1、BRITISH STANDARD AEROSPACE SERIES BS EN 2858-2:1994 Titanium and titanium alloys Forging stock and forgings Technical specification Part2: Forging stock The European Standard EN2858-2:1994 has the status of a BritishStandard UDC 669.295-4:621.73:620.1:629.7BSEN2858-2:1994 This BritishStandard, havin
2、g been prepared under the directionof the Aerospace Standards Policy Committee, waspublished under the authorityof the Standards Boardand comes into effect on 15July1994 BSI12-1999 The following BSI references relate to the work on this standard: Committee reference ACE/61 Draft for comment93/707236
3、 DC ISBN 0 580 22391 4 Cooperating organizations The European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge
4、 de normalisation Denmark Dansk Standardiseringsraad Finland Suomen Standardisoimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standard
5、s Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Swede
6、n Standardiseringskommissionen i Sverige Switzerland Association suisse de normalisation United Kingdom BritishStandards Institution Amendments issued since publication Amd. No. Date CommentsBSEN2858-2:1994 BSI 12-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii
7、 Foreword 2 1 Scope 3 2 Normative references 3 3 Manufacture 3 4 Dimensions and tolerances 5 5 Internal defects 5 6 External defects 5 7 Alloy verification 5 8 Metallographic examination 5 9 Mechanical testing 6 10 Special tests 6 11 Traceability 6 12 Marking 6 National annex NA (informative) Commit
8、tees responsible Inside back cover National annex NB (informative) Cross-references Inside back cover Table 1 5 Table 2 Summary of requirements 7 Table 3 Limits of scrap utilization 8BSEN2858-2:1994 ii BSI 12-1999 National foreword This BritishStandard has been prepared under the direction of the Ae
9、rospace Standards Policy Committee and is the English language version of EN2858-2:1994, Aerospace series. Titanium and titanium alloys. Forging stock and forgings. Technical specifications. Part2: Forging stock, published by the European Committee for Standardization (CEN). EN2858-2:1994 was produc
10、ed as a result of international discussion in which the United Kingdom took an active part. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not
11、 of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN title page, pages2 to8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorpo
12、rated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2858-2 April1994 UDC: 669.295-4:621.73:620.1:629.7 Descriptors: Aircraft industry, titanium, titanium alloys, forgings, specifications English version Aerospace series
13、Titanium and titanium alloys Forging stock and forgings Technical specification Part2: Forging stock Srie arospatiale Titane et alliages de titane Produits destins la forge, pices forges et pices matrices Spcification technique Partie2Produits destins la forge Luft-und Raumfahrt Titan und Titanlegie
14、rungen Schmiedevormaterial und Schmiedestcke Technische Lieferbedingungen Teil2Schmiedevormaterial This European Standard was approved by CEN on1994-04-27. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the s
15、tatus of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German).
16、A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, German
17、y, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyrig
18、ht reserved to CEN members Ref.No.EN2858-2:1994EEN2858-2:1994 BSI 12-1999 2 Foreword This European Standard has been prepared by the European Association of Aerospace Manufacturers (AECMA). After inquiries and votes carried out in accordance with the rules of this Association, this standard has succ
19、essively received the approval of the National Associations and the Official Services of the member countries of AECMA, prior to its presentation to CEN. This standard was submitted for Formal Vote, and the result was positive. This European Standard shall be given the status of a national standard,
20、 either by publication of an identical text or by endorsement, at the latest by October1994, and conflicting national standards shall be withdrawn at the latest by October1994. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: A
21、ustria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EN2858-2:1994 BSI 12-1999 3 1 Scope This standard specifies the particular requirements for forging stock of grades1 1)and2 2)
22、intended to be used for the manufacture of titanium and titanium alloy forgings. Unless otherwise specified, the requirements for grade2 shall apply. This standard shall be used in conjunction with EN2858-1. Bars and sections to EN3544-3 may be used as forging stock provided that an agreement has be
23、en established between the forging stock manufacturer 3)and the purchaser to ensure that the requirements of this standard are met. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at th
24、e appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
25、 publication referred to applies. EN2002-1, Aerospace series Test methods for metallic materials Part1: Tensile testing at ambient temperature 4) . EN2002-2, Aerospace series Test methods for metallic materials Part2: Tensile testing at elevated temperature 4) . EN2002-5, Aerospace series Test metho
26、ds for metallic materials Part5: Uninterrupted creep and creep rupture testing 4) . EN2003-8, Aerospace series Test methods for products in steel, titanium, titanium alloys, aluminium alloys and heat resisting alloys Part8: Ultrasonic inspection of billets, bars, plates and forgings 5) . EN2858-1, A
27、erospace series Titanium and titanium alloys Forging stock and forgings Technical specification Part1: General requirements. EN2954-2, Aerospace series Macrostructure of titanium alloy wrought products Part2:Macrostructure of bar, section, forging stock and forgings 5) . EN2955, Aerospace series Rec
28、ycling of titanium and titanium alloy scrap. EN2957, Aerospace series Method of preparation of forged samples 4) . EN3114, Aerospace series Test methods for titanium + products Micrographic examination 5) . EN3544-3, Aerospace series Titanium and titanium alloys Wrought products Technical specificat
29、ion Part3: Bar and section 5) . 3 Manufacture 3.1 Raw materials 3.1.1 General requirements for grades1 and2 forging stock Raw materials shall be only purchased from suppliers approved by the manufacturer and registered in his list of approved suppliers. Approval of suppliers shall be made in accorda
30、nce with written procedures contained within the quality assurance system of the manufacturer. 3.1.2 Titanium sponge and alloying elements The requirements shall be specified by the manufacturer who shall also establish the following procedures for: titanium sponge: level of impurities, particle siz
31、e, freedom from surface contamination; alloying elements: chemical composition including level of impurities, particle size, freedom from foreign particles. 3.1.3 Recycling of scrap Requirements for processing and categorization of scrap are defined in EN2955. The categories of scrap which may be us
32、ed by the manufacturer are given in Table 3. Foundry scrap, castings or used components shall not be used. The manufacturer shall maintain a list of his approved scrap processors. The list shall indicate the categories of scrap for which the processors are approved. Each order shall refer to EN2955,
33、 specify the sub-category of the scrap and, in the case of turnings, the limits forO 2 , C and H 2 . 1) Corresponds to Disc Quality (DQ) in European Titanium Technical Committee (ETTC) Publication No.5, February1983 2) Corresponds to Standard Quality (STQ) in European Titanium Technical Committee (E
34、TTC) Publication No.5, February1983 3) Hereafter called “manufacturer” 4) Published as AECMA Prestandard at the date of publication of this standard 5) In preparation at the date of publication of this standardEN2858-2:1994 4 BSI 12-1999 3.1.4 Additional requirements for grade1 forging stock Recycli
35、ng procedures and the raw materials suppliers shall have been approved by the forger and the purchaser of the forgings. Any modifications shall be the subject of prior agreement by the forger and the purchaser of the forgings. All incoming supplies shall be quarantined until the acceptance requireme
36、nts have been satisfactorily completed. A manufacturing schedule for forging stock shall be established. It shall indicate the sub-category and the maximum of approved scrap to be used in the melt and shall be approved by the purchaser of the forgings. 3.2 Electrodes 3.2.1 General requirements for g
37、rade1 and2 forging stock 3.2.1.1 The melter shall establish procedures for the charge make up of each type of electrode which shall include: scrap categories to be used; distribution of scrap along the electrode; electrode build-up and welding; requirement for recording the constitution of each char
38、ge. The scrap shall be of the same alloy. Unalloyed titanium scrap may also be used provided individual pieces do not exceed approximately20g. Build-up of electrodes and attachment to their stubs shall be carried out under vacuum or inert gas in accordance with the procedure defined by the manufactu
39、rer. 3.2.1.2 Welding Primary electrode: The welding methods to be used are: MIG, plasma or electron beam. Electrode for remelting: The welding methods to be used for joining electrodes are: plasma in a chamber under argon or electric arc in a vacuum furnace. Stub: The welding methods to be used are:
40、 MIG, plasma in a chamber under argon or electric arc in a vacuum furnace. Welds shall be visually examined to verify the absence of unacceptable colouring in accordance with the standard defined by the manufacturer. 3.2.2 Additional requirements for grade1 forging stock All welding shall be carried
41、 out in a vacuum chamber with leak rate control, or in a chamber under argon overpressure, with continuous checking of oxygen content. 3.3 Melting 3.3.1 General requirements for grades1 and2 forging stock Scrap may only be used during the first melt, except for striking the arc. The forging stock sh
42、all be vacuum melted at least twice. The final melt shall use a consummable electrode. The stub weld interface shall not be melted unless the stub is of the same alloy and same grade and the weld has been made without filler metal, in a vacuum or argon environment. Arc breaks during the final meltin
43、g operation shall not exceed60s. An appropriate system shall be provided for the control, checking and verification for the current, voltage, pressure and melting rate. The manufacturer shall establish written procedures which define: the cleaning of furnace and ingot-moulds; the purity of the argon
44、 used, the current, the voltage and the maximum allowed pressure during melting; the maximum allowed leak rate in the furnace; the hot topping cycle at the end of the final melt; the inspection of the stub weld interface. 3.3.2 Additional requirements for grade1 forging stock Only melting furnaces w
45、hich are designated in the manufacturing schedule shall be used. A minimum of two consummable electrode remelting cycles under vacuum shall be applied. In case of triple melting, the first operation may be a non consummable electrode vacuum melting with the agreement of the purchaser of the forgings
46、. Each electrode weld shall be subjected to a minimum of two melting operations. Arc breaks during the final melting operation shall not exceed30s. An appropriate system shall be provided for the control, checking and verification of each operation. Any modification to the procedure shall be the sub
47、ject of prior agreement by the forger and the purchaser of the forgings.EN2858-2:1994 BSI 12-1999 5 3.4 Mechanical hot-working 3.4.1 General requirements for grades1 and2 forging stock Unless otherwise specified in the order or the manufacturing schedule, all forging stock shall be worked by drawing
48、 and/or upsetting with a minimum cross-section ratio3:1. The ratio may be obtained by several methods, including upsetting; in this case, the final ratio shall be the product of each individual ratio. The manufacturer shall establish procedures for the homogenization, preheating, transfer and mechan
49、ical working of ingots, which shall include the time periods. All forging stock shall be finally machined or ground to remove surface contamination and to a finish which will allow the satisfactory performance of the inspection operation specified. 3.4.2 Additional requirements for grade1 forging stock Any modification to the mechanical working procedures shall be the subject of prior agreement by the forger and the purchaser of the forgings. 4 Dimensions and tolerances
