ASTM D3530 D3530M-1997(2003) Standard Test Method for Volatiles Content of Composite Material Prepreg.pdf

1、Designation: D 3530/D 3530M 97 (Reapproved 2003)Standard Test Method forVolatiles Content of Composite Material Prepreg1This standard is issued under the fixed designation D 3530/D 3530M; the number immediately following the designation indicates theyear of original adoption or, in the case of revis

2、ion, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method co

3、vers the determination of the vola-tiles content, in weight percent of composite material prepregs.This standard focuses on composites with thermosetting resinsthat tend to lose a few percent of the matrix mass when heateddue to loss of both retained water and low molecular weightmatrix constituents

4、 that volatilize during heating.1.2 Use of this test method is limited to maximum tempera-ture of circulating air ovens (approximately 300C).1.3 Use of this test method is limited to temperatures belowwhich the matrix flows from the reinforcement.1.4 The values stated in SI units are to be regarded

5、asstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Spe

6、cific precau-tionary statements are given in Section 8.2. Referenced Documents2.1 ASTM Standards:2D 833 Terminology Relating to PlasticsD 3529/D 3529M Test Method for Matrix Solids Contentand Matrix Content of Composite PrepregD 3878 Terminology of Composite MaterialsE 177 Practice for Use of Terms

7、Precision and Bias inASTM MethodsE 1309 Guide for the Identification of Composite Materialsin Computerized Material Property Databases2.2 NFPA Standard:NFPA 86 Standard for Ovens and Furnaces33. Terminology3.1 DefinitionsTerminology D 3878 defines terms relatingto composite materials. Terminology D

8、883 defines termsrelating to plastics. Practice E 177 defines terms relating tostatistics. In the event of a conflict between terms, TerminologyD 3878 shall have precedence over other documents.3.1.1 prepreg, nthe admixture of fibrous reinforcementand polymeric matrix used to fabricate composite mat

9、erials. Itsform may be sheet, tape, or tow. See Terminology D 3878.3.2 Definitions of Terms Specific to This Standard:3.2.1 Volatiles Content, nthe amount of volatiles presentin a prepreg expressed as a weight percent.3.3 Symbols:3.3.1 Mithe initial mass of the sample.3.3.2 Mfthe mass of the sample

10、after oven exposure.3.3.3 Vcthe weight percent volatiles content.4. Summary of Test Method4.1 Specimens of prepreg are weighed and then exposed toelevated temperature, equal to the nominal cure or consolida-tion temperature of the material, in an air circulating oven toremove the volatiles. The expo

11、sed samples are reweighed andthe percent change in weight expressed as volatiles content.5. Significance and Use5.1 This test method is used to obtain the volatiles contentof composite material prepreg. Knowledge of the volatilescontent is useful in developing optimum manufacturing pro-cesses.5.2 Th

12、e volatiles content is determined after exposure to thenominal cure or consolidation temperature.6. Interferences6.1 AirflowThe amount of measured volatiles may beincreased or decreased by changing the velocity of airflow.Since airflow in most ovens is not linear in each part, avelometer should be u

13、sed to measure airflow where samplesare placed. Samples should be placed only in positions ofknown airflow so that results may be repeatable. Use of baffleshas been found to even airflow between samples.1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is th

14、e direct responsibility of Subcommittee D30.03 onConstituent/Precursor Properties.Current edition approved Oct. 1, 2003. Published October 2003. Originallyapproved in 1976. Last previous edition approved in 1997 as D 3530/D 3530M 97.2For referenced ASTM standards, visit the ASTM website, www.astm.or

15、g, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from National Fire Protection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02269-9101.1Copyright ASTM Internati

16、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Sample ExposureThe geometric shape and position-ing of the sample have an effect on the measured volatilescontent. Samples placed horizontally in a rack will not beexposed to the same amount of airflow as s

17、amples hungvertically. A ribbon wound in a 150 mm diameter hoop maygive slightly different results than the same ribbon wound in a50 mm diameter hoop. A thinner sample will be exposed tomore airflow at its surface than a thicker sample.6.3 Time of ExposureFor any given temperature, sampleplacement,

18、and airflow, the sample will lose volatiles at a setinitial rate, that decreases over time. After some time period,volatiles lost in the test will approach the true volatiles contentof the sample. If the time period is not sufficient to show a truevolatiles content of the material, the volatiles con

19、tent isrepresentative of only the condition of the test.6.4 Time of Ambient ExposureVolatiles content varies dueto prolonged exposure of temperatures exceeding prepreg glasstransition temperature or exposure to humidity. This change isassociated with matrix crosslinking and change in tack.7. Apparat

20、us7.1 Cutting BladeDie cutter that provides fixed specimenarea to within a tolerance of 0.5 % is recommended. Singleedge blade is acceptable.7.2 Cutting TemplateWhen a die cutter is not used, acutting template is required. The cutting template shall havegrooves within a tolerance of 0.4 mm parallel

21、true positionfrom center line. This allows a 2 % area error.7.3 Analytical BalanceThe analytical balance shall becapable of reading to within 60.1 mg.7.4 Circulating Air Oven, capable of tolerance within 63C.Removable baffles should be placed in the oven so that airflowis not directly aimed at the s

22、pecimen.7.5 Rack, that allows air circulation and from which hooksmay be suspended.7.6 Timer, capable of reading 20 6 1 min.7.7 Desiccator.8. Hazards8.1 Some materials contain flammable or toxic solvents aspart of the matrix. These materials could build up to dangerousconcentrations of vapor in the

23、oven. NFPA 86 providesguidelines on amount of flammable materials that may besafely placed in an oven.9. Test Specimens9.1 A minimum of three specimens shall be tested for eachsample.9.2 The specimen size shall be a minimum of 1600 mm2bymaterial thickness. Ribbon, braid, and fabric forms that do not

24、drip resin shall be suspended from the rack. Ribbon shall belooped in close proximity so that individual strands are notclumped together. Other forms may be placed horizontally onthe rack.10. Calibration and Standardization10.1 All measuring equipment shall have certified calibra-tions that are curr

25、ent at the time of use of the equipment. Thecalibration documentation shall be available for inspection.11. Conditioning11.1 Store carbon fiber-epoxy prepreg at low temperaturesas recommended by the manufacturer (typicallyapproximately 18C). Allow sealed packages of material towarm as recommended by

26、 manufacturer or controlling speci-fication before seal is opened to ensure that the material doesnot absorb moisture from the atmosphere.12. Procedure12.1 Weigh each of the three specimens on an analyticalbalance to 0.1 mg. Record the mass of each specimen as Mi.12.2 Coat any surfaces of the rack o

27、r clip that may contactthe specimen with a suitable release agent to prevent loss ofspecimen weight due to resin adherence.12.3 Place the samples on the rack or suspended from therack (braids, ribbons, and fabric) as quickly as possible, placethe rack into a preheated oven, and set at the nominal cu

28、re orconsolidation temperature as recommended by the manufac-turer or controlling specification. The specimens should beplaced so that the maximum surface area is exposed to thecirculating heat.12.4 Set the timer for 15 min.NOTE 1Other times may be used, but a timed study shall beperformed showing t

29、hat at least 90 % of the maximum volatiles content isobtained at the recommended time.12.5 Remove the specimens from the rack and place them ina desiccator.12.6 Remove the specimens from the desiccator after theyhave cooled to ambient (a minimum of 5 min). Weighspecimens within 1 min of removal from

30、 desiccator. Recordthis mass as Mf.13. Calculation13.1 Calculate the volatiles content Vc, weight percent, ofeach specimen as follows:Vc5Mi2 MfMi3 100 (1)where:Mi= initial weight of prepreg specimen, g, andMf= weight of specimen after removed from oven, g.14. Report14.1 Report the following informat

31、ion or references point-ing to other documents containing the information to themaximum extent applicable:14.1.1 Reporting of items that are beyond the control of agiven test laboratory, such as material details shall be theresponsibility of the requestor,14.1.2 Complete identification of the materi

32、al according toGuide E 1309 including fiber type, surface treatment, fibermanufacturer, resin system, resin manufacturer, prepreg manu-facturer, prepreg form, prepreg areal weight, and prepregmatrix content,14.1.3 The time and temperature to remove the volatiles,14.1.4 Specific ambient exposure cond

33、itions and time ateach condition, and14.1.5 The volatiles content for each of the three specimensexpressed as weight percent, the average volatiles content.D 3530/D 3530M 97 (2003)215. Precision and Bias15.1 PrecisionThe data required for the development of aprecision statement is not available for

34、this test method.Committee D30 is currently planning a round-robin test for thistest method in order to determine precision.15.2 BiasBias cannot be determined for this test methodas no acceptable reference standard exists.16. Keywords16.1 composite materials; prepreg; volatiles contentASTM Internati

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38、s, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 3530/D 3530M 97 (2003)3