1、I “NOT MEASUREMENT SENSITIVE I Class 1 Class 2 Class 3 SEE TABLE 1 MIL-C-87115A 15 OCTOBER 1989 SUPERSEDING MIL-(2-87115 21 December 1977 MILITARY SPECIFICATION COATING, IMMERSION zrm PLARE/CMROMATE DISPERSION This specification is approved for use by all Departments and Agencies sf the Department o
2、f Defense. 1. SCOPE 1.1 Scope. This specification covers zinc flake/chrsmate dispersion coatings which shall be topcoated with a clear, no sealer, or black sealer. 1.2 Classification 1.2.1 Classes. Zinc flake/chromate dispersion coatings shall be of the following classes, as specified (see 6.2): 1.2
3、.2 Types. Zinc flake/chromate topcoatings shall be of the following types, as specified (see 6.2): Type I - no sealer Type II - clear sealer Type III - black sealer Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document be ad
4、dressed to: ASD/ENES, Wright-Patterson AFB OH 45433-6503, by using the self-addressed Standardization Document Improvement (DD FORM 1426) appearinq at the end of this document or by letter. AMSC N/A AREA MFFP DISTRIBUTION STATEMENT A: Approved for public release, distribu- tion is unlimited. - - - ”
5、 - _ THIS DOCUMENT CONTAINS 9 PAGES. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-87115A 2. APPLICABLE DOCUMENTS 2.1 Government documents 2.1.1 Specifications and standards. The following specifications and standards form a part of this docu
6、ment to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto in the solicitation (see 2.4.1 and 6.2). SPECIFICATIONS MILITARY MIL-S-5002
7、Surfaces Treatments and Inorganic Coatings Metal Surfaces of Weapons Systems 4 1 (Unless otherwise indicated, copies of the military specifications and standards are available from the Naval Publications and Forms Center, (ATTN: NPODS), 5801 Tabor Avenue, Philadelphia, PA 19120-5099. 2.2 Non-Governm
8、ent publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of th documents which are DoD adopted are those listed in the issue of the DODISS specified in the solicitation. Unless otherwise specified, the issues of doc
9、uments not listed in the DODISS are the issues of the documents cited in the solicitation (see 6,2). O AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM B-117-85 Salt Spray (Fog) Testing, Standard Method ASTM B-487-85 Standard Method for Measurement of Metal (DoD adopted) and Oxide Coating Thic
10、kness by Microscopical Examination of a Cross Section (DoD adopted) Coating Thickness by the Magnetic Method: Nonmagnetic Coatings on Magnetic Basis Metals (DoD adopted) ASTM B-499-85 Standard Test Method for Measurement of (Application for copies should be addressed to the American Society for Test
11、ing and Materials, 1916-*Race Street, Philadelphia, PA 19103-1137). 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-87115A 2.3 Order of precedence. In the event of a conflict between the text of this document and the references cited herein,
12、the text sf this document takes place. Nothing in this document, however, supersedes applicable laws and regulations unless a specific pexemption has been obtained. 3. REQUIREMENTS 3.1 Materials. The materials used shall be of such as to produce zinc flake/chromate coatings which csnfrm to this spec
13、ification. 3.2 Equipment and processes. The equipment and processes employed to produce coatings shall be capable of providing a uniform coating in accordance with the detailed requirements of this specification and shall be approved by the procuring activity. 3.2.1 Process. The process used to depo
14、sit the coating shall be such that a temperature rise in the parts shall not occur that will cause adverse action between the coating and the substrate, or adverse effects to the substrate. 3.3 Cleaninq. Prior to coating, surfaces shall be free of scale, dirt, oils and other contaminants. Cleaning s
15、hall be accomplished using materials and processes which have no damaging effect on the substrate metal, including freedom from pits, integranular attack, embrittlement and significant etching. 3.4 Application. Unless otherwise specified, the coating shall be applied after all machining, bracing, we
16、lding, forming and perforating of the article have been completed. 3.4.1 Area of deposit. The coatings shall completely cover all visible surfaces, including roots of threads, recesses and sharp corners. 3.4.2 Deposit of basis metal. Unless otherwise specified by the procuring activity, coating shal
17、l be deposited directly on the basic metal, without a preliminary coating of other metal. 3.5 Appearance and cure. Type I and type II shall have a uniform metallic gray appearance free from tears and other discontinuities. Type III shall have a bIack finish. All classes shall be thoroughly cured whe
18、n tested per 4.5.1. 3.6 Hiqh temperature. Type I and II shall not be used on parts which, in service, reach a temperature higher than 650F or come in direct contact with parts which reach this temperature. For type III this temperature is 3500F. 3 Provided by IHSNot for ResaleNo reproduction or netw
19、orking permitted without license from IHS-,-,-MIL-C-87115A 3.7 Coating Weiqht. Unless otherwise specified, the coating weight shall be specified in table I. TABLE I. Coatinq thickness and weiqht . Thickness Final Coating Weight Grams/Square Milligrams/Square Class Millimeter Inches Meter Foot 1 0.00
20、25-0.0051 0.00010-0.00020 10.8-20.4 1000-1900 2 0.0051-0.010 0.00020-0.00040 20.4-30.1 1900-2800 2 0.010 -0.028 0.0004 -0.0020 30.1-64.6 2800-6000 3.7.1 Top Coatinq 3.7.1.1 Class 1. Class 1 coating shall have no sealer (type I). 3.7.1.2 Class 2. Class -2 shall be top coated with clear sealer (type 1
21、1) 3.7.1.3 Class 3. Class 3 shall be top coated with black sealer (type III). 3.7.2 Applications. Class 1 shall be used .for moderately corrosive exposure conditions. Classes 2 and 3 shall be used for severely corrosive exposure conditions. 3.7.3 lass 2, and class 3 thickness. Holes, recesses, inter
22、nal threads and other areas where a controlled deposit cannot normally be obtained shall not be subject to a thickness requirement, but there shall be no bare areas. 3.7.4 Enqineerinq drawinq dimensions. Unless otherwise specified, the dimensions given on an engineering drawing are the before-coatin
23、g dimensions. 3.8 Stripping of coatings. Parts to be reached shall be stripped by techanical means or in a suitable caustic solution. 3.9 Corrosion resistance. Coated parts or specimens shall show no evidence of corrosion of the basis metal when exposed for the periods of time shown in table -II in
24、accordance with the method 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-87115A specified in 4.5.4. The appearance of white corrosion products on the coating during the test period shall not be cause for re j ection. TABLE II. Salt spray te
25、st Class 3 Test period (hours) 1 240 2 400 3 400 3.10 Adhesion characteristics. Parts to these specifications shall be tested as per 4.5.3. 3.11 Workmanship 3.11.1 Basis metal. The basis ;metal shall be substantially free from defects that will be detrimental to the appearance or the protective valu
26、e of the coating. It shall be subjected to such deposits as hereinafter specified. 3.11.2 Coating. The immersion zinc flake/chromate dispersion coating shall be smooth, fine grained, adherent, uniform in appearance, free from straining, pits, burning and other defects. The coating shall show no indi
27、cation of contamination of improper operation of equipment used to produce the deposit, such as excessively powdered or darkened coatings All details of workmanship shall conform to the best practice for high quality coating. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unless
28、otherwise specified in the contract, the contractor is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified in the contract, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements
29、 specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to assure supplies and services conform to prescribed requirements. Provided by IHSNot for ResaleNo
30、reproduction or networking permitted without license from IHS-,-,- - - RIL-C-87LL5A RF W q99790b 01.123202 7 - - - - - MIL-C-87115A 4.1.1 ince. All items shall meet all requirements of sections 3 and 5. The inspection set forth in this specification shall become a part of the contractors overall ins
31、pection system or quality program. The absence of any inspection requirements in the specification shall not relieve the contractor of the responsibility of ensuring that all products or supplias submitted to the Government for acceptance comply with all requirements of the contraet Sampling in qual
32、ity conformance does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to acceptance of defective material. 4.2 Classification. W11 the tests required for the testing are classified as quality conformance tests, for which necessary sa
33、mpling techniques and the methods of testing are specified in this section. 4.3 Inspection conditions 4.3.1 Separate specimens. When the coated articles are of such Esrm or material as to be not readily adaptable to a test specimen herein, or for destructive tests, or for the sampling of small lot s
34、izes, the tests shall be made by use sf separate specimens coated concurrently with the articles represented. The separate specimens shall be of a basis metal equivalent to that of the articles represented, except that corrosion resistance (3.9), shall be determined by coating 4930 alloy steel speci
35、mens. Equivalent basis metal. includes a chemical composition and finish of surface prior to coating. For example, a cold-rolled steel surface should not be used to represent a hot-rolled steel surface. Due to the impracticality of forging or casting separate specimens, hot-rolled steel specimens ma
36、y be used to represent forged and cast steel articles. Heat-treat histories should be as nearly identical as possible (see 6.3). 4.3.1.1 Specimen tests. The separate specimens shall be strips approximately l-inch wide, 4 inches long, and 0.04-inch thick, for thickness and adhesion tests (4.5.2 and 4
37、.5.3), but shall be at least 4 inches wide, C inches long, and any convenient thickness for all other tests. These specimens shall be introduced into a lot at regular intervals prior to -the cleaning operation preliminary to coating and shall not be separated therefrom until after completion of the
38、processing. Conditions affecting the coating of the specimens, including the spacing and positioning with respect to vapor sources and to other object being coated, shall correspond as nearly as possible to those affecting the significant surfaces of the articles represented. Separate specimens shal
39、l not beeused for thickness measurements unless the necessity for their use has been demonstrated. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-87115A O 4.4 Quality conformance tests 4.4.1 E. A lot shall consist of coated articles of appro
40、ximately the same size, shape, type, and class of coating. In the case of short production runs, a lot for inspection purposes may be made up of a group of small lots coverings several orders of pazts similar in size and shape and coated under similar conditions. 4.4.2 Samplinq for destructive tests
41、 of coatinq. Random samples for the 4.5 test methods shall be taken as follows: 4.4.2.1 For coating weiqht. A random sample shall be taken of enough coated parts/specimens to have at least 25 square inches or 160 square centimeters of surface area. 4.4.2.2 For thickness and adhesion. A random sample
42、 of two articles shall be taken from an inspection lot or two separately coated specimens shall be prepared in accordance with 4.3 to represent such inspection lot. 4.4.2.3 For corrosion resistance. A random sample of two articles shall be taken from an inspection lot at a minimum of once per month
43、or two separately coated specimens shall be prepared in accordance with 4.3 to represent an inspection lot. Failure of any sample shall require random sampling as mentioned above for each inspection lot for five consecutive inspection lots without failure . 4.5 Test methods. O 4.5.1 Appearance and c
44、ure. All classes shall be thoroughly cured as indicated by the appearance of a yellow color when 1 to 4 drops of concentrated ammonium hydroxide (NH4OH) is placed on the surface of a coated part (at room temperature) and left for 15 to 30 seconds. It shall have a uniform metallic gray appearance fre
45、e from tears and other discontinuities. This test shall be run prior to any application of sealers. 4.5.2 Thickness. Thickness determinations may be made by micrometer measurements, or microscopic test, or magnetic test. The magnetic test is applicable only to ferrous alloy substrates. The microscop
46、ic test shall be made per ASTM B487. The magnetic test shall be made per ASTM B499. For reference tests, the microscopic test shall be used. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NIL-C-87L15A MF 7777706 OL1212OL1 O 4.5,3 Adhesion. Coating
47、 shall show no evidence of blistering or other appearance changes after exposure to salt spray testing per ASTM E3.117, and shall show no more than 3.0 mm peel back from intersection of lines scribed and tape tested immediately after a 10-minute recovery period following exposure, and no other peeli
48、ng in area under tape. 4.5.4 Corrosion resistance. The corrosion resistance tests shall be conducted in accordance with the procedure specified in ASTM B117 to determine conformance with 3.9. 5. PACKAGING 5.1 There are no packaging, packing or mar-king requirements applicable to this specification.
49、6. INFORMATION FOR GUIDANCE ONLY (This section contains information cf a general or explanatory nature which is helpful, but is not mandatory.) 6.1 Intended uses. This pollution-free zinc flake/chromate immersion process is intended to be used to replace processes such as cadmium and zinc plate processes which of themselves or because of subsequent treatment processes involve pollution generating activities. The coatings cover
