1、 STD-BSI BS EN L257b-ENGL 1778 1b2qbbS 0732b73 2bT H BRITISH STANDARD Plastics - Fibre reinforced composites - Preparation of compression moulded test plates of SMC, BMC and DMC The European Standard EN 125761998 has the status of a British Standard ICs 83.120; 83.140.10 BS EN 12576:1998 NO COPYING
2、WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW STDmBSI BS EN L257b-ENGL 1998 lb24bb9 0732b74 LTb = been prepared under the direction of the Sector Amd.No. (ommttee for Matenais and Chemicals, was published under the authonty of the Standards Committee and comes into effect on 15 Novembe
3、r 1998 C BSI 1998 ISBN O 580 30021 8 BS EN 12576:1998 Date Text affected National foreword Tkis British Standard is the English language version of EN 12576:1998. The UK participation in its preparation was entnisted to Technical Conunittee PRV42, Fibre reinforced thermosetting plastics and prepregs
4、, which has the responsibility to: - aid enquirers to understand the text; - present to the responsible European cominittee any enquiries on the - monitor related international and European developments and promulgate interpretation, or proposals for change, wd keep the UK interests infonned them in
5、 the UK. A list of organizations represented on this conimittee can be obtained on request to its secretaxy. 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 entitl
6、ed “International Standards Correspondence Index”, or by using the “Find” fachty of the 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
7、with a British Standard does not of itself confer immunity from legal obligations. Summary of pages Thic document comprises a front cover, an inside front cover, the EN title page, pages 2 to 5 and a back cover. STD-BSI BS EN L257b-ENGL 1776 LbZLibbS 0732b95 032 EUROPEAN STANDARD EN 12576 NORME EURO
8、PENNE EUROP- NORM May 1998 ICs 83.120 83.140.10 Descriptors: Plastics, reinforced plastics, plastic moulding, reinforcing materials, thermosetting resins, composition: property, specimen preparation, plates, dimensions, procedures English version PMcs - Fibre reinforced composites - Preparation of c
9、ompmsion moulded test plates of SMC, BMC and DMC Plastiques - Composites renforcs de fibres - Prpamtion de plaque dessais de SMC, BMC et DMC pour moulage par compression Kunststoffe - Fasverstarkte Verbunwerkstoffe - Herstellung von formgepreBten pnifplatten aus SMC, BMC und DMC This European Standa
10、rd was approved by CEN on 1 May 1998. CEN members are bound to comply with the CENKENELEC Intmal Regulations which stipdak the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date iists and bibliographical references concerning such nation
11、al 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). A version in any other language made by translation under the responsibility of a CEN member into its own language and notif
12、ied to the Central Secretanat has the same status as the officiai versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, hce, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norwax Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN
13、 European Committee for Standardizahon Comit Europen de Normalisation Europisches Komitee fur Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 125761998 E STD-B
14、SI BS EN L257b-ENGL 1998 D LbZLibbS 0732b9b T77 D Page 2 EN 125761998 Foreword This European Standard has been prepared by Technical Committee CENRC 249, Plastics, the Secretariat of which is held by IBN. This European Standaxd shall be given the status of a national standard, either by publication
15、of am identical text or by endorsement, at the latest by November 1998, and conflicting national standards shall be withdrawn at the latest by November 1998. Accorduig to the CENICENELEC Internal Regulations, the national ctandasdc organizations of the following countries are bound to implement this
16、 European Standard Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Iay, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Compression moulding of SMC, BMC and DMC differs from all other compression mouldable r
17、einforced thermoset materials. Because of the flowing characteristic of the reinforcing fibres and the typical maimation process before moulding, a particular manufacturing method is specified for the fabrication of test plates. Contents Foreword 1 Scope 2 Normative references 3 Definitions 4 Health
18、 arid safety 5 Plate dimensions 6 Apparatus and equipment 7 Sampling and conditioning 8 Procedure 9 Stabilization 10 Manufacturing report 11 Precision Annex A (informative) Bibliography Annex B (informative) Applicable test methods Page 2 3 3 3 3 3 3 4 4 4 4 4 5 5 n m n STD-BSI BS EN L257b-ENGL L978
19、 Lb24bb9 0732b97 905 Page 3 EN 126761998 1 scope This European Standard specifies the general principles and procedures for the preparation of compression moulded test plates from fibre reinforced thennosetting moulding compounds such as sheet moulding compound (SMC), bulk moulding compound (BMC) an
20、d dough moulding compound (DMC). The purpose of this European Standard is to spec the preparation of fiat test plates from which test specimens can be machined (for applicable test purposes see informative annex A). %st plates are being manufactured to give representative results by the different te
21、st 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 nonnative references are cited at the appropriate places in the text and publications are listed hereaf
22、ter. 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 akst edition of the publication referred to applies. EN 1842, Plastics - Thmmset moulding co
23、mpounds (SMC - BMC) - Determination of compression moulding shrnkage. EN IS0 121151997, Fibre-reinforced plastics - Thermosetting moulding compounds and prepregs - Determination of jbwabdity, rnuturation and shelf Lfe (IS0 121151997). IS0 472, Plastis - Voca.bulaq IS0 8604, Rastics - hepregs - Defzn
24、tions of terms and symbols for des.ignatwns. 3 Definitions For the purposes of this European Standard the terms and definitions given in IS0 472 and IS0 8604 apply with the addtion of the following definitions. 3.1 pressing time period during a press cycle in which the mould is closed, and the requi
25、red 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 be defined in the product specification. Elementary unit can be supplied in the form of rolls or pac
26、kages 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 modifcation in the properties of the product or the way in which these properties vary within the elementary unit 4 Health an
27、d safety This European Standard limits itself to describing the preparation of compression moulded test plates. The handing conditions of the products and materials used shail comply with the national regulations in force in each country and the staff shall be informed of the risks involved and appr
28、opriate precautions taken. 6 Plate dimensions It is recommended ta compression mould a plate of about 200 mm X 590 mm (see also Method II in EN IS0 12115). If no suitable mould is available a plate with a minimum area of 450 cm2 shall be produced to achieve at least five test specimens of 20 mm X 25
29、0 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. 6 Apparatus and equipment 6.1 Press Test plates can be moulded on any hydmulic moulding press which co
30、mplies with the following conditions: - maintaining the specified pressure within % % during pressing time; - capable of being closed within 15 s prior to pressure build up. 6.2 Mould A mould for compression moulding shall be able to withstand the specified temperatures and pressures. The mould desi
31、gn shall ensure the entire force is applied to the moulding matenal. The mould cavity shd be flat and have an area of 450 cm2 as a minimum (see also 6.22 of EN IS0 121151997 concerning Method Ii). 6.3 Cooling rack A nonmetallic cooling rack to hold samples vertically with a minimum spacing of 20 mm
32、and two additional protective plates. To achieve symmetrical cooling for ali test plates the outer laterai test plates shal be protected by additional protective plates. O BSI 1998 STD-BSI BS EN L257b-ENGL 1798 D Lb29bb7 0732b78 841 D Page 4 EN 125761998 7 Sampling and conditioning An SMC sample sha
33、ll be taken out of an elementasy 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 elementasy unit. immediately after sampling the material shall be pro
34、tected 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 23 “C f 2 “C. 8 Procedure 8.1 Preparation of charge The mould coverage fo
35、r SMC shall not be les 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 width are reduced in case of not using 100 % c
36、overage. 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 pnor to moulding by shaping and dispersing as even
37、as possible into an appropriate geometry on a fiat by and then directly loaded into the open mould. NOTE In the case of not being able lo apply the promions of 8.1 the top layer of the SMC charge can be of a smaller size compared to the others, the reduction of the size being perpendicular to the on
38、entation of thv test piece machined from the test plate 8.2 Moulding conditions The mould temperature shall be 140 X (1 f 2 %) OC, unless other conditions are specified or agreed between user and supplier. The mouldmg material shall be put into the open mould and the mould shall be closed within 15
39、s. According to the type of material the pressure to be applied as well as the pressing tune 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 obtain the specified thickness of the flat test plate ac
40、cording 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 pres. Check if closing time is within the specification. After closing, and as soon as the specified pressure is reached, the pressing tinie measurement shall start. 8.3.5 When
41、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 testing operations. 8.3.7 Measure the thickness. 9 Stab
42、ilization Unies 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 standard. 10 Manufacturing report The report shall i
43、nclude 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; - type and size of mould used - descripti
44、on of ctiarge (length, width, weight and number of SMC layers, weight of BMCDMC; - moulding conditions (temperature, pressure, pressing time); - number and thickness of test plates; - observations on any circumstances liable to influence the moiilding results. 11 Precision The precision of this proc
45、edure is not known because interlaboratory data are not available. When interlaboratory data are obtained, a precision statement will be added with the next revision. STD-BSI BS EN L257b-ENGL 1998 LbZlbbS 0732b79 788 9 Page 5 EN 12576:1998 Annex A (informative) Bibliography EN IS0 12114, Fibre-reinf
46、orced plastics - Themnosetting moulding mpounds and Irrepregs - Determination of cum chmteristics IS0 295,Ru.stics - Compression moulding of test specimens of themZ0settin.g materials. O 121141997). Annex B (informative) Applicable test methods %t specimens machined out of test plates according to t
47、his European Standard, can be used for the following test methods: B.l Mechanical properties EN IS0 178, pyclstics - Determination of jkmd PWh. EN IS0 179, plastics - Determination of clzarpy impact strength. EN IS0 180, plastics - Determination of Izod impcxt strength. EN IS0 527-1, plastics -Deter
48、mination of tensile pperth - Pari 1: Geneml principles. EN IS0 527-2, plastics - Determination of tensile pperth - Pa,rt 2: Test conditions for moulding and mtmwn pustics. multiaxial impact behaviour of rigid plastics - Part 1: Faing dart method. EN IS0 660%2, Plastics -Determination of multiarid im
49、pact behviour of rgid plastics - Part 2: Imtrumted puncture test. B.2 Thermal properties EN IS0 75-1, plastics - Detmrninatwn of temperature of dejection undm load -Part 1: Geneml test method. EN IS0 752, Plastics - Determination of temperature of &$ation under load - Part 2: Plastics and ebonite. EN IS0 753, Plastics - Determination of temperature of dejection u.nder load - Pari 3: High-strength UtemLosetting laminates and long-fibre-reinforced plastics. B.3 Chemical and physical properties IS0 62, Plastics -Determination of water absorption. IS0 1183, Pl
