv for Inspection: The vendo
23、r of the compound shall supply allsamples for vendors tests and shall be responsible for performing allrequired tests. Results of such tests shall be reported to the purchaser asrequired by 4.6. Purchaser reserves the right to sample and to perform anyconfirmatory testing deemed necessary to ensure
24、that the compound conformsto the requirements of this specification.4.2 Classification of Tests:4.2.1 Acceptance Tests: Tests for the following requirements are acceptancetests and shall be performed on each lot:Requirement ParagraphTack-Free Time 3.2.1.2Application Time 3.2.2.1Hardness 3.2.3.1Elect
25、rical Contact Resistance, initial 3.2.3.5.14.2. Preproduction Tests: Tests for all technical requirements arepreproduction tests and shall be performed prior to or on the initialshipment of compound to a purchaser, when a change in ingredients and/orprocessing requires reapproval as in 4.4.2, and wh
26、en purchaser deemsconfirmatory testing to be required.4.2.2.1 For direct U.S. Military procurement, substantiating test data and, whenrequested, preproduction test material shall be submitted to thecognizant agency as directed by the procuring activity, contractingofficer, or request for procurement
27、4.3 Sampling and Testing: Shall be as follows:4.3.1 For Acceptance Tests: Sufficient compound shall be taken at random fromeach lot to perform all required tests. The number of determinations foreach requirement shall be as specified in the applicable test procedureor, if not specified therein, not
28、 less than three, with the exception thattack-free time of mixed compound shall require only one determination.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-Page 5AMS 32664.3.1.1 A lot shall be all c
29、ompound from the same batch of raw materialsprocessed in one continuous run and presented for vendors inspection atone time. A lot may be packaged in smaller quantities and deliveredunder the basic lot approval provided lot identification is maintained.4.3.1.2 When a statistical sampling plan and ac
30、ceptance quality level (AQL) havebeen agreed upon by purchaser and vendor, sampling shall be inaccordance with such plan in lieu of sampling as in 4.3.1 and the reportof 4.6 shall state that such plan was used.4.3.2 For Preproduction Tests: As agreed upon by purchaser and vendor.4.4 Approval:4.4.1 S
31、ample compound shall be approved by purchaser before compound forproduction use is supplied, unless such approval be waived by purchaser.Results of tests on production compound shall be essentially equivalent tothose on the approved sample.4.4.2 Vendor shall use ingredients, manufacturing procedures
32、 processes, andmethods of inspection on production compound which are essentially thesame as those used on the approved sample compound. If necessary to makeany change in ingredients,in type of equipment for processing, or inmanufacturing procedures,vendor shall submit for reapproval a statementof
33、the proposed changes in ingredients and/or processing and, whenrequested, sample compound.Production compound made by the revisedprocedure shall not be shipped prior to receipt of reapproval.4.5 Test Methods:4.5.1 Preparation of Cured Test Specimens: Test specimens of the mixed, curedcompound shall
34、be cut from slabs, nominally 6 x 6 inches (152 x 152 mm)and 0.075 inch 0.008 (1.90 mm 0.20) thick, prepared from a mixture of100 parts by weight of base compound and 10 parts by weight of curingagent, and cured for not less than 72 hours at 25C 1 (77F 2) and45 - 55% relative humidity.4.5.2 Applicati
35、on Time:4.5.2.1 Preparation of Test Sample: The base compound and curing agent, both intheir original unopened containers, together with the required mixingequipment shall be held at 25C 1 (77F 2) for 24 hours 1.base compound and curing agent shall be proportioned, mixed inTheaccordance with manufac
36、turers recommendations, taking care to avoidincorporation of air. Immediately after mixing, sealant shall be placedinto cartridges, for extrusion, with an orifice of 0.125 inch 0.005(3.18 mm 0.13).4.5.2.2 Two to three inches (51 to 76 mm) of sealing compound shall be extrudedinitially to clear trapp
37、ed air. One hour after mixing, the sealingcompound shall be extruded onto a suitable receptacle for one minute ata pressure of 90 psi (621kPa)and the weight in grams measured.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted witho
38、ut license from IHS-,-AMS 3266 Page 64.5.3 Tack-Free Time: An AMS 4037 aluminum alloy test panel, nominally0.040 x 2.75 x 6 inches (1.02 x 69.85 x 152 mm), shall be cleaned andcovered with freshly mixed sealing compound to a depth of 0.125 inch 0.010 (3.18 mm 0.25). The sealing compound shall be all
39、owed to cure at25C 1 (77F 2) and 45% 5 relative humidity. After 10 hours ofcuring, two 1 by 6 inch (25 by 152 mm) pieces of clean L-P-378 plastic sheet, 0.004 inch (0.010 sealing compound and held in place at a pressure of l/2-ounce force persquare inch (0.0002 N/mm) for two minutes. The strips shal
40、l be slowlyand evenly withdrawn at right angles to the sealing compound surface. Theplastic shall come away clean and free of sealing compound.4.5.4 Electrical Contact Resistance:4.5.4.14.5.4.24.5.4.3Test Specimen Preparation: At least ten test specimens shall beprepared as shown in Figure 1 . Drill
41、 two holes using a No. 43 drill onone side on each of the chromate conversion coating treated aluminumangles, approximately 1/2 inch (12.7 mm) apart. Press fit silver platedterminals, conforming to NAS 705, into the drill holes. Swage theterminals to make certain the terminals are held tightly into
42、thealuminum angle. Solvent clean the faying surfaces of the angles withMIL-C-38736 solvent. Mix MIL-S-8802, Class B-2, polysulfide sealantaccording to manufacturers instruction. Apply mixed sealant to bothfaying surfaces. Place a CCC-C-419, Type III, cotton duck cloth,1.0 x 1.5 inches (25 x 38 mm),
43、over the coated surface and impregnatewith sealant. Mate the two angles together and clamp; allow to cure for24 hours at ambient temperature. Also, seal the terminal/angle jointswith the same material. Remove the conversion coating from surface “A“,as shown in Figure 1, with a nylon scouring pad and
44、 clean withMIL-C-38736 solvent. Apply electrically conductive sealant to surface“A“. Assembly shall be left undisturbed for 72 hours while sealant iscuring.Resistance Measurements: A Kelvin connection shall be used to measurecontact resistance. A lOO-milliampere current shall be applied acrossthe te
45、st assembly. The voltage drop shall be measured and resistancecan be calculated using the following formula:Electrical Contact Resistance () =Voltage drop0.1Salt Fog Aging: Not less than five test specimens shall be prepared inaccordance with 4.5.4.1 and subjected to a salt fog test for 1000 hoursin
46、 accordance with ASTM B 117. Thereafter, contact resistance shall bemeasured and shall meet the requirement of 3.2.3.5.4.5.5 Thermal Stability:Specimens, prepared and cured as in 4.5.1, shall betested for hardness in accordance with ASTM D 2240. circulating air ovenand heat age for 48 hours 1 at 121
47、C1 (250F2).The specimensshall be removed from the oven, cooled to 25C 1 (77F 2), andhardness remeasured.mm) nominal thickness, shall be applied to theCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-Pag
48、e 7 AMS 32664.5.6 Corrosion : The test specimens used for the salt fog test (4.5.4.3) shallbe disassembledby removing the conductive sealant exposing the surface ofthe substrate. The faying surface, under the conductive sealant, shall beexamined visually for corrosion and at 10X magnification.4.5.7 Tensile Shear:Shall be determined in accordance with ASTM D 1002 withthe following modifications. Individual test peices shall be made of AMS4037 aluminum, or equival
