1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 12576:1998 The Euro
2、pean Standard EN 12576:1998 has the status of a British Standard ICS 83.120; 83.140.10 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Plastics Fibre reinforced composites Preparation of compression moulded test plates of SMC, BMC and DMCThis British Standard, having been prep
3、ared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 November 1998 BSI 1998 ISBN 0 580 30021 8 BS EN 12576:1998 Amendments issued since publication Amd. No. Date Text affected National f
4、oreword This British Standard is the English language version of EN 12576:1998. The UK participation in its preparation was entrusted to Technical Committee PRI/42, Fibre reinforced thermosetting plastics and prepregs, which has the responsibility to: aid enquirers to understand the text; present to
5、 the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on reques
6、t to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the
7、 BSI Standards Electronic Catalogue. 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 of itself confer immunity from legal obligations. Summ
8、ary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 5 and a back cover.CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CE
9、N All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12576:1998 E EUROPEAN STANDARD EN 12576 NORME EUROPE ENNE EUROPA ISCHE NORM May 1998 ICS 83.120; 83.140.10 Descriptors: Plastics, reinforced plastics, plastic moulding, reinforcing mate
10、rials, thermosetting resins, composition: property, specimen preparation, plates, dimensions, procedures English version Plastics Fibre reinforced composites Preparation of compression moulded test plates of SMC, BMC and DMC Plastiques Composites renforce s de fibres Pre paration de plaque dessais d
11、e SMC, BMC et DMC pour moulage par compression Kunststoffe Fasversta rkte Verbundwerkstoffe Herstellung von formgepreten Pru fplatten aus SMC, BMC und DMC This European Standard was approved by CEN on 1 May 1998. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipula
12、te the conditions for giving this European Standard the status 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 exis
13、ts in three official versions English, French, German). 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 bodi
14、es of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.Page 2 EN 12576:1998 BSI 1998 Foreword This European Standard has been prepared by Technical Committee CEN/TC 249, Plas
15、tics, the Secretariat of which is held by IBN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 1998, and conflicting national standards shall be withdrawn at the latest by November 1998.
16、According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Por
17、tugal, Spain, Sweden, Switzerland and the United Kingdom. Compression moulding of SMC, BMC and DMC differs from all other compression mouldable reinforced thermoset materials. Because of the flowing characteristic of the reinforcing fibres and the typical maturation process before moulding, a partic
18、ular manufacturing method is specified for the fabrication of test plates. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Health and safety 3 5 Plate dimensions 3 6 Apparatus and equipment 3 7 Sampling and conditioning 4 8 Procedure 4 9 Stabilization 4 10 Manufacturing
19、 report 4 11 Precision 4 Annex A (informative) Bibliography 5 Annex B (informative) Applicable test methods 5Page 3 EN 12576:1998 BSI 1998 1 Scope This European Standard specifies the general principles and procedures for the preparation of compression moulded test plates from fibre reinforced therm
20、osetting moulding compounds such as sheet moulding compound (SMC), bulk moulding compound (BMC) and dough moulding compound (DMC). The purpose of this European Standard is to specify the preparation of flat test plates from which test specimens can be machined (for applicable test purposes see infor
21、mative annex A). Test plates are being manufactured to give representative results by the different test procedures using specimens machined out of these test plates. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These n
22、ormative references are cited at the appropriate places in the text and 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 refer
23、ences the latest edition of the publication referred to applies. EN 1842, Plastics Thermoset moulding compounds (SMC BMC) Determination of compression moulding shrinkage. EN ISO 12115:1997, Fibre-reinforced plastics Thermosetting moulding compounds and prepregs Determination of flowability, maturati
24、on and shelf life (ISO 12115:1997). ISO 472, Plastics Vocabulary. ISO 8604, Plastics Prepregs Definitions of terms and symbols for designations. 3 Definitions For the purposes of this European Standard the terms and definitions given in ISO 472 and ISO 8604 apply with the addition of the following d
25、efinitions. 3.1 pressing time period during a press cycle in which the mould is closed, and the required pressure is reached 3.2 elementary unit smallest normally commercially available entity of a given product NOTE The description (form, dimensions, mass, etc.) of the elementary unit will normally
26、 be defined in the product specification. Elementary unit can be supplied in the form of rolls or packages for instance. For a given product, the dimensions, mass or volume of the elementary unit can change, as manufacturing techniques evolve, without necessarily causing any modification in the prop
27、erties of the product or the way in which these properties vary within the elementary unit 4 Health and safety This European Standard limits itself to describing the preparation of compression moulded test plates. The handling conditions of the products and materials used shall comply with the natio
28、nal regulations in force in each country and the staff shall be informed of the risks involved and appropriate precautions taken. 5 Plate dimensions It is recommended to compression mould a plate of about 200 mm3 590 mm (see also Method II in EN ISO 12115). If no suitable mould is available a plate
29、with a minimum area of 450 cm 2 shall be produced to achieve at least five test specimens of 20 mm3 250 mm. Most of the test procedures for SMC, BMC and DMC require a thickness of the test specimen of about 4 mm. For particular test methods the moulded plate according to EN 1842 could also be used.
30、6 Apparatus and equipment 6.1 Press Test plates can be moulded on any hydraulic moulding press which complies with the following conditions: maintaining the specified pressure within 5% during pressing time; capable of being closed within 15 s prior to pressure build up. 6.2 Mould A mould for compre
31、ssion moulding shall be able to withstand the specified temperatures and pressures. The mould design shall ensure the entire force is applied to the moulding material. The mould cavity shall be flat and have an area of 450 cm 2 as a minimum (see also 5.22 of EN ISO 12115:1997 concerning Method II).
32、6.3 Cooling rack A nonmetallic cooling rack to hold samples vertically with a minimum spacing of 20 mm and two additional protective plates. To achieve symmetrical cooling for all test plates the outer lateral test plates shall be protected by additional protective plates.Page 4 EN 12576:1998 BSI 19
33、98 7 Sampling and conditioning An SMC sample shall be taken out of an elementary unit and of full width. The width shall be reduced from both sides by 5 cm each to prevent edge influences of the production process. From BMC or DMC a sample shall be taken out of the centre of an elementary unit. Imme
34、diately after sampling the material shall be protected by an appropriate bag to avoid variations of volatile contents and moisture absorption. Samples shall be conditioned to establish temperature equilibrium before moulding by placing them into a room with a temperature of 238C 28C. 8 Procedure 8.1
35、 Preparation of charge The mould coverage for SMC shall not be less than 90 % based on the total cavity area, unless other levels of the mould coverage are specified. The SMC charge is prepared by stacking the necessary number of SMC layers. To prevent orientation of fibres both the length and the w
36、idth are reduced in case of not using 100 % coverage. The reduction of length and width is of the same ratio. The stacked layers (SMC charge) shall be weighed and moulded immediately after preparation of the charge. Moulding materials like BMC and DMC shall be preformed to a homogenous charge prior
37、to moulding by shaping and dispersing as even as possible into an appropriate geometry on a flat tray and then directly loaded into the open mould. NOTE In the case of not being able to apply the provisions of 8.1 the top layer of the SMC charge can be of a smaller size compared to the others; the r
38、eduction of the size being perpendicular to the orientation of the test piece machined from the test plate. 8.2 Moulding conditions The mould temperature shall be 1403 (1 2% )8 C, unless other conditions are specified or agreed between user and supplier. The moulding material shall be put into the o
39、pen mould and the mould shall be closed within 15 s. According to the type of material the pressure to be applied as well as the pressing time shall follow the respective material specification. 8.3 Moulding procedure 8.3.1 Select the moulding conditions to be used. 8.3.2 Prepare the charge to obtai
40、n the specified thickness of the flat test plate according to 8.1. 8.3.3 Weigh the material. 8.3.4 Load the prepared charge into the centre of the mould cavity and close the press. Check if closing time is within the specification. After closing, and as soon as the specified pressure is reached, the
41、 pressing time measurement shall start. 8.3.5 When the pressing time is completed, open the press, remove the moulded part and place it into the cooling rack for cooling to room temperature. 8.3.6 Check that the moulding is satisfactory and does not exhibit any faults which might affect further test
42、ing operations. 8.3.7 Measure the thickness. 9 Stabilization Unless otherwise stated, it is recommended to keep the test plates for 48 h in the laboratory atmosphere before cutting the test specimens from the manufactured plates. The conditioning of test specimens is given in the particular testing
43、standard. 10 Manufacturing report The report shall include the following details: reference to this European Standard; complete identification of the material tested, including at least type, source, manufacturers name and designation; date of manufacturing; number of elementary units; type of press
44、; type and size of mould used; description of charge (length, width, weight and number of SMC layers, weight of BMC/DMC; moulding conditions (temperature, pressure, pressing time); number and thickness of test plates; observations on any circumstances liable to influence the moulding results. 11 Pre
45、cision The precision of this procedure is not known because interlaboratory data are not available. When interlaboratory data are obtained, a precision statement will be added with the next revision.Page 5 EN 12576:1998 BSI 1998 Annex A (informative) Bibliography EN ISO 12114, Fibre-reinforced plast
46、ics Thermosetting moulding compounds and prepregs Determination of cure characteristics (ISO 12114:1997). ISO 295, Plastics Compression moulding of test specimens of thermosetting materials. Annex B (informative) Applicable test methods Test specimens machined out of test plates according to this Eu
47、ropean Standard, can be used for the following test methods: B.1 Mechanical properties EN ISO 178, Plastics Determination of flexural properties. EN ISO 179, Plastics Determination of Charpy impact strength. EN ISO 180, Plastics Determination of Izod impact strength. EN ISO 527-1, Plastics Determina
48、tion of tensile properties Part 1: General principles. EN ISO 527-2, Plastics Determination of tensile properties Part 2: Test conditions for moulding and extrusion plastics. EN ISO 6603-1, Plastics Determination of multiaxial impact behaviour of rigid plastics Part 1: Falling dart method. EN ISO 66
49、03-2, Plastics Determination of multiaxial impact behaviour of rigid plastics Part 2: Instrumented puncture test. B.2 Thermal properties EN ISO 75-1, Plastics Determination of temperature of deflection under load Part 1: General test method. EN ISO 75-2, Plastics Determination of temperature of deflection under load Part 2: Plastics and ebonite. EN ISO 75-3, Plastics Determination of temperature of deflection under load Part 3: High-strength thermosetting
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