1、Designation: A957/A957M 15aA957/A957M 18Standard Specification forInvestment Castings, Steel and Alloy, CommonRequirements, for General Industrial Use1This standard is issued under the fixed designation A957/A957M; the number immediately following the designation indicates the yearof original adopti
2、on or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers a group of requirements that are mandatory for
3、castings produced by the investment castingprocess to meet the metallurgical requirements of the following steel casting specifications issued by ASTM.ASTM Designation Title of SpecificationA27/A27M Steel Castings, Carbon, for General Ap-plicationA128/A128M Steel Castings, Austenitic ManganeseA148/A
4、148M Steel Castings, High-Strength, for Struc-tural PurposesA297/A297M Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat-Resistant, forGeneral ApplicationA447/A447M Steel Castings, Chromium-Nickel-Iron Al-loy (25-12 Class), for High-TemperatureServiceA494/A494M Castings, Nickel and Nickel
5、 AlloyA560/A560M Castings, Chromium-Nickel AlloyA732/A732M Castings, Investment, Carbon and LowAlloy Steel for General Application, andCobalt Alloy for High Strength at ElevatedTemperaturesA732/A732M Castings, Investment, Carbon and Low-Alloy Steel for General Application, andCobalt Alloy for High S
6、trength at ElevatedTemperaturesA743/A743M Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion-Resistant, for GeneralApplicationA744/A744M Castings, Iron-Chromium-Nickel, Corro-sion Resistant, for Severe ServiceA747/A747M Steel Castings, Stainless, PrecipitationHardeningA890/A890M Castings, Iron
7、-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex(Austenitic/Ferritic) for General Applica-tionA915/A915M Steel Castings, Carbon and Alloy, Chemi-cal Requirements Similar to StandardWrought GradesA958 Steel Castings, Carbon and Alloy, withTensile Requirements, Chemical Require-ments Similar to
8、 Standard WroughtGradesA958/A958M Steel Castings, Carbon and Alloy, withTensile Requirements, Chemical Require-ments Similar to Standard WroughtGradesA1002 Castings, Nickel-Aluminum Ordered Alloy1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and Related
9、Alloys and is the direct responsibility of Subcommittee A01.18on Castings.Current edition approved Nov. 1, 2015May 15, 2018. Published November 2015May 2018. Originally approved in 1996. Last previous edition approved in 2015 asA957/A957M 15.A957/A957M 15a. DOI: 10.1520/A0957_A0957M-15A. 10.1520/A09
10、57_A0957M-18.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users cons
11、ult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
12、 PA 19428-2959. United States11.2 This specification also covers a group of supplementary requirements that may be applied to the above specifications asindicated therein. These are provided for use when additional testing or inspection is desired and apply only when specifiedindividually by the pur
13、chaser in the order.1.3 When investment castings are ordered, the requirements stated in this specification form an integral part of the materialspecification. In cases of conflict, the requirements of this specification shall take precedence over the individual materialspecification requirements.1.
14、4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformancenonco
15、nformance with the standard.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organizat
16、ion Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A27/A27M Specification for Steel Castings, Carbon, for General ApplicationA128/A128M Specification for Steel Castings, Austenitic ManganeseA148/A148M Specification for Steel Castings, High Strength, for Struct
17、ural PurposesA297/A297M Specification for Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for GeneralApplicationA370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA380A380/A380M Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts,
18、 Equipment, and SystemsA447/A447M Specification for Steel Castings, Chromium-Nickel-Iron Alloy (25-12 Class), for High-Temperature ServiceA488/A488M Practice for Steel Castings, Welding, Qualifications of Procedures and PersonnelA494/A494M Specification for Castings, Nickel and Nickel AlloyA560/A560
19、M Specification for Castings, Chromium-Nickel AlloyA609/A609M Practice for Castings, Carbon, Low-Alloy, and Martensitic Stainless Steel, Ultrasonic Examination ThereofA732/A732M Specification for Castings, Investment, Carbon and Low Alloy Steel for General Application, and Cobalt Alloyfor High Stren
20、gth at Elevated TemperaturesA743/A743M Specification for Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for GeneralApplicationA744/A744M Specification for Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe ServiceA747/A747M Specification for Steel Castings, Stainles
21、s, Precipitation HardeningA751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel ProductsA800/A800M Practice for Steel Casting, Austenitic Alloy, Estimating Ferrite Content ThereofA890/A890M Specification for Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex
22、 (Austenitic/Ferritic) for General ApplicationA903/A903M Specification for Steel Castings, Surface Acceptance Standards, Magnetic Particle and Liquid PenetrantInspectionA915/A915M Specification for Steel Castings, Carbon, andAlloy, Chemical Requirements Similar to Standard Wrought GradesA941 Termino
23、logy Relating to Steel, Stainless Steel, Related Alloys, and FerroalloysA958A958/A958M Specification for Steel Castings, Carbon and Alloy, with Tensile Requirements, Chemical RequirementsSimilar to Standard Wrought GradesA967A967/A967M Specification for Chemical Passivation Treatments for Stainless
24、Steel PartsA991/A991M Test Method for Conducting Temperature Uniformity Surveys of Furnaces Used to Heat Treat Steel ProductsA997 Practice for Investment Castings, Surface Acceptance Standards, Visual ExaminationA1002 Specification for Castings, Nickel-Aluminum Ordered AlloyA1058 Test Methods for Me
25、chanical Testing of Steel ProductsMetricA1067A1067/A1067M Specification for Test Coupons for Steel CastingsA1080 Practice for Hot Isostatic Pressing of Steel, Stainless Steel, and Related Alloy CastingsE29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specification
26、sE94E94/E94M Guide for Radiographic Examination Using Industrial Radiographic FilmE125 Reference Photographs for Magnetic Particle Indications on Ferrous CastingsE165E165/E165M Practice for Liquid Penetrant Examination for General IndustryE186 Reference Radiographs for Heavy-Walled (2 to 412 in. (50
27、.8 to 114 mm) Steel Castings2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.A957/A957M 182E192 Reference Radi
28、ographs of Investment Steel Castings for Aerospace ApplicationsE280 Reference Radiographs for Heavy-Walled (412 to 12 in. (114 to 305 mm) Steel CastingsE340 Practice for Macroetching Metals and AlloysE353 Test Methods for Chemical Analysis of Stainless, Heat-Resisting, Maraging, and Other Similar Ch
29、romium-Nickel-IronAlloysE354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron, Nickel, andCobalt AlloysE446 Reference Radiographs for Steel Castings Up to 2 in. (50.8 mm) in ThicknessE709 Guide for Magnetic Particle TestingE2660 Digital Reference I
30、mages for Investment Steel Castings for Aerospace Applications2.2 SAE Aerospace Recommended Practice:3ARP 1341 Determining Decarburization and Carburization in Finished Parts of Carbon and Low-Alloy Steel3. Terminology3.1 Definitions:3.1.1 The definitions in Test Methods and Definitions A370, Test M
31、ethods, Practices, and Terminology A751, TerminologyA941, and Test Methods A1058 are applicable to this specification and to those listed in 1.1.3.2 Definitions of Terms Specific to This Standard:3.2.1 investment casting, na metal casting that is produced in a mold obtained by investing (surrounding
32、) an expendablepattern with a ceramic slurry that is allowed to solidify. The expendable pattern may consist of wax, plastic, or other material andis removed prior to filling the mold with liquid metal.3.2.2 master heat, na quantity of metal processed in a single furnace or refining vessel at one ti
33、me in such a manner as toproduce the desired composition and properties.3.2.3 sub-heat, na portion of a master heat remelted without additional processing for pouring into castings. Synonyms:Synonymsmelt,production heat.4. Materials and Manufacture4.1 When the purchaser imposes the requirements of t
34、his specification, the manufacturer is responsible for compliance with thespecification requirements during the production and processing of the casting by themselves and any of their subcontractors.4.2 Melting ProcessMaster heats shall be made by the electric furnace process, with or without separa
35、te refining such asargon-oxygen-decarburization (AOD), vacuum-oxygen-degassing (VOD), vacuum-induction-melting (VIM), and so forth, unlessotherwise specified in the individual specification or agreed upon between the customer and producer. Master heats may be useddirectly for producing castings or c
36、onverted into ingot, bar, shot, or other suitable form, not including gates and risers from castingproduction, for later remelting as a sub-heat.4.3 Re-meltingRe-Melting ProcessSub-heats shall be produced from master heat metal in suitable batch sizes by electricinduction furnace, with or without at
37、mosphere protection such as vacuum or inert gas, unless otherwise specified in the individualspecification or agreed upon between the customer and producer. Revert (gates, sprues, risers, and rejected castings) shall not bere-melted except in master heats.4.4 Sampling:4.4.1 If castings are poured di
38、rectly from one or more master heats, then the samples for chemical and other required testingshall also be poured directly from each of the master heats.4.4.2 If castings are poured from a sub-heat, then the samples for chemical and other required testing shall also be poured froma sub-heat of that
39、 same master heat, but not necessarily from the same sub-heat as the castings. The sub-heat used for the testsamples shall be produced using the same melting practices and additions as used to produce the castings.4.4.3 Unless otherwise specified by the purchaser, test specimens may be taken from ca
40、stings or from coupons cast integrallywith the castings, in the same molds as the castings, or in separate molds.4.5 Heat Treatment:4.5.1 Castings shall be heat treated in the working zone of a furnace that has been surveyed in accordance with Test MethodA991/A991M.4.5.2 When castings are heat treat
41、ed at temperatures above 2000F 1100C,2000 F 1100 C, then the working zone shallhave been established by a survey performed at not more than 25F 15C25 F 15 C below nor more than 200F110C200 F 110 C above the minimum heat treatment temperature specified for the grade. If a minimum heat treatmenttemper
42、ature is not specified for the grade, then the survey temperature shall be not more than 50F 30C50 F 30 C below normore than 175F 100C175 F 100 C above the furnace set point used.3 Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.or
43、g.A957/A957M 1834.5.3 The maximum variation in measured temperature as determined by the difference between the highest temperature and thelowest temperature shall be as agreed between the purchaser and producer, except that during production heat treatment, no portionof the furnace shall be below t
44、he minimum specified temperature nor above the maximum specified temperature for the grade beingprocessed.5. Chemical Composition5.1 Chemical AnalysisChemical analysis of materials covered by this specification shall be in accordance with Test Methods,Practices, and Terminology A751.5.2 Heat Analysi
45、sAn analysis of samples obtained in accordance with 4.4 or Supplementary Requirement S20, as appropriate,shall be made by the manufacturer to determine the percentages of the elements specified in the individual specification for thegrade being poured. When drillings are used, they shall be taken no
46、t less than 116 in. 2 mm beneath the surface. The chemicalcomposition thus determined shall conform to the requirements in the individual specification for the grade being poured.5.3 Product AnalysisAproduct analysis may be made by the purchaser from material representing each master heat, sub-heat,
47、lot, or casting. The analysis shall be made on representative material. Samples for carbon analysis of carbon and alloy steel shallbe taken no closer than 116 in. 2 mm to a cast surface, except that castings too thin for this shall be analyzed on representativematerial. The chemical composition thus
48、 determined shall meet the requirements specified in the applicable specification for thegrade involved, or shall be subject to rejection by the purchaser, except that the chemical composition determined for carbon andlow alloy low-alloy steel and stainless steel castings may vary from the specified
49、 limits by the amounts shown in Tables 1 and 2,respectivel.respectively. The product analysis tolerances of Table 1 are not applicable as acceptance criteria for heat analysis bythe casting manufacturer. When comparing product and heat analysis for other than carbon and low alloy low-alloy steels, andstainless steels, the reproducibility Data R2, in Test Methods E353 or E354, as applicable, shall be taken into consideration.5.4 Unspecified ElementsWhen chemical analysis for elements not specified for the grade order
