1、Comments, suggestions, or questions on this document should be addressed to Defense Supply Center Richmond, ATTN: DSCR-VEB, 8000 Jefferson Davis Highway, Richmond, VA 23297-5616, or e-mailed to STDZNMGTdla.mil. Since contact information can change, you may want to verify the currency of this address
2、 information using the ASSIST database at https:/assist.daps.dla.mil/. AMSC N/A FSC 6850 INCH-POUND MIL-DTL-46110C 30 December 2009 SUPERSEDING MIL-C-46110B 17 January 1984 DETAIL SPECIFICATION COATING COMPOUND, OXIDE BLACK Reactivated after 30 December 2009 and may be used for new and existing desi
3、gns and acquisitions. This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers one grade of a coating compound for use in blackening ferrous metals to conform to MIL-DTL-13924, class 1 (for wrought iron, plain
4、carbon, and low alloy steels). 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3 and 4 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as exam
5、ples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of the documents cited in sections 3 and 4 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications
6、. The following specification forms a part of this document to the extent specified herein. Unless otherwise specified, the issues of this document are those cited in the solicitation or contract. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-D
7、TL-46110C 2 DEPARTMENT OF DEFENSE SPECIFICATION MIL-DTL-13924 - Coating, Oxide, Black, for Ferrous Metals (Copies of this document are available online at https:/assist.daps.dla.mil/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.3 N
8、on-government publications. The following document forms a part of this document to the extent specified herein. Unless otherwise specified, the issues of this document are those cited in the solicitation or contract. AMERICAN SOCIETY FOR QUALITY (ASQ) ASQ Z1.4 - Sampling Procedures and Tables for I
9、nspection by Attributes (Copies of this document are available from http:/www.asq.org/ or American Society of Quality, 600 North Plankinton Avenue, Milwaukee, WI 53203.) 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this doc
10、ument and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Material. The coating compound shall consist of ground flake or granular
11、 sodium hydroxide (NaOH) and granular or bead sodium nitrate (NaNO3) intimately blended together as a coarse, dust-free material. The coating compound shall contain no added sulfur compounds, other than those present in the basic chemical ingredients. The particle size shall not be greater than 6.35
12、 millimeter (mm) (0.25 inch) maximum for any dimension when examined visually. The coating compound shall be capable of producing a black oxide coating meeting the requirements of MIL-DTL-13924, class 1. 3.2 Color. The mixture shall have a white or pale yellow color when examined in accordance with
13、4.3.3. 3.3 Chemical requirements. The mixture shall conform to the applicable chemical requirements specified in table I when tested as specified in the corresponding test paragraphs in section 4. 3.4 Workmanship. The material shall be processed in a manner that will produce a uniform mixture when e
14、xamined visually (see 4.3.3). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-46110C 3 TABLE I. Chemical requirements. Property Percentage Test method Moisture 0.5 max 4.3.4 Insoluble matter 0.5 max 4.3.5 Chlorates (as NaClO3) 0.06 max 4.3.6
15、Chlorides (as NaCl) 1.0 max 4.3.7 Sodium hydroxide (as NaOH) 63.0 min 4.3.9 Carbonate (as Na2CO3) 1.3 max 4.3.10 Total alkalinity (as Na2O) 48.8 min 4.3.11 Sodium nitrate (as NaNO3) 33.0 min 4.3.12 Calcium oxide (as CaO) 0.1 max 4.3.13 Magnesium (as MgO) 0.1 max 4.3.14 Sulfates (as Na2SO4) 0.5 max 4
16、.3.15 4. VERIFICATION 4.1 Conformance inspection. Conformance of the material to the requirements of this specification shall consist of an examination for acceptability of quality control methods used by the manufacturer, examining and testing the acceptance samples (see 4.2.3) for all the requirem
17、ents. 4.2 Sampling. 4.2.1 Inspection lot. A lot shall consist of the material produced by one manufacturer under essentially the same manufacturing conditions with no change in materials and provided the operation is continuous. In the event that the process is a batch operation, each batch shall co
18、nstitute a lot (see 6.3). 4.2.2 Nondestructive examination. Sampling shall be conducted in accordance with ASQ Z1.4, inspection level II, with the Acceptance Quality limit (AQL) as specified in the contract (see 6.2). 4.2.3 Sample of tests. Three separate 0.454 kilograms (kg) (1-pound) samples shall
19、 be taken from each inspection lot. When the material is produced by a batch process the three samples shall be taken at different locations within each batch or from three separate containers. When the material is produced by a continuous-run process the three samples shall be taken so as to repres
20、ent, respectively, the first part, the middle part, and the last part of the run of the constituted inspection lot. The individual specimens shall be tested as specified in 4.3. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-46110C 4 4.2.4 E
21、xamination of filled containers. A sample of filled containers shall be taken at random in accordance with ASQ Z1.4, inspection level II, with the AQL as specified in the contract (see 6.2), checked for defects listed in 4.2.5. 4.2.5 Classification of defects. The classification of defects with resp
22、ect to preparation for delivery (see section 5) is as follows. 4.2.5.1 Critical classifications. No items are classified as critical. 4.2.5.2 Major classifications. The following items are classified as major. Major: 101 Unit of shipping container not as specified. 102 Quantity of material per unit
23、or shipping container not as specified. 103 Closure of unit or shipping container not as specified. 104 Unit or shipping container damaged. 105 Evidence of sifting or leakage. 106 Marking of unit or shipping container, illegible, incorrect, or incomplete. 4.3 Inspection methods. Unless otherwise spe
24、cified, the chemical values in table I shall apply to the average of the determinations made on the product. 4.3.1 Mixture conformance. Conformance of the mixture to the requirements for material (see 3.1) and workmanship (see 3.4) shall be determined by processing 50 mm x 100 mm x 3 mm (2“ x 4“ x 1
25、/8“) panels of low carbon steel, cold rolled, in a prepared aqueous solution (approximately 1079 grams per liter (g/l) (9 pounds per gallon) operated at a rolling boil at 140 to 152 C (284 to 305 F) for a period of 30 minutes, maximum. The panels shall be examined and tested for compliance of the bl
26、ack oxide coating with class 1 of MIL-DTL-13924. Note: For safety, the procedure described in 4.3.1 should be performed in a metal container. 4.3.2 Tests. Distilled water and analytical reagent grade chemicals shall be used throughout the tests. Where applicable, blank determinations shall be run an
27、d corrections applied where significant. Tests shall be conducted as follows: 4.3.3 Color and form. The composite and individual specimens shall be visually examined for compliance with 3.2 and 3.4. 4.3.4 Moisture (see 6.4). Transfer a weighed 10 gram (g) portion of the mixture to a previously tared
28、 shallow weighing bottle, heat in a convection oven for 2 hours at 150 3 C (302 5 F), cover, cool in a desiccator and weigh. Calculate the loss in weight as the percentage of moisture in the sample. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL
29、-DTL-46110C 5 Percent moisture = 100 (A - B) W where: A = Weight of bottle plus sample before drying in grams. B = Weight of bottle plus sample after drying in grams. W = Weight of sample in grams. 4.3.5 Insoluble matter. Transfer a weighed 25 g sample of the mixture to a beaker. Heat to boiling wit
30、h 200 milliliters (ml) of distilled water and decant the solution through a filtering crucible of fine porosity having a nominal maximum pore diameter of 4.5 to 5 micrometers (microns) which has been dried at 105 5 C (221 9 F) and weighed. Rinse the beaker with boiling distilled water and transfer a
31、ny adhering insoluble matter to the filter. Decant the wash water from the beaker through the filter. The filtering crucible shall be dried in an oven at 105 5 C (221 9 F) for 3 hours, cooled in a desiccator and weighed. The increase in weight shall be calculated as percent insoluble matter as follo
32、ws: Percent insoluble matter = 100 (A - B) W where: A = Weight of crucible plus residue in grams. B = Weight of crucible in grams. W = Weight of sample in grams. 4.3.6 Chlorates. Transfer a weighed 25 g sample of the dried mixture to a beaker and dissolve in hot distilled water. Add sufficient nitri
33、c acid (HNO3) to make the solution acid to litmus and then add 5 ml of nitric acid and an excess of silver nitrate (AgNO3) solution and stir. Filter the solution to remove any chlorides that may have been precipitated. Add to the solution 10 ml of 30 percent formaldehyde solution and heat on the wat
34、er bath for 30 minutes. Chlorate is thus reduced to chloride and precipitated by the excess silver nitrate. Filter off the precipitate on a tared filtering crucible of fine porosity having nominal maximum pore diameter of 4.5 to 5 microns, which has previously been dried at 105 5 C (221 9 F). Dry th
35、e crucible and precipitate for 3 hours at 105 5 C (221 9 F). Cool in a desiccator and weigh. Calculate the percentage of sodium chlorate (NaClO3) as follows: Percent sodium chlorate = 74.3 A W where: A = Weight of precipitate in grams. W = Weight of sample in grams. Provided by IHSNot for ResaleNo r
36、eproduction or networking permitted without license from IHS-,-,-MIL-DTL-46110C 6 4.3.7 Chlorides. Carefully weigh a 25 g dried sample of the mixture and transfer it to a 600 ml beaker. The sample shall be dissolved in 300 ml of hot (approximately 85 C (185 F) distilled water and 35 ml of concentrat
37、ed nitric acid added. Add 25 ml of approximately 0.1 N silver nitrate solution to the solution with the aid of a pipette. The precipitate shall be heated to boiling on a hot plate with occasional stirring, and boiled moderately for approximately 2 minutes with constant stirring. The beaker and conte
38、nts shall be removed from the hot plate. The precipitate shall be allowed to settle (if the precipitate does not settle rapidly it is permissible to filter the solution as specified and test the filtrate) and one drop of the supernatant liquid shall be added to one drop of a one percent solution of
39、sodium chloride (NaCl) on a black porcelain spot plate. If no precipitate occurs on the spot plate, a second 25 ml portion of silver nitrate solution shall be added to the sample, boiled as indicated above, and the spot test repeated. The addition of silver nitrate solution shall be continued and th
40、e spot test repeated as specified above until a precipitate of silver chloride (AgCl) is obtained. The supernatant solution shall be filtered through a tared Pyrex sintered glass crucible of fine porosity, having a nominal maximum pore diameter of 4.5 to 5 microns, and with the aid of suction, the f
41、iltrate shall be collected in a 1000 ml filtering flask. The silver chloride precipitate shall be transferred quantitatively to the filtering crucible with the aid of five 20 ml portions of 1:100 nitric acid solution and one 20 ml portion of distilled water. The crucible and contents shall be dried
42、in an oven at 105 5 C (221 9 F) for 3 hours. The crucible shall be cooled in a desiccator and weighed. The percent chlorides, as sodium chloride in the sample, shall be calculated as follows: Percent sodium chloride = 40.8 (A - B) W where: A = Weight of crucible plus precipitate in grams. B = Weight
43、 of crucible grams. W = Weight of sample in grams. 4.3.8 Preparation of solutions. 4.3.8.1 Barium chloride solution. Dissolve 10 g of barium chloride dihydrate (BaCl2 2H2O) in freshly boiled and cooled distilled water and dilute to 100 milliliters. Use this solution in 4.3.9 and 4.3.15. 4.3.8.2 Samp
44、le test solution. Weigh quickly to the nearest milligram into a glass-stoppered weighing bottle approximately 30 g of the sample material (see 6.4). Transfer the weighed material to a 1-liter volumetric flask, rinsing the bottle several times with water to assure complete transfer of the material. A
45、dd sufficient freshly boiled and cooled water to half fill the flask and agitate the contents until all solid material is dissolved. Cool to room temperature and dilute with water to mark. Save this test solution for determinations 4.3.9, 4.3.12, 4.3.13, and 4.3.15. Use the above sample weight as S
46、in calculations of 4.3.9 through 4.3.15. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-46110C 7 4.3.9 Sodium hydroxide. Pipette 50.0 ml of test solution (see 4.3.8.2) into a 250 ml Erlenmeyer flask, add 25 ml of a neutral 10 percent aqueous
47、 solution of barium chloride (see 4.3.8.1), and titrate with 0.5 N hydrochloric acid (HCl), using 3 drops of phenolphthalein (C20H14O4) solution, to disappearance of the pink color. Save this solution for the carbonate determination in 4.3.10. Calculate the percent sodium hydroxide as follows: Perce
48、nt sodium hydroxide = 80 V N S where: V = Volume of hydrochloric acid solution used in ml. N = Normality of hydrochloric acid solution used. S = Weight of specimen used in grams (see 4.3.8.2). 4.3.10 Carbonate. Add 2 drops of methyl orange indicator to the solution reserved from the sodium hydroxide
49、 assay (see 4.3.9) and titrate with 0.1 N hydrochloric acid solution to a pink color, which persists for one minute. Calculate the percent of carbonate as sodium carbonate (Na2CO3) as follows: Percent carbonate = 212 B M S where: B = Volume of hydrochloric acid solution used in ml. M = Normality of hydrochloric acid solution used. S = Weight of specimen used in gr
