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 revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2016 SAE International All rights reserved. No part of this p
3、ublication may 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: +1 724-776-497
4、0 (outside USA) 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/AMS2774E AEROSPACE MATERIAL SPECIFICATION AMS2774 REV. E Issued 1995-07 Revised 2
5、016-01 Superseding AMS2774D Heat Treatment Wrought Nickel Alloy and Cobalt Alloy Parts RATIONALE AMS2774E results from a limited scope ballot to correct errors in Table 4. 1. SCOPE 1.1 Purpose This specification specifies the engineering requirements for heat treatment, by part fabricators (users) o
6、r their vendors or subcontractors, of parts made of wrought nickel or cobalt alloys, of raw materials during fabrication, and of fabricated assemblies in which wrought nickel or cobalt alloys are the primary structural components. 1.2 Application 1.2.1 Alloys Detailed heat treating instructions are
7、specified for the age-hardenable (precipitation-hardenable) and non-age-hardenable alloys listed in 8.2. However, this specification also may be used for alloys other than those listed in 8.2 provided that temperatures, soaking times, and cooling requirements are specified by the cognizant engineeri
8、ng organization. 1.2.2 Heat Treatments Heat treatments covered by this specification are as follows: Solution Treating (see 8.4.7) Annealing (see 8.4.8) Stabilization Annealing (see 8.4.10) Interstage Annealing (see 8.4.13) Stabilization (see 8.4.11) Precipitation (see 8.4.12) Equalization (see 8.4.
9、14) Stress Relief (see 8.4.9). SAE INTERNATIONAL AMS2774E Page 2 of 31 1.3 Safety - Hazardous Materials While the materials, methods, applications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards
10、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 materials and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 2. APPLICABLE DOCUMENTS The issue of the
11、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 to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been cancelled and no supers
12、eding document has been specified, the last published issue of that document shall apply. 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001 Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org. AMS2750 Pyrometr
13、y AMS2769 Heat Treatment of Parts in a Vacuum ARP1820 Chord Method of Evaluating Surface Microstructural Characteristics ARP1962 Training and Approval of Heat-Treating Personnel 2.1.1 Titles of AMS publications listed in Tables 3, 4, 7, and 8 are presented in Appendix A. 2.2 ASTM Publications Availa
14、ble from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM E3 Preparation of Metallographic Specimens ASTM E8/E8M Tension Testing of Metallic Materials ASTM E10 Brinell Hardness of Metallic Materials ASTM E18 Rockwell Ha
15、rdness of Metallic Materials ASTM E21 Elevated Temperature Tension Tests for Metallic Materials ASTM E139 Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials ASTM E292 Conducting Time-for-Rupture Notch Tension Tests of Materials ASTM E384 Knoop and Vickers Hardness of Mat
16、erials SAE INTERNATIONAL AMS2774E Page 3 of 31 2.3 U.S. Government Publications Copies of these documents are available online at http:/quicksearch.dla.mil. MIL-A-18455 Argon, Technical MIL-PRF-27201 Propellant, Hydrogen MIL-PRF-27401 Propellant Pressurizing Agent, Nitrogen MIL-PRF-27407 Propellant
17、Pressurizing Agent, Helium BB-H-1168 Helium, Technical 2.4 CGA Publications (Compressed Gas Association) Available from CGA, 14501 George Carter Way, Suite 103, Chantilly, VA 20151 Tel: 703-788-2700, . CGA G-5.3 Commodity Specification for Hydrogen CGA G-9.1 Commodity Specification for Helium CGA G1
18、0.1 Commodity Specification for Nitrogen CGA G-11.1 Commodity Specification for Argon 3. TECHNICAL REQUIREMENTS 3.1 Equipment 3.1.1 Pyrometry Shall conform to AMS2750. 3.1.2 Furnaces 3.1.2.1 Temperature Uniformity Shall be as shown in Table 1 tested in accordance with AMS2750. 3.1.2.2 Vacuum furnace
19、s shall meet the requirements of AMS2769. 3.1.2.3 Heating Media Protective atmospheres shall be used whenever heat treating temperature is above 1550 F (843 C) unless parts will have sufficient surface material removed after heat treatment to eliminate high temperature atmospheric effects, such as o
20、xidation, alloy depletion, and carburization. Certain of the alloys listed in 8.2 require protective atmospheres for heat treatments under 1550 F (843 C) and these requirements are noted with the detailed heat treating instructions for these alloys. Acceptable protective atmospheres include argon, h
21、elium, hydrogen, vacuum, and vacuum with partial pressure of any of these three gases. In addition, for non-age-hardening alloys, neutral salt baths and exothermic gas atmospheres are acceptable protective atmospheres when approved by the cognizant engineering organization (see 8.4.6). Direct fired
22、furnaces shall be controlled so that there is no direct flame impingement on the parts. SAE INTERNATIONAL AMS2774E Page 4 of 31 3.1.2.3.1 Argon, Helium, and Hydrogen Gases Shall meet the composition requirements of MIL-A-18455 (argon), CGA G-11.1, Grade C (argon), MIL-PRF-27407 (helium), CGA G-9.1,
23、Grade L, minimum (helium), BB-H-1168, Grade A (helium), or MIL-PRF-27201 or CGA G-5.3, Grade B (hydrogen), as applicable. The dew point of the gas shall be -60 F (-51 C) or lower as the gas enters the furnace. Atmospheres of any of these gases in the furnace work zone shall have sufficient purity to
24、 avoid contamination or degradation of any part surfaces which will not have surface material removed after heat treatment. 3.1.2.3.2 Vacuum and Partial Pressure Atmospheres Shall be sufficient to avoid contamination or degradation of any part surface which will not have surface material removed aft
25、er heat treatment. Unless otherwise specified by the cognizant engineering organization, as a minimum, vacuum furnaces shall have a cold leak rate of a maximum of 20 microns (20 m) per hour, which shall be determined 15 to 60 minutes after closing the vessel and evacuation to 50 microns (50 m) or lo
26、wer, and shall be operated at pressures not higher than 10 microns (10 m) of mercury unless argon, helium, hydrogen, or a mixture of argon and helium gas conforming to 3.1.2.2.1 is used to provide a partial pressure. 3.1.2.3.2.1 Argon or helium conforming to 3.1.2.3.1 or a mixture of the two, may be
27、 used to achieve partial pressures whenever necessary to avoid surface alloy depletion by sublimation of high vapor pressure elements such as aluminum and chromium. 3.1.2.3.2.2 Cooling may be accelerated by back-filling with argon or helium conforming to 3.1.2.3.1 or nitrogen conforming to either MI
28、L-PRF-27401, Grade C or CGA G-10.1, Grade L, or combinations thereof, meeting the dew point requirements of 3.1.2.3.1. 3.1.2.3.3 Salt Baths Acceptable only for non-age-hardening alloys and, when approved by the cognizant engineering organization, shall be neutral with respect to the alloy being trea
29、ted so as to avoid contamination or degradation of any part surfaces which will not be machined after heat treatment. 3.1.2.3.4 Exothermic Atmospheres Acceptable only for non-age-hardening alloys and, when approved by the cognizant engineering organization, shall be produced by the combustion of fue
30、l gas in air, shall be neutral to slightly reducing with respect to the parts being treated, and shall be sufficiently low in sulfur content to avoid contamination or degradation of any part surfaces which will not have surface material removed after heat treatment. 3.1.3 Auxiliary Equipment Fixture
31、s, jigs, hangers, trays, racks, etc shall not cause contamination of the surface of parts and shall not reduce the heating, cooling, or quenching rates below those required for proper heat treatment. 3.1.4 Cooling Shall be provided to cool parts according to the heat treatment requirements specified
32、 for each alloy. Acceptable cooling media may include air, oil, water, water-polymer solutions, salt, brine (nominally 10% by weight NaCl), argon, helium, hydrogen, nitrogen, and vacuum. The medium selected shall not contaminate or degrade any part surface which will not be machined after heat treat
33、ment. When air cooling (AC) (see 8.4.15) or rapid air cooling (RAC) (see 8.4.16) is specified, cooling media shall be used which will provide protection, if required, to avoid contamination or degradation of finished surfaces; cooling rates shall be achieved that will be equivalent to, or faster tha
34、n, rates that would be achieved by AC or RAC, as specified. SAE INTERNATIONAL AMS2774E Page 5 of 31 3.1.4.1 Quenching Quenching baths shall permit complete immersion of parts and free movement of the quenchant adjacent to all surfaces of parts. Equipment shall agitate or circulate the quenchant and/
35、or the parts. The volume of the quenchant and the capabilities of auxiliary equipment shall be sufficient to maintain the quenchant temperature shown in Table 2. 3.2 Procedures 3.2.1 Cleaning 3.2.1.1 Prior to Heat Treatment Parts shall be thoroughly cleaned to remove all foreign material, including
36、greases, oils, inks, pencil marks, and metal particles produced by machining or forming operations. 3.2.1.2 After Heat Treatment Parts which have been heat treated in molten salt or cooled in oil, molten salt, brine or water-polymer solution shall be thoroughly cleaned to remove all residues of thes
37、e materials. 3.2.2 Racking 3.2.2.1 Except as permitted in 3.2.2.2, parts shall be racked to ensure uniform heating and cooling throughout the load. Parts shall not be nested unless tests with load thermocouples have demonstrated that the arrangement will not affect uniformity of heating and cooling
38、and will not reduce cooling rate below minimum requirements. 3.2.2.2 Rivets, bolts, nuts, and other small parts may be racked or heated and soaked in baskets or in a continuous furnace. Parts shall not be nested. Maximum thickness of layers, and minimum space between layers, shall be 1 inch (25 mm).
39、 3.2.3 Control Instruments Shall be set either at the set temperature (see 8.4.5) specified or at the offset temperature (see 8.4.5) based on the last temperature uniformity determination. The offset temperature shall be within 5 F (3 C) for precipitation treatments, and 10 F (6 C) for other treatme
40、nts, of the specified set temperature and shall be posted on the instrument. The offset temperature shall be selected to optimize the temperature distribution within the furnace so that the highest and lowest temperatures are equidistant from the set temperature. 3.2.3.1 The posting of the offset te
41、mperature shall include, or consist of, a statement of both the “desired” temperature and the corresponding “set” temperature; e.g., “When 1000 F is desired, set at 1004 F.” 3.2.4 Heat Treatment Shall be performed as follows unless an alternate treatment has been specified by the purchase order or b
42、y the cognizant engineering organization. 3.2.4.1 The specified solution, annealing, stress-relief, and stabilization treatment for the non-age-hardening alloys listed in 8.2 shall be performed in accordance with Table 3. The specified solution, stabilization, precipitation, annealing, and stress re
43、lief treatments for age- hardening alloys listed in 8.2 shall be performed in accordance with Table 4. Soaking times from Table 5 shall be used when soaking times are not specified in Table 3. Tolerances for the soaking times for both age-hardening and non-age-hardening alloys shall be as shown in T
44、able 6. 3.2.4.1.1 Parts made of age-hardening alloys shall be heat treated to the precipitation hardened condition. When a stabilization heat treatment is also shown for the alloy in Table 4, stabilization shall be applied to solution treated parts before precipitation treatment. SAE INTERNATIONAL A
45、MS2774E Page 6 of 31 3.2.4.1.2 Where temperature ranges are specified in Tables 3 and 4, it is the responsibility of the heat treatment processor to select, for each lot of material, the specific temperature and time, within the ranges specified, which will produce heat treated parts meeting all tec
46、hnical requirements of the drawing and applicable material specification. 3.2.4.2 Other Alloys Not Listed in 8.2 and Fabricated Assemblies of Cast and Wrought Alloys Heat treatments for alloys not covered herein and for assemblies of cast alloys fabricated with wrought forms of the nickel or cobalt
47、alloys in which the cast material is the primary structural component, shall be as specified by the purchase order or by the cognizant engineering organization. This information shall include the heat treatment name (e.g., annealing, precipitation), the set temperature, the soaking time, and quencha
48、nt or cooling medium. 3.2.4.3 Assemblies of Castings and Wrought Alloys If wrought alloys covered by this specification are fabricated with castings into a single assembly in which the wrought material is the primary structural component, the heat treatment designated for the wrought material shall
49、be used for the assembly. 3.2.5 Start of Soaking Time 3.2.5.1 Batch Furnaces Soaking time starts when all temperature sensors reach the specified set or offset temperature or, if load thermocouples (see 8.4.4) are used, when the part temperature reaches the temperature described by the set or offset temperature minus the appropriate tolerance (3.1.2.1). 3.2.5.1.1 Vacuum Furnaces Unless otherwise specified by
