1、_ SAE Technical Standards 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 suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2013 SAE International All rights reserved. No part of this publication m
3、ay be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970 (outside U
4、SA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AMS2525D AEROSPACE MATERIAL SPECIFICATION AMS2525 REV. D Issued 1972-05 Reaffirmed 2007-11 Re
5、vised 2013-07 Superseding AMS2525C Graphite Coating, Thin Lubricating Film Impingement Applied RATIONALE This revision results from a Five Year Review and includes changes for consistency with other AMS impingement coating documents. 1. SCOPE 1.1 Form This specification covers a coating consisting o
6、f finely-powdered graphite in a heat-resistant inorganic binder. 1.2 Application This coating has been used typically on metal parts and selected nonmetallic materials requiring a coating under 0.0001 inch (2.5 m) thick (See 8.4) for reducing friction or wear or for minimizing galling, but usage is
7、not limited to such applications. 1.2.1 Aluminum, magnesium, and ferrous alloys, other than corrosion-resistant types, either coated or in contact with other parts having this coating, may be susceptible to corrosion. 1.3 Safety - Hazardous Materials While the materials, methods, applications, and p
8、rocesses described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper use of any hazardous material
9、s and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 2. APPLICABLE DOCUMENTS The issue of the following documents in effect on the date of the purchase order forms a part of this specification to the extent specified herein. The supplier may work
10、to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply. SAE AMS2525D Page 2 of 6 2.1 ASTM Publications Available from A
11、STM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM D 1186 Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to a Ferrous Base ASTM D 2510 Adhesion of Solid Film Lubricants ASTM D 2714 Calibra
12、tion and Operation of the Alpha Model LFW-1 Friction and Wear Testing Machine 3. TECHNICAL REQUIREMENTS 3.1 Coating Material Shall consist of finely-powdered graphite in a heat-resistant inorganic binder. The coating, properly applied, shall form a lubricating film conforming to the requirements of
13、3.3. 3.2 Procedure 3.2.1 Cleaning Before applying the coating, surfaces of the basis material shall be thoroughly cleaned. The cleaned surfaces shall be free from oxides and from foreign materials detrimental to coating adhesion. 3.2.2 Masking (and removal) For parts with surfaces on which coating i
14、s not permitted, masking shall be applied (and removed after coating) by a method that will not change the properties of the base material or the applied coating. External shielding between the impingement nozzle and the part may be used instead of masking the part if its effectiveness can be demons
15、trated by inspection. 3.2.3 Surface Finishing Surfaces of parts to be coated shall be honed with 120 to 400 mesh aluminum oxide powder to prepare the basis material for coating. 3.2.3.1 To provide the proper surface for bearing applications, remove all residual metallic particles, whether mechanical
16、ly or electrostatically held. The cleaning method may be the same or different from the one used in 3.2.1, depending on suitability. 3.2.4 Coating The coating material shall be applied to all specified surfaces by spraying at high velocity (impinging) under controlled conditions. 3.2.5 Curing Curing
17、 shall be performed at a temperature not exceeding 310 F (154 C). 3.2.6 Preservation Unless otherwise specified by purchaser, after curing, a supplementary preservative treatment shall be applied to metallic parts subject to corrosion. The preservative treatment shall be removable by a suitable degr
18、easing method. SAE AMS2525D Page 3 of 6 3.3 Properties The coating shall conform to the following requirements: 3.3.1 Adhesion A pressure-sensitive film-backed tape, with an adhesion of not less than 45 ounces per inch (12.5 N/25.4 mm), shall be applied to a flat surface of a coated specimen, rolled
19、 in place, and then rapidly removed in accordance with ASTM D 2510, Procedure B. The lifting of flakes or particles of the coating from the specimen exposing the basis metal is not acceptable. A uniform deposit of powdery material clinging to the tape is acceptable. 3.3.2 Thickness Shall be not grea
20、ter than 0.0001 inch (2.5 m), determined in accordance with ASTM D 1186 or by a method acceptable to purchaser when ASTM D 1186 is not applicable, for example, on a non-magnetic substrate or one for which the stated method is not practical. 3.3.3 Wear Life Average of specimen time to failure shall b
21、e not less than 5 minutes average, determined in accordance with ASTM D 2714, Procedure A, and the following: 3.3.3.1 Prepare specimens in accordance with 3.2 excluding the application of the preservative coating (3.2.6). 3.3.3.2 Prepare the wear tester in accordance with ASTM D 2714, Procedure A. 3
22、.3.3.3 Load coated specimens (ring and block) on the wear tester, adjust counters to zero and run the tester for 5 seconds 3 to ensure alignment of the ring and block 3.3.3.4 Place a one-pound (454 gram) weight on the bale rod and run the tester for 60 seconds 5. 3.3.3.5 Place a second one-pound (45
23、4 g) weight on the bale rod and run to failure. Total test time shall include the time accumulated in 3.3.3.4 and 3.3.3.5. 3.3.4 Thermal Stability Heat specimen to 2000 F 25 (1093 C 14) and hold at temperature for 5 minutes 0.5, air cool to room temperature and hold for 60 minutes 5, followed by imm
24、ersion in liquid nitrogen for 60 minutes 5. Remove the specimens from the liquid nitrogen and permit the specimen to return to room temperature. Visual examination shall show no evidence of damage to the coating. 3.3.5 Appearance The coating shall be uniform, charcoal gray to black in color with blu
25、e or green tint permissible. The coating shall exhibit no voids in the coating exposing the basis material. 3.4 Quality Coating on parts, as received by purchaser, shall be uniform in color, smooth, adherent to basis material, and free from surface imperfections detrimental to performance of the coa
26、ting. Evidence of porosity, blistering, or other conditions detrimental to performance of the coating is not acceptable. SAE AMS2525D Page 4 of 6 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The processor shall supply all samples for processors tests and shall be responsible for
27、 the performance of all required tests. Actual parts, when required for tests, shall be supplied by purchaser. Purchaser reserves the right to sample and to perform any confirmatory testing deemed necessary to ensure that the coating conforms to the specified requirements. 4.2 Classification of Test
28、s 4.2.1 Acceptance Tests Adhesion (3.3.1) and quality (3.4) are acceptance tests and shall be performed on each lot. 4.2.2 Periodic Tests Thickness (3.3.2), wear life (3.3.3), and thermal stability (3.3.4) are periodic tests and shall be performed at a frequency selected by the coating vendor unless
29、 frequency of testing is specified by purchaser. 4.2.3 Preproduction Tests All technical requirements are preproduction tests and shall be performed prior to or on the initial shipment of a coated part to a purchaser, when a change in material and/or processing requires reapproval as in 4.4.2, and w
30、hen purchaser deems confirmatory testing to be required. 4.3 Sampling and Testing Shall be in accordance with the following; a lot shall be all parts of the same material, size, and shape, coated in a continuous series of operations in not more than eight consecutive hours, cured at the same time un
31、der the same conditions, and presented for vendors inspection at one time. 4.3.1 For Acceptance Tests Shall be as shown in Table 1. Test samples shall be randomly selected from all parts in the lot. TABLE 1 - SAMPLING FOR ACCEPTANCE Number of Parts in Lot Quality Adhesion 1 to 6 All 2 7 to 15 7 2 15
32、 to 40 10 2 41 to 110 15 3 111 to 300 25 3 301 to 500 35 4 501 to 700 50 4 Over 700 75 5 4.3.2 For Periodic Tests Sample size and frequency of testing shall be at the discretion of the processor unless a test frequency is specified by the purchaser. 4.3.3 Sample Configuration Nondestructive testing
33、shall be performed whenever practical and authorized herein. Except as noted, actual parts shall be selected as samples for test. SAE AMS2525D Page 5 of 6 4.3.4 Specimens Specimens for adhesion (3.3.1), thickness (3.3.2), and thermal stability (3.3.4) shall be as follows and shall be coated in accor
34、dance with 3.2, excluding the application of the preservative coating as in 3.2.5. 4.3.4.1 Adhesion Specimens shall be panels, approximately 0.20 1 4 inches (5 25 102 mm), and shall be fabricated from same generic class of material as the parts. 4.3.4.2 Thickness Specimens shall be panels, approxima
35、tely 0.20 1 4 inches (5 25 102 mm), fabricated from cold rolled low carbon sheet. 4.3.4.3 Thermal Stability Specimens shall be panels, approximately 0.20 1 4 inches (5 25 102 mm), fabricated from a corrosion resistant steel. 4.3.4.4 Wear life Not less than two specimens shall meet the average wear l
36、ife requirements of 3.3.3. 4.4 Approval 4.4.1 The process and control procedures, or a preproduction sample part, or both, whichever is specified by purchaser, shall be approved by the cognizant engineering organization before production parts are supplied. 4.4.2 The processor shall make no signific
37、ant change to materials, processes, or controls from those on which the approval was based, unless the change is approved by the cognizant engineering organization. A significant change is one which, in the judgment of the cognizant engineering organization, could affect the properties or performanc
38、e of the parts. 4.4.3 Control factors shall include, but not be limited to the following: Cleaning procedure Surface preparation Coating material trade name and manufacturer Impingement procedure and parameters Control of coating process Curing conditions Type of preservative, if applied Periodic te
39、st plan 4.5 Reports The processor of coated parts shall furnish with each shipment a report showing the results of tests to determine conformance to the acceptance test requirements and stating that the coating conforms to the other technical requirements. This report shall include the purchase orde
40、r number, lot number, AMS2525D, part number of the coated parts, and quantity. 4.6 Resampling and Retesting If any specimen used in the above tests fails to meet the specified requirements, disposition of the coated parts may be based on the results of testing three actual parts or three additional
41、specimens for each original nonconforming specimen or part as applicable. Failure of any retest specimen to meet the specified requirements shall be cause for rejection of the coated parts represented. Results of all tests shall be reported. SAE AMS2525D Page 6 of 6 5. PREPARATION FOR DELIVERY 5.1 C
42、oated parts shall be handled and packaged to ensure that required physical characteristics and properties of the coating are preserved. 5.2 Each container of coated parts shall be legibly marked with not less than the purchase order number, lot number, AMS2525D, vendors identification, part number,
43、and quantity. 5.3 Packages of coated parts shall be prepared for shipment in accordance with commercial practice and in compliance with applicable rules and regulations pertaining to the handling, packaging, and transportation of the coated parts to ensure carrier acceptance and safe delivery. 6. AC
44、KNOWLEDGMENT A vendor shall mention this specification number and its revision letter in all quotations and when acknowledging purchase orders. 7. REJECTIONS Parts on which the coating does not conform to this specification, or to modifications authorized by purchaser, will be subject to rejection.
45、8. NOTES 8.1 A change bar (|) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the
46、document, including technical revision. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. 8.2 Dimensions and properties in inch/pound units and the Fahrenheit temperatures are primary; dimensions and properties in SI units and the Celsiu
47、s temperatures are shown as the approximate equivalents of the primary units and are presented only for information. 8.3 Terms used in AMS are clarified in ARP1917. 8.4 By the nature of the process, the thickness of the coating is self-limiting to approximately 0.0001 inch (2.5 m), but thinner coati
48、ngs can be applied. 8.5 Existing products for this lubricating film have been described as compatible with such fluids as distilled water, MIL-PRF-5606 hydraulic fluid, SAE phosphate ester test fluid #1, silicone fluid, UDMG-compatible grease, IFRNA-compatible grease, solid rocket propellants, nitro
49、gen tetroxide, and liquid oxygen. This document does not guarantee compatibility of these products. The User may wish to verify compatibility of the offered coating. 8.6 Purchase documents should specify not less than the following: AMS2525D Basis material and condition Part number of parts to be coated Quantity of parts to be coated Coating thickness if other than as in 3.3.2. PREPARED BY AMS COM
