1、X0 DELIVERAELE DATA REQUIEiEC BY THIS DGCUMNT KC.L-I-8474C 31 August 1983 SUPERSEDING MIL-I-8474B(MR) 26 May 1965 MILITARY SPECIFICATION INSPECTION OF ALUMIKUM ALLCY FARTS, ILNODIZING PFGCESS FCR This specification is approved for use by all fepartnents and Agencies of the Department of Defense 1. S
2、COPE. 1.1 Scope. This specification covers the use of a chromic acid anodizinc; process for surface inspection for cracks, laps and other defects in parts of alutainum alloy compositions for which the process is compatible. 2. WPLICABLE DOCUMENTS 2.1 Gover ment docurtlent s. 2.1.1 Specifications, st
3、andards, and handbooks. Unless otherwise specifiec3, the following specifications, standards, and handbooks of the issue listed in that issue of the Department of Defense Index of Specifications and Standars (DoDISS). specified in the solicitation form a part of this specification to the extent spec
4、ified herein. r Beneficial comments (recommendations, additions, deletions) and any pertinent data uhich may be of use in improving this document should be addressed to: Ijirector, US Army Materials and Mechanics Research Center, ATTN: DRXKR-SMS, Watertown, MA 02172 by using the self-addressed Stand
5、ardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. / AREA MFFP / “ “ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-I-8C74C S PECIFI CAT IONS MIL-A-8625 - Anodic Coatings, for Aluminum and
6、 Aluminum Alloys (Copies of specifications, standards, handbooks, drawings, and publications required by manufacturers in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the contracting officer. 1 2.2 Order of precedence. In the event
7、 of a conflict between the text of this specification and the references cited herein, the text of this specification shall take precedence. 3. REQUIREMENTS 3.1 Material. The materials shall De as specified herein. When materials are used that are not specifically des.ignated, they shall be entirely
8、 suitable for the purpose. 3.2 Anodic film. The anodic film shall confornl to all the requirements for type I coatings of MIL-A-8625 when tested as specified in 4.3, except for the eollowing : 3.2.1 Rinse. After anodizing, parts shall be rinsed in water for the minimum period necessary to remove sur
9、face chromic acid. The tenperature of the rinse shall not .be higher than the temperature of the anodizing solution. . 3.2.2 Drying. Following the rinse, the parts shall be maintained at room temperature for a minimum o 2 hours, or they shall be maintained for a minimum period of 1./2 hour at 2500 i
10、- 250F. In either case the parts shall be racked or stared in such a manner that the ai.r has free access to the surfaces to be inspected. Air circula.tion, not to exceed 50 linear feet per xinute, may be used to aid in drying. 3.3 Air agitation. Air agitation of the bath shall not De used when part
11、s are in the bath. 3.4 Inspection. Inspection of the ancdized parts shall be by visual . examination of the surface for indications of cracks, forging laps or other defects. 3.5 Indications. Voids in the metal which comrzunicate with the outer surface appear as directional stains of chromic acid. De
12、fects which do not contain voids appear as a directional etch on the surface. Insufficient rinsing in cold water produces stains which may be confused with defects. Stains from insufficient rinsing follow drain patterns, whereas stains from. flaws follow the lines of the defects. 2 Provided by IHSNo
13、t for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-I-8474C 3.6 Rejection. In case of doubt concerning indications of defects, the anodic fih. shall be stripped from the part and the part shall be reanodized. If the same indications are obtained for the second time,
14、the defects shall be considered to Ee present. If the same indications do not reappear, the defects shall be considered to be absent. 3.7 Sealing_. When used as part of the anodic filnt process, sealing shall be aCCGIripliShe after inspection. 3.e Painting. The anodic film shall be acceptable as a p
15、aint base without further processing, provided the film has not become soiled in handling. In case of contamination, the part shall be cleaned with a suitable solvent or with a detergent completely soluble in cold hard water. The cleaning shall not asversely affect. the amdic film. 3.9 Parking. Part
16、s which have satisfactorily met the anodizing inspection reyirements shall be marked with the symbol “A“ in such a manner and location as to be hamless to the part and to preclude the removal, smearing or obliterating of the marking by subsequent handling. The stamps may contain an identificaticn sy
17、rkol of the facility. larking shall be accomplished in one of the follouing ways. 3.9.1 Etching. Unless otherwise specified, parts shall be rrarkec? by etching, employing etching agents and applicaticn methods satisfactory to the procuring activity. 3.9.2 Impression stamping. Impression stamping may
18、 be used where permitted by the applicable specification or drawing. Impressions shall be located in areas adjacent to the part number or the inspectors stamp. 4. GUALITY ASSURANCE PROVISIGNS 4.1 Responsibility for inspection. Unless otherwise specified in the contract or purchase order, the contrac
19、tor is responsible for the performance of all inspecticjn requirements as specified herein. Except as otherwise specified in the contract or purchase order, the contractor may use his own or aty other facilities suitable for the performance of the inspection reciuirements specified herein, unless di
20、sapproved by the Government. The Goverrment reserves the right tc 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. 4.2 hjection. Acceptance or approval of material in the cour
21、se of panufacture shall in no case be construed as a guarantee of the acceptance of the finished product. 4.3 Tests to determine compliance with 3.2 shall be accomplished as required by NIL-A-8625. 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MI
22、L-I-8474C 5. PACKAGING 5.1 Packaging requirements (Not applicable to this specification 1 6. NUTES 6.1 Intended use. The process covered by this specification is intended to be used wehre anodizing procedure is indicated as inspection method for defects in alw,inw. alloy parts. 6.2 The anodic film m
23、ay be stripped by inuncrsing the part for 5 minutes in a solution of 1 gallon of sulphuric acid (specific gravity 1.84), 3-1/2 pounds of chromic acid, and sufficient water to make 10 gallons of solution. For stripping, the temperature OP the solution should be between 1700 and 1800F (76.6 and 82.2OC
24、). 6.3 Specification MIL-I-8474A(USAF) dated 4 February 1957 was cancelled 12 January 1965. That specification was being used by the Department of the Army; therefore .this document represents a reinstatement of the previously cancelled specification and a conversion of it to an Anny document. Cu st
25、 odi ans : Amy Ml? Navy - SH Air Force - 11 Review Activity: Anny - SM Preparing activity : Amy - WR Project No. MFFP-0151 AU.!. GOVERNMENT PRINTING OFFICE 1983 - 606.034/4610 (KBWP# ID-O520A/DISK OllOA. FOR AMElRC USE ONLY) 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
