ISO-1268-11-2005.pdf

Reference number ISO 1268-11:2005(E) © ISO 2005 INTERNATIONAL STANDARD ISO 1268-11 First edition 2005-02-01 Fibre-reinforced plastics Methods of producing test plates Part 11: Injection moulding of BMC and other long-fibre moulding compounds Small plates Plastiques renforcés de fibres Méthodes de fabrication de plaques d'essai Partie 11: Moulage par injection de BMC et d'autres mélanges à mouler à longues fibres Plaques de petites dimensions ISO 1268-11:2005(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. © ISO 2005 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii © ISO 2005 All rights reserved ISO 1268-11:2005(E) © ISO 2005 All rights reserved iii Contents Page Forewordiv Introduction v 1 Scope1 2 Normative references .1 3 Terms and definitions.1 4 Apparatus.1 5 Procedure.4 6 Report on test-specimen preparation.6 Annex A (informative) Recommended applications for small-plate test specimens or parts thereof7 Annex B (informative) Weld lines8 Annex C (informative) Marking of test specimens9 Bibliography .11 -,-,- ISO 1268-11:2005(E) iv © ISO 2005 All rights reserved Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 1268-11 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 13, Composites and reinforcement fibres. Together with the other parts (see below), this part of ISO 1268 cancels and replaces ISO 1268:1974, which has been technically revised. ISO 1268 consists of the following parts, under the general title Fibre-reinforced plastics Methods of producing test plates: Part 1: General conditions Part 2: Contact and spray-up moulding Part 3: Wet compression moulding Part 4: Moulding of prepregs Part 5: Filament winding Part 6: Pultrusion moulding Part 7: Resin transfer moulding Part 8: Compression moulding of SMC and BMC Part 9: Moulding of GMT/STC Part 10: Injection moulding of BMC and other long-fibre moulding compounds General principles and moulding of multipurpose test specimens Part 11: Injection moulding of BMC and other long-fibre moulding compounds Small plates -,-,- ISO 1268-11:2005(E) © ISO 2005 All rights reserved v Introduction Many factors in the injection-moulding process can influence the properties of moulded test specimens and hence the measured values obtained when the specimens are used in a test method. The thermal and mechanical properties of such specimens are in fact strongly dependent on the conditions of the moulding process used to prepare the specimens. Exact definition of each of the main parameters of the moulding process is a basic requirement for reproducible and comparable operating conditions. It is important in defining moulding conditions to consider any influence the conditions may have on the properties to be determined. Thermosets may show differences in orientation and length of anisotropic fillers such as long fibres and in curing. Residual (“frozen-in”) stresses in the moulded test specimens may also influence properties. Due to the crosslinking of thermosets, molecular orientation is of less influence on mechanical properties than it is for thermoplastics. Each of these phenomena must be controlled to avoid fluctuation of the numerical values of the measured properties. The principles described in this part of ISO 1268 are the same as those in ISO 10724-2. Only a few details of the moulds have changed, as has specimen thickness, because of the use of long-fibre reinforcements. It is therefore possible to compare the properties of long-fibre moulding compounds with those of thermosetting powder moulding compounds (PMCs) and thermoplastics. -,-,- -,-,- INTERNATIONAL STANDARD ISO 1268-11:2005(E) © ISO 2005 All rights reserved 1 Fibre-reinforced plastics Methods of producing test plates Part 11: Injection moulding of BMC and other long-fibre moulding compounds Small plates 1 Scope This part of ISO 1268 specifies two two-cavity moulds, designated the type D1 and type D2 ISO moulds, for the injection moulding of small plates measuring 60 mm × 60 mm with preferred thicknesses of 2 mm (type D1) or 4 mm (type D2) which can be used for a variety of tests (see Annex A). The moulds may additionally be fitted with inserts for studying the effects of weld lines on the mechanical properties (see Annex B). This part of ISO 1268 is intended to be read in conjunction with ISO 1268-1. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 472, Plastics Vocabulary ISO 1268-1, Fibre-reinforced plastics Methods of producing test plates Part 1: General conditions ISO 1268-10:2005, Fibre-reinforced plastics Methods of producing test plates Part 10: Injection moulding of BMC and other long-fibre moulding compounds General principles and moulding of multipurpose test specimens ISO 2577, Plastics Thermosetting moulding materials Determination of shrinkage 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 472 and ISO 1268-10 apply. 4 Apparatus 4.1 Type D1 and D2 ISO moulds Type D1 and D2 moulds are two-cavity moulds (see Figure 2) intended for the preparation of plates measuring 60 mm × 60 mm. The plates produced using these moulds shall have the dimensions given in Figure 1. ISO 1268-11:2005(E) 2 © ISO 2005 All rights reserved Key Sp sprue G gate R runner P pressure sensor Dimensions in mm Dimensions in mm l length of plate 60 ± 2 a hG height of gate (0,75 ± 0,05) × h b,c b width of plate 60 ± 2 a lR length of runner 25 to 30 d h thickness of plate: bR width of runner at gate W (b + 6) type D1 mould 2,0 ± 0,1 hR depth of runner at gate = h type D2 mould 4,0 ± 0,1 a l* unspecified distance lG length of gate 4,0 ± 0,1 b lp distance of pressure sensor 5 ± 2 e from gate a These dimensions are for the preferred test specimen used in ISO 6603. b See Note 1 to Subclause 4.1. c See Note 2 to Subclause 4.1. d See Note 3 to Subclause 4.1. e The position of the pressure sensor shall be further limited by the following conditions: lp + rp u 10 lp rp W 0 where rp is the radius of the sensor. Figure 1 Details of type D1 and D2 ISO moulds ISO 1268-11:2005(E) © ISO 2005 All rights reserved 3 Key Sp sprue G gate lC is the distance between the lines along which the test specimens are cut from the runners (see Note 4 to Subclause 4.1) moulding volume VM 30 000 mm3 (at 2 mm thickness) projected area Ap 11 000 mm2 Figure 2 Cavity plate for type D1 and D2 ISO moulds The main constructional details of type D1 and D2 ISO moulds shall be as shown in Figures 1 and 2 and shall meet the following requirements: a) The sprue diameter on the nozzle side shall be at least (4,5 ± 0,5) mm. b) The cavities shall be one-end gated as shown in Figure 2. c) The draft angle of the runners shall be (13 ± 3)°. The cavity shall have a draft angle not greater than 2°. d) The dimensions of the cavities shall be such that the dimensions of the test specimens produced conform to the requirements given in the relevant test standard. To allow for different degrees of mould shrinkage, the dimensions of the cavities shall be chosen so that they are between the nominal value and the upper limit of the dimensions specified for the specimen concerned. The main dimensions, in millimetres, of the cavities shall be as follows (see also Figure 1): length: 60 to 62; width: 60 to 62; depth: type D1 mould 2,0 to 2,1; type D2 mould 4,0 to 4,1. e) Ejector pins shall be located outside the test area of the specimen, i.e. in the area of the runner. -,-,- ISO 1268-11:2005(E) 4 © ISO 2005 All rights reserved f) The heating system for the mould plates shall be designed so that, under operating conditions, the difference in temperature between any point on the surface of a cavity and either plate is less than 3 °C. g) Interchangeable cavity plates and gate inserts are recommended to permit rapid changes in production from one type of test specimen to another. Such changes are facilitated by using shot capacities VS which are as similar as possible. h) Figure 1 shows the position of a pressure sensor P within the cavity, which is mandatory for the measurement of moulding shrinkage only (see ISO 2577). Such a sensor may be useful, however, in controlling the injection period with any ISO mould see ISO 1268-10:2005, Subclause 4.1.4, item k). The pressure sensor shall be flush with the cavity surface in order to avoid interference of the material flow. i) To ensure that cavity plates are interchangeable between different ISO moulds, it is important to note the constructional details given in ISO 1268-10:2005, Subclause 4.1.4, item l), in particular that the width of the mould plates may be affected by the minimum distance required between the connection points for the heating channels. j) To make it easer to check that all the specimens from a mould are identical, it is recommended that the individual cavities be marked, but outside the test area of the specimen. This can be done very simply by engraving suitable symbols on the heads of the ejector pins, thus avoiding any damage to the surface of the cavity plate. Another option is shown in Annex C. k) Surface imperfections can influence the results, especially those of mechanical tests. Therefore, where appropriate, the surfaces of the mould cavities shall be highly polished. The direction of polishing shall correspond to the direction in which the test specimen will be placed under load when it is tested. NOTE 1 The height and length of the gate strongly influence the process of curing of the plasticized material as it flows into the cavity, and hence the moulding shrinkage (see ISO 2577). The dimensions of the gate are therefore defined with tight tolerances. NOTE 2 Gates which are severely limited in height have a great influence on the orientation of the material within the cavity, even at large distances from the gate. The change in height at the gate has therefore been fixed at a value which facilitates subsequent measurement of the moulding shrinkage (see ISO 2577). NOTE 3 Separating the test specimens from the runner has to be done immediately after removal from the mould cavity. Otherwise, the plates will be irreversibly distorted due to the fact that the shrinkage of the runner and gate is different from that of the plate. NOTE 4 The distance lC between the lines along which the test specimens are cut from the runners is given by lC = 2(lG + lR + l*) (see Figure 2). Taking this distance as 80 mm gives the advantage that the same cutting device can be used to cut 80 mm × 10 mm × 4 mm bars from the central sections of multipurpose test specimens see ISO 1268-10:2005, Subclause 4.1.3 and Subclause 4.1.4, item l). 4.2 Injection-moulding machine For the reproducible preparation of test specimens capable of giving comparable results, only reciprocating- screw injection-moulding machines equipped with all the necessary devices for the control of the moulding conditions shall be used. The minimum mould-locking force FM for type D1 and type D2 ISO moulds is given by FM W 11 000 × pmax × 103, i.e. 880 kN for a maximum pressure on the material of 80 MPa. 5 Procedure 5.1 Conditioning of material Prior to moulding, condition the moulding compound as required in the relevant material standard or, in the absence of such information, as recommended by the manufacturer. -,-,- ISO 1268-11:2005(E) © ISO 2005 All rights reserved 5 Avoid exposing materials to an atmosphere at a temperature significantly below the temperature of the workshop to avoid condensation of moisture on to the material. 5.2 Injection moulding 5.2.1 Set the machine to the conditions specified in the relevant material standard or, in the absence of such information, agreed between the interested parties. 5.2.2 For many moulding compounds, the most suitable range for the injection velocity vI is (150 ± 50) mm/s when using a type D1 or D2 ISO mould. For a given value of the injection velocity vI, the injection time tI is inversely proportional to the number of c