1、CEN PREN*E858 PART*2 93 m 3404589 0044b02 bT9 m Approved by COMITE DE NORMALISATION of A.E.C.M.A. 1993-04-26 A.E.C.M.A. STANDARD NORME A.E.C.M.A. A.E.C.M.A. NORM The equivalent vdom m French and German bngiages can be supplied by B.N.A.E. - Technopolis 54 - 199, rue JeamJacques Rousseau 92138 ISSY -
2、 LES - MOULINEAUX CEDEX prEN 2858 Part 2 Edition 1 April 1993 EDITE PAR LASSOCIATION EUROPEENNE DES CONSTRUCTEURS DE MATERIEL AEROSPATIAL Technopolis - 175, rue JeamJacques Rousseau - F-92138 Issy-les-Moulineaux Cedex - Tl. (1) 47.36.98.76 UDC : Key words : ENGLISH VERSION Aerospace series Titanium
3、and titanium alloys Forging stock and forgings Technical specification Part 2 - Forging stock Srie arospatiale Titane et alliages de titane Produits destins la forge, pices forges et pices matrices Spcification technique Partie 2 - Produits destin - distribution of scrap along the electrode; - elect
4、rode build-up and welding: - requirement for recording the constitution of each charge. CEN PRENx2858 PART*2 73 = 3404589 0044bOb 244 prEN 2858-2 Page 5 The scrap shall be of the same alloy. Unalloyed titanium scrap may also be used provided individual pieces do not exceed approximately 20 g. Build-
5、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 manufacturer. 3.2.1.2 Welding - Primary electrode : The welding methods to be used are : MIG, ,plasma or electron beam. - Electrode for remelting : The weldin
6、g 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 : MIG, plasma in a chamber under argon or electric arc in a vacuum furnace. Welds shall be visually examined to verify the absence of una
7、cceptable colouring in accordance with the standard defined by the manufacturer. 3.2.2 Additional requirements for grade 1 forging stock All welding shall be carried out in a vacuum chamber with leak rate control, or in a chamber under argon overpressure, with continuous checking of oxygen content.
8、3.3 Melting 3.3.1 General requirements for grades 1 and 2 forging stock Scrap may only be used during the first melt, except for striking the arc. The forging stock shall be vacuum melted at least twice. The final melt shall use a consummable electrode. The stub weld interface shall not be melted un
9、less 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 melting operation shall not exceed 60 s. An appropriate system shall be provided for the control, checking and verification for the current
10、, 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 used, the current, the voltage and the maximum allowed pressure during - the maximum allowed leak rate in the furnace; - the
11、hot topping cycle at the end of the final melt; - the inspection of the stub weld interface. melting; CEN PREN*2858 PARTt2 93 m 3qOq589 00q4b07 180 m prEN 2858-2 Page 6 3.3.2 Additional requirements for grade 1 forging stock Only melting furnaces which are designated in the manufacturing schedule sh
12、all 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. Each electrode weld shall be subjected to a minimu
13、m of two melting operations. Arc breaks during the final melting operation shall not exceed 30 s. An appropriate system shall be provided for the control, checking and verification of each operation. Any modification to the procedure shall be the subject of prior agreement by the forger and the purc
14、haser of the forgings. 3.4 Mechanical hot-working 3.4.1 General requirements for grades 1 and 2 forging stock Unless otherwise specified in the order or the manufacturing schedule, all forging stock shall be worked by drawing and/or upsetting with a minimum cross-section ratio 3 : 1. The ratio may b
15、e 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 mechanical working of ingots, which shall include the time periods. All forgi
16、ng 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 grade 1 forging stock Any modification to the mechanical working procedures shall be the
17、 subject of prior agreement by the forger and the purchaser of the forgings. 4 Dimensions and tolerances Dimensions and tolerances shall be defined by the order. The frequency of examination adopted by the manufacturer shall be sufficient to permit him to certify compliance with the requirements. CE
18、N PRENx2858 PART*2 93 W 3404589 0044b08 017 prEN 2858-2 Page 7 Thickness mm s 100 5 Internal defects Grade 1 I Grade 2 6 I 5 Class After surface preparation, the full volume of the forging stock shall be ultrasonically inspected in accordance with EN 2003-8 and table 1 : 100 C De S 200 200 C De S 30
19、0 300 Table 1 5 4 5 3 4 3 6 External defects 6.1 General requirements for grades 1 and 2 forging stock The forging stock surface shall be free from defects considered as prejudicial to further working. If required by the forger, the forgeability shall be verified by forged samples (see 9). Surface d
20、efects may be removed by local dressing up to 3% of the nominal thickness. Dressing shall be smoothly blended and shall allow an ultrasonic examination. Each product shall be visually examined after etching. 6.2 Additional requirements for grade 1 forging stock Local dressing is not permitted prior
21、to ultrasonic testing. If ultrasonic testing of the full volume can be completed satisfactorily, local dressing up to a maximum of 3% of the nominal thickness is permitted after ultrasonic testing. If ultrasonic testing cannot be completed satisfactorily, the whole surface shall be machined. 7 Alloy
22、 verification Each product shall be inspected to verify alloy type before dispatch. The method used shall be at the discretion of the manufacturer. 8 Metallographic examination Samples shall be etched and subjected to macrographic examination in accordance with EN 2954-2. Additionally, for a + alloy
23、s, micrographic examination shall be carried out in accordance with EN 31 14. Transverse slices shall be taken from forging stock at locations corresponding to the top and the bottom of the original ingot. CEN PRENa2858 PART+2 93 3404589 0044b09 T53 prEN 2858-2 Page 8 9 Mechanical testing When requi
24、red by the material standard or order, testing shall be carried out in accordance with 9.1 to 9.3. Test samples shall be cut from forging stock in an area corresponding to the top of the originally ingot. Test pieces shall be machined without further deformation of the samples or after forging in ac
25、cordance with EN 2957. 9.1 Tensile testing at room temperature It shall be performed to EN 2002-1 on proportional round test pieces. The form and size shall be selected from EN 2002-1. The frequency shall be as indicated in table 2. The results shall comply with the requirements of the material stan
26、dard. 9.2 Tensile testing at elevated temperature It shall be performed to EN 2002-2 on proportional round test pieces. The form and size shall be selected from EN 2002-2. The frequency shall be as indicated in table 2. The results shall comply with the requirements of the material standard. 9.3 Uni
27、nterrupted creep and creep rupture testing They shall be performed to EN 2002-5 on proportional round test pieces. The form and size shall be selected from EN 2002-5. The frequency shall be as indicated in table 2. The results shall comply with the requirements of the material standard. 10 Special t
28、ests Special tests and inspections may be required by the purchaser. In each case, after agreement between the purchaser and manufacturer, the nature of test, methods, frequency of tests and acceptance criteria shall be specified on the order or in the inspection schedule. 11 Traceability 1 1.1 Gene
29、ral requirements for grades 1 and 2 forging stock See EN 2858-1. 1 1.2 Additional requirements for grade 1 forging stock Complete traceability is required including the operations performed and the raw materials used. CEN PRENx2858 PART*2 93 = 3YOY5 OOYYbLO 775 = prEN 2858-2 Page 9 12 Marking Each f
30、orging stock shall bear the following identification marking : - material standard number; - castfingot number; - forging stock identification number, when required; - delivery condition if heat treatment is required by the order; - identification of manufacturer and, where appropriate, of plant; -
31、inspection stamp. Identification marking shall be : - hard stamped at least once on each forging stock 2 20 mm, - on a durable label for forging stock e 20 mm supplied in bundles. CEN PRENW858 PARTW 93 = 3VOV589 OOV4bLL bOL prEN 2858-2 Page 10 v) C c, E al =I U L .- 2 2 E Y- O E 3 m N al 2 CEN PREN82858 PART82 93 3404589 00446l12 548 -! +-? *e m U O T - c! t prEN 2858-2 Page 11 o) 9 C 0 U
