1、BRITISH STANDARDBS ISO 14127:2008Carbon-fibre-reinforced composites Determination of the resin, fibre and void contentsICS 83.120g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51
2、g60g53g44g42g43g55g3g47g36g58BS ISO 14127:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 August 2008 BSI 2008ISBN 978 0 580 63104 7National forewordThis British Standard is the UK implementation of ISO 14127:2008.The UK participation
3、in its preparation was entrusted to Technical Committee PRI/42, Fibre reinforced thermosetting plastics and prepregs.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contra
4、ct. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations. Amendments/corrigenda issued since publicationDate CommentsReference numberISO 14127:2008(E)INTERNATIONAL STANDARD ISO14127First edition2008-03-15Carbon-fibre-reinf
5、orced composites Determination of the resin, fibre and void contents Composites renforcs de fibres de carbone Dtermination des teneurs en rsine, en fibre et en vide BS ISO 14127:2008ii iiiContents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Health and safety 2 4 Terms and definitions.
6、2 5 Principle. 2 6 Conditioning of test sample 3 7 Apparatus and reagents. 3 8 Test specimens . 4 9 Density measurements. 4 10 Procedures 5 11 Calculation and expression of results 7 12 Precision 9 13 Test report . 9 BS ISO 14127:2008iv Foreword ISO (the International Organization for Standardizatio
7、n) 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 rep
8、resented 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 a
9、re 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 Internatio
10、nal 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 14127 was pr
11、epared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 13, Composites and reinforcement fibres. BS ISO 14127:20081Carbon-fibre-reinforced composites Determination of the resin, fibre and void contents 1 Scope This International Standard specifies methods for calculating the resin, fibre
12、and void contents of a carbon-fibre-reinforced composite from the densities of the resin, the fibre and the composite and the mass of fibre in the composite (method A) and for calculating the fibre content from the thickness of the composite (method B). Method A specifies three different resin remov
13、al procedures for the determination of the mass of fibre in the composite (viz a combustion procedure, a procedure by digestion in nitric acid and a procedure by digestion in a mixture of sulfuric acid and hydrogen peroxide). The selection of the procedure to be used is made by considering the combu
14、stibility of the resin used in the composite, its ability to decompose and the type of resin concerned. It should be noted that method A is only of limited applicability when filled resins are present that could prevent complete dissolution and/or combustibility of the resin. Method B (thickness mea
15、surement method) is only applicable to composites moulded from prepregs of known fibre mass per unit area. 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, t
16、he latest edition of the referenced document (including any amendments) applies. ISO 291, Plastics Standard atmospheres for conditioning and testing ISO 472, Plastics Vocabulary ISO 1183-1, Plastics Methods for determining the density of non-cellular plastics Part 1: Immersion method, liquid pyknome
17、ter method and titration method ISO 1183-2, Plastics Methods for determining the density of non-cellular plastics Part 2: Density gradient column method ISO 1183-3, Plastics Methods for determining the density of non-cellular plastics Part 3: Gas pyknometer method ISO 5725-1, Accuracy (trueness and
18、precision) of measurement methods and results Part 1: General principles and definitions ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method ISO 5725-3, Accur
19、acy (trueness and precision) of measurement methods and results Part 3: Intermediate measures of the precision of a standard measurement method ISO 6353-2, Reagents for chemical analysis Part 2: Specifications First series ISO 10119, Carbon fibre Determination of density BS ISO 14127:20082 3 Health
20、and safety This International Standard limits itself to describing the determination of the resin, fibre and void contents of composites reinforced with carbon fibre. The conditions under which the test specimens, apparatus and reagents are handled shall comply with the national regulations in force
21、 in each country and the staff shall be informed of the hazards involved and appropriate precautions taken. 4 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 472 and the following apply. 4.1 fibre content by mass ratio of the mass of fibre in a composi
22、te to the total mass of the composite NOTE It is expressed as a percentage. 4.2 fibre content by volume ratio of the volume of fibre in a composite to the total volume of the composite NOTE It is expressed as a percentage. 4.3 void content ratio of the volume of the voids (hollow spaces) in a compos
23、ite to the total volume of the composite NOTE It is expressed as a percentage. 5 Principle 5.1 Method A (resin removal method) 5.1.1 Procedure A1: combustion procedure The mass of a test specimen is determined before and after combustion of the resin in the upper part of the reducing (non-oxygen) fl
24、ame of a Bunsen burner. NOTE The combustion procedure makes use of the relative ease of decomposition of resins, compared to carbon fibres, in inert gases. The procedure consists of heating a specimen of composite material with the reducing flame of a Bunsen burner so that only the resin is removed
25、by combustion. However, its application is limited to resins that decompose completely by combustion. Therefore, this procedure is not applicable to resins that are not completely combustible, such as epoxy novolac and brominated systems. There are also drawbacks such as the fact that the accuracy o
26、f the combustion procedure is slightly inferior to that of the nitric acid digestion procedure and the sulfuric acid/hydrogen peroxide digestion procedure. Nonetheless, it is useful as a rapid test procedure which can be carried out safely and simply. Because of the lack of reliability of the combus
27、tion procedure, its use shall be as agreed between the purchaser and supplier. 5.1.2 Procedure A2: nitric acid digestion procedure The mass of a test specimen is determined before and after digestion of the resin with concentrated nitric acid, which does not attack the carbon fibres excessively. NOT
28、E Both the nitric acid digestion procedure and the sulfuric acid/hydrogen peroxide digestion procedure make use of the fact that digestion of resins in a hot bath of nitric acid or sulfuric acid/hydrogen peroxide mixture is rapid compared BS ISO 14127:20083to carbon fibres (which resist digestion in
29、 such conditions). The procedure consists of soaking the composite in a hot bath of one of these reagents so that only the resins are removed by digestion. The nitric acid digestion procedure is applicable to all epoxy resins except acid anhydride curing substances. The sulfuric acid/hydrogen peroxi
30、de digestion procedure is applicable to all epoxy resins, phenolic resins and polyamide resins. 5.1.3 Procedure A3: digestion in a sulfuric acid/hydrogen peroxide mixture The mass of a test specimen is determined before and after digestion of the resin with an aqueous mixture of sulfuric acid and hy
31、drogen peroxide, provided that the carbon fibres are not attacked. See also the Note to 5.1.2. 5.2 Method B (thickness measurement method) The thickness of the composite is measured over the entire surface of the composite. Using known values of the mass per unit area and the density of the reinforc
32、ement, the fibre content of the composite can be calculated. 6 Conditioning of test sample A quantity of material sufficient to complete the tests is taken as the test sample and conditioned for a sufficient time to re-establish temperature equilibrium. This conditioning shall be carried out in one
33、of the standard atmospheres specifed in ISO 291. 7 Apparatus and reagents 7.1 General Normal laboratory equipment is required plus the following specific apparatus: 7.1.1 Desiccator, containing a suitable drying agent (e.g. silica gel). 7.1.2 Analytical balance, accurate to 0,1 mg. 7.1.3 Abrasive pa
34、per, with grain size finer than 180 grit. 7.2 Method A 7.2.1 Procedure A1 (combustion procedure) 7.2.1.1 Bunsen burner, compatible with the gas used. 7.2.1.2 Nichrome wire, about 0,2 mm in diameter. 7.2.2 Procedure A2 (nitric acid digestion procedure) 7.2.2.1 Borosilicate-glass vacuum filter. 7.2.2.
35、2 200 ml conical flask. 7.2.2.3 100 ml measuring cylinder. 7.2.2.4 Water reflux condenser, with a standard taper joint to fit the conical flask. 7.2.2.5 Air-circulation drying oven, capable of heating up to about 200 C. BS ISO 14127:20084 7.2.2.6 Acetone, as specified in ISO 6353-2. 7.2.2.7 Concentr
36、ated nitric acid, 62 % by mass. 7.2.3 Procedure A3 (digestion in a mixture of sulfuric acid and hydrogen peroxide) 7.2.3.1 Borosilicate-glass vacuum filter. 7.2.3.2 Borosilicate-glass beaker, minimum volume 200 ml. 7.2.3.3 100 ml measuring cylinder. 7.2.3.4 Air-circulation drying oven, capable of he
37、ating up to about 200 C. 7.2.3.5 Acetone, as specified in lSO 6353-2. 7.2.3.6 Concentrated sulfuric acid, 96 % by mass. 7.2.3.7 30 % to 35 % hydrogen peroxide solution. SAFETY PRECAUTIONS When handling nitric acid, sulfuric acid or hydrogen peroxide, care shall be taken to prevent accidents, as foll
38、ows. Wear rubber gloves, protective goggles, etc., in order to avoid direct contact of these reagents with the human body. If human skin does come into contact with one of these reagents, appropriate treatment shall be provided immediately. It is also necessary to ventilate the test area and/or room
39、. Boiling 65 % hydrogen peroxide can decompose explosively; do not therefore allow it to concentrate by distillation. Waste chemicals should be kept separate and disposed of in a suitable way. 7.3 Method B (thickness measurement method) 7.3.1 Ball micrometer or equivalent instrument, reading to an a
40、ccuracy of 0,01 mm, to measure the specimen thickness. 8 Test specimens 8.1 The mass of the test specimens shall be 0,2 g to 0,5 g. They shall be less than 4 mm in thickness and shall be 6 mm to 10 mm in length and width. 8.2 The locations from which the test specimens are taken shall be distributed
41、 randomly over the sample and be no nearer than 10 mm to any edge. 8.3 The edges of the test specimens shall be ground square and smoothed with abrasive paper. 8.4 At least three test specimens shall be taken unless otherwise specified by the party requesting the test. 9 Density measurements 9.1 Det
42、ermine the densities of the resin, the composite and the carbon fibre as follows. 9.2 Determine the density of the resin (r) in accordance with ISO 1183-1, ISO 1183-2 or ISO 1183-3. 9.3 Determine the density of the carbon fibre (f) in accordance with ISO 10119. 9.4 Determine the density of the compo
43、site (c) by the immersion method specified in ISO 1183-1. Use water as the immersion liquid. BS ISO 14127:200859.5 When measuring resin and composite densities by the immersion method, it is essential that a correction be made for the mass of the wire used to suspend the specimen. 10 Procedures 10.1
44、 General Measure the mass of the test specimen and that of the fibre by procedure A1 (combustion procedure), procedure A2 (nitric acid digestion procedure) or procedure A3 (digestion in sulfuric acid/hydrogen peroxide). When using method B, simply measure the thickness of the composite (see 10.3). 1
45、0.2 Method A 10.2.1 Procedure A1 (combustion procedure) 10.2.1.1 Weigh a test specimen to the nearest 0,1 mg (m). 10.2.1.2 Bind the specimen with nichrome wire as shown in Figure 1. Weigh the specimen, including the nichrome wire, to the nearest 0,1 mg (m1). Key 1 flame 2 reducing zone of flame 3 Bu
46、nsen burner 4 tweezers 5 nichrome wire 6 specimen reinforced with unidirectional carbon fibres 7 specimen reinforced with woven carbon fibre fabric Figure 1 Procedure A1 (combustion procedure) BS ISO 14127:20086 10.2.1.3 Light the Bunsen burner with the air shut off. Adjust the height of the flame t
47、o between 15 cm and 20 cm. Gradually increase the supply of air to bring the height of the reducing flame (blue flame) to about 2 cm. Using tweezers to hold the nichrome wire binding the specimen, introduce the specimen horizontally into the flame a little above the top of the reducing zone of the f
48、lame, but without at any time touching the reducing zone, as shown in Figure 1. 10.2.1.4 Within five to twenty seconds, most of the resin in the specimen will be burnt off, producing a red flame and black soot. Continue to heat the specimen until its bottom surface becomes red hot. Then invert it un
49、til the other surface becomes red hot. When all the resin has been burnt off, the red flame will disappear. Continue heating until this happens. The total heating time will normally be 3 min or less. 10.2.1.5 Remove the specimen from the flame and place it on a metal plate to cool to room temperature. If the specimen is not weighed at once, place the plate plus specimen in a desiccator. 10.2.1.6 Weigh the specimen, including the nichrome wire, to the nearest 0,1 mg (m2). 10.2.2 Procedure A2 (nitric acid digestion procedure) 10.2.2.1 Weigh a test
