ARMY MIL-DTL-13924 D-1999 COATING OXIDE BLACK FOR FERROUS METALS《黑色金属涂层、氧化层和黑色涂层》.pdf

1、 NOT MEASUREMENTSENSITIVEMIL-DTL-13924D18 March 1999SUPERSEDINGMIL-C-13924C9 June l980DETAIL SPECIFICATIONCOATING, OXIDE, BLACK, FOR FERROUS METALSThis specification is approved for use by all Departmentsand Agencies of the Department of Defense.1. SCOPE1.1 Scope . This specification covers black ox

2、ide coatings applied to ferrousmetals (wrought iron, carbon, low alloy, and corrosion resistant steels). Blackoxide coatings, with or without a supplementary preservative treatment (see 3.11),may be used where a black surface is required. Only very limited corrosionprotection, under mildly corrosive

3、 conditions, is obtained as a result of blackoxide coating (see 6.1). Black coatings are included in this specification withlimitations as noted in 1.2.1.2 Classification . Black oxide coatings covered by this specification should beof the following classes as specified (see 6.2 and 6.3.2).Class 1 A

4、lkaline oxidizing process (for wrought iron, cast and malleableirons, plain carbon, and low alloy steels).Class 2 Alkaline chromate oxidizing process (for use on certain corrosionresistant steel alloys which are tempered at less than 900 F (482 C).Class 3 Fused salt oxidizing process (for corrosion

5、resistant steel alloyswhich are tempered at 900 F (482 C) or higher).Class 4 Alkaline oxidizing process (for other corrosion resistant steelalloys).Beneficial comments (recommendations, additions, deletions) and any pertinent datawhich may be of use in improving this document should be addressed to:

6、 Director,U.S. Army Research Laboratory, Weapons and Materials Research Directorate,ATTN: AMSRL-WM-M, Aberdeen Proving Ground, MD 21005-5069 by using theStandardization Document Improvement Proposal (DD Form 1426) appearing at the endof this document or by letter.AMSC N/A AREA MFFPProvided by IHSNot

7、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-13924D22. APPLICABLE DOCUMENTS2.1 General . The documents listed in this section are specified in sections 3and 4 of this specification. This section does not include documents in othersections of this specificat

8、ion or recommended for additional information or asexamples. While every effort has been made to ensure the completeness of this list,document users are cautioned that they must meet all specified requirementsdocuments cited in sections 3 and 4 of this specification, whether or not they arelisted.2.

9、2 Government documents .2.2.1 Specifications, standards, and handbooks . The following specifications,standards, and handbooks form a part of this document to the extent specifiedherein. Unless otherwise specified, the issues of these documents are those listedin the issue of the Department of Defen

10、se Index of Specifications andStandards(DoDISS) and supplement thereto, cited in the solicitation (see 6.2).SPECIFICATIONSDEPARTMENT OF DEFENSEMIL-C-53072 Chemical Agent Resistant Coating (CARC) System ApplicationProcedures And Quality Control Inspection(Unless otherwise indicated, copies of the abo

11、ve specifications, standards, andhandbooks are available from the Defense Automated Printing Service (DAPS), Building 4D,700 Robbins Avenue, Philadelphia, PA 19111-5094).2.3 Non-Government publications . The following documents form a part of thisdocument to the extent specified herein. Unless other

12、wise specified, the issues ofthe documents which are DoD adopted are those listed in the issue of the DoDISS citedin the solicitation. Unless otherwise specified, the issues of documents not listedin the DoDISS are the issues of the documents cited in the solicitation (see 6.2).AMERICAN SOCIETY FOR

13、TESTING AND MATERIALS (ASTM)ASTM B117 Operating Salt Spray (Fog) Apparatus (DoD adopted)ASTM F519 Mechanical Hydrogen Embrittlement Testing of Plating Processesand Aircraft Maintenance Chemicals(Application for copies should be addressed to the American Society for Testing andMaterials, 100 Barr Har

14、bor Drive, West Conshohocken, PA 19428-2959.)SOCIETY OF AUTOMOTIVE ENGINEERS, INC. (SAE)AMS 2759/9 Hydrogen Embrittlement Relief (Baking) Of Steel Parts(Application for copies should be addressed to the Society Of AutomotiveEngineers, Inc., 400 Commonwealth Drive, Warrendale, PA 15096.)2.4 Order of

15、precedence . In the event of a conflict between the text of thisdocument and the references cited herein, the text of this document takesprecedence. Nothing in this document, however, supersedes applicable laws andregulations unless a specific exemption has been obtained.Provided by IHSNot for Resal

16、eNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-13924D33. REQUIREMENTS3.1 Materials . The materials for the blackening processes shall be selected bythe contractor. The selected materials shall result in black coatings meeting allthe applicable requirements of this spec

17、ification.3.2 Preparation of basis metal . Prior to the application of the black coatings,the basis metal shall be thoroughly cleaned. The cleaned surfaces shall be free ofrust, scale, grease, oil, paint, or other foreign matter, and shall pass the waterbreak test described in MIL-C-53072. Cleaning

18、materials and methods shall be at theoption of the contractor. The cleaning process shall be performed withoutmeasurable abrasion or erosion.3.2.1 Stress relief . Unless otherwise specified for a particular end itemspecification or drawing, after forming and hardening, and prior to cleaning andcoati

19、ng, objectionable residual stress in ferrous alloy parts having a hardnessgreater than 40 HRC shall be relieved by suitable heat treatment. The temperatureshall be such that maximum relief is given without hardness being reduced to lessthan the specified minimum. Stress relief is not necessary where

20、 it has beendemonstrated that coating has no harmful effect on the coated part.3.2.2 Coating as a final process . Unless otherwise specified, the black coatingsshall be applied after all machining, forming, welding, cold straightening and heattreatment have been completed.3.3 Application of black co

21、atings . The coating shall conform to the classspecified. The specified black coating shall be applied under controlled time andtemperature conditions. All equipment together with solutions or baths shall beproperly maintained and kept free of dirt or possible contaminants. The selectedprocess shall

22、 not reduce the hardness of the parts being processed or expose theparts to temperatures in the temper brittle range of the material, nor shall itcause embrittlement of the steel.3.3.1 Surface attack . The process shall not result in any attack of the surface,either pitting or intergranular.3.4 Alka

23、line oxidizing solutions (classes 1 and 2) . Classes 1 and 2 oxide coatingsshall be formed from a boiling alkaline oxidizing or alkaline chromate oxidizingsolution, respectively.3.4.1 Rinsing . All classes of black oxide coated pieces shall be rinsed in coldwater.3.4.2 Chromic acid dip . After the c

24、old water rinse (see 3.4.1) the pieces shallbe dipped for a minimum of 30 seconds in a 0.06 percent solution (8 oz. chromic acidper 100 gallons water) of chromic acid maintained at a temperature of l50 to l90 F(66 to 88 C) and a pH of 2 to 3. After the chromic acid dip, parts shall be driedwithout f

25、urther rinsing by using warm dry air.3.5 Fused salt oxidizing (class 3) . The temperature of the molten oxidizing saltof class 3 shall not be higher than 900 F (482 C). After suitable immersion, thetreated parts shall be withdrawn, cooled from eight to ten minutes and rinsed in hotwater, l90 F (88 C

26、), followed by thorough cold water rinsing to effect completeremoval of blackening solution. After rinsing, the parts shall be dried by warm dryair and given a chromic acid dip as outlined in 3.4.2.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-

27、DTL-13924D43.6 Alkaline oxidizing (class 4) . The black coating of class 4 shall beprocessed in accordance with instructions furnished by the suppliers of the rawmaterials and the resulting coating shall conform to the applicable requirements ofthis specification.3.7 Coverage and color . Class 1, 2,

28、 3, and 4 coatings (see 1.2) shall cover thebasis metal completely and shall pass the smut test. The color shall be a uniformblack. A slight amount of smut, which is inherent in the process, shall not because for rejection. There shall be no indication of any reddish-brown or greensmut when tested a

29、s in 4.4.1. Smut “spottiness“ shall be classified asunsatisfactory requiring reprocessing.3.8 O xalic acid spot test (class 1, 2, and 3) . The black oxide coatings ofclasses 1, 2, and 3, prior to the application of a preservative, shall pass theoxalic acid spot test for a good quality coating (figur

30、e 3) as specified in 4.4.2.3.9 Resistance to salt spray (fog) (class 4 AISI type 300 series corrosionresistant steel only) . The black coating, of class 4 (300 series only), prior tothe application of a preservative, shall show no signs of corrosion after 96 hoursof exposure in the salt spray test (

31、see 4.4.3).3.10 Hydrogen embrittlement relief treatment . Steel parts that are surface orthrough hardened at 40 HRC and above shall be given a hydrogen embrittlement relieftreatment after application of the oxide coating. Coated springs or other partssubject to flexure shall not be flexed prior to t

32、he embrittlement relief treatment.If an embrittlement relief treatment is required, it shall follow the chromic acidrinse. The embrittlement relief treatment precedes the supplementary preservativetreatment.3.11 Supplementary preservative . Materials for supplementary preservativetreatments and meth

33、ods of application shall be in accordance with the applicablerequirements of the end item specification, or as otherwise specified. Unlessotherwise specified, the supplementary preservative treatment shall be applied tothe clean and dry parts immediately after the final stage of processing.3.12 Work

34、manship . The surface of the coated part shall be uniform in appearanceand free of visible coating defects, such as blisters, pits, roughness, nodules,burning, cracks, or uncoated areas, and other defects that will affect the functionof the coating. The coated parts shall be clean and free of damage

35、.4. VERIFICATION4.1 Responsibility for inspection . Unless otherwise specified in the contract orpurchase order, the contractor is responsible for the performance of all inspectionrequirements (examinations and tests) as specified herein. Except as otherwisespecified in the contract or purchase orde

36、r, the contractor may use his own or anyother facilities suitable for the performance of the inspection requirementsspecified herein, unless disapproved by the Government. The Government reserves theright to perform any of the inspections set forth in this specification where suchinspections are dee

37、med necessary to ensure supplies and services conform toprescribed requirements.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-13924D54.1.1 Classification . All the tests required for the testing are classified asquality conformance tests, f

38、or which necessary sampling techniques and the methodsof testing are specified in this section.4.2 Sampling .4.2.1 Lot . A lot shall consist of coated parts of the same class, same basismetal, and approximately the same size and shape and coated under similarconditions. A maximum of 8 hours continuo

39、us production shall constitute a lot.4.2.2 Selection . The number of random samples selected for nondestructive tests(visual inspection, coverage, color, smut, and workmanship), and destructive tests(oxalic acid spot test, salt spray test, and embrittlement relief test) from eachlot of coated parts

40、shall be defined by the procuring activity (see 6.2).4.3 Acceptance and rejection . The selected coated parts shall meet therequirements in this specification for the represented lot to be acceptable.Failure of any test samples to meet the requirements in this specification shallconstitute rejection

41、 of the entire lot which they represent. Unless otherwisespecified (see 6.2), the tests shall be conducted and the test results acceptedprior to shipment of the lot of coated parts represented by the test samples.4.3.1 Surface attack . Parts shall be examined for pitted surfaces orintergranular atta

42、ck by viewing them at magnifications up to 10x.4.4 Test procedures .4.4.1 Smut test . The test shall be made prior to application of corrosionpreventive compound or after vapor degreasing. Each black oxide coated piece shall beinspected visually under strong light to assure a satisfactory appearance

43、. Eachsample shall also be wiped with a clean white cloth for indications of smut (see 3.7).A slight amount of smut which is inherent in the process is acceptable for all classesof coatings and shall not be cause for rejection.4.4.2 Oxalic acid spot test (class 1, 2, and 3) . The black oxide coated

44、pieces ofclasses 1, 2, and 3 only, prior to the application of a preservative, shall be handledwith clean cotton gloves or the equivalent. Each sample shall have deposited, on oneflat spot of the black oxide coated surface, three drops (0.00676 oz. (0.2 ml) of afive percent solution of oxalic acid.

45、The reaction shall be observed after 30 secondsand up to eight minutes. After eight minutes the panel shall be rinsed and comparedto figures 1, 2, and 3. A light gray center with a lighter border color (figure 1)indicates a poor quality coating. A gray-black center with a light border (figure 2)indi

46、cates a borderline quality coating. The coating shall conform to the good qualitycoating of figure 3 to be acceptable. A black or dark brown center with a lightborder (figure 3) indicates a good quality coating. A good quality coating may show alight border, indicating exposure of metal around the d

47、rops. Parts shall therefore bejudged only on the color and exposure of the metal under the drops.4.4.3 Resistance to salt spray (class 4) . The coated pieces of class 4(AISI type 300 series corrosion resistant steel) shall be subjected to a 5 percentsalt spray (fog) test in accordance with ASTM B117

48、. Exposure time for the blackcoatings, prior to the application of a preservative, or after vapor degreasing,shall comply with the requirements of 3.9.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-13924D64.4.4 Hydrogen embrittlement relief

49、treatment . When specified (see 6.2), ferrousparts shall be baked in accordance with AMS 2759/9, table 1.4.4.4.1 Hydrogen embrittlement relief test . Samples selected in accordance with4.2.2 to determine the adequacy of the hydrogen embrittlement relief treatment,shall be tested in accordance with ASTM F519. When specified (see 6.2), thestandard notched round bar specimen under load control described in annex A1, whichis a part of ASTM F51