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Page 1: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

Determination of the mechanical properties of a filamentwound glas fiber reinforced epoxy resinCitation for published version (APA):Huisman, M. R. S. (1994). Determination of the mechanical properties of a filament wound glas fiber reinforcedepoxy resin. (DCT rapporten; Vol. 1994.088). Eindhoven: Technische Universiteit Eindhoven.

Document status and date:Published: 01/01/1994

Document Version:Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers)

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Page 2: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

Determination of the Mechanical Properties of a Filament Wound

Glass Fiber Reinforced Epoxy Resin

stageverslag M.R.S. Huisman Rapport WEW 94.088

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Universität Kaiserslautern Erwin-Schrodinger-citralje D - 6750 Kaiserslautern

lxsTIT~-"F Ft iR Tel.: (0631) 2017-0 11 ER B u N D RKS -1 'O FEE F a : (0631) 2017-199

1. Lfd. Nr. 2. Datum 3. Abteilung 4TypderArbeit" 5. ArtderArbeit 6. Seiten

IVW 9 4 - 3 0 30-6-94 A USA experimentell 35 7. Titel und Untertitel Determination of the Mecanical Properties of a Filament Wound Glass Fiber Reinforced Epoxy Resin. Tension, Compression and Torsion Tests on Tubes and Flat Specimens.

8. Autor M.R.S. Huisman

9. Schlagworte Mechanische Eigenschaften, GFK, Zug, Druck, Torsion, Wickeln

IO. Kuïzfa§§uIpg Ziel dieser Arbeit ist die Bestimmung der mechanischen Materialeigenschaftein des gewickelten glasfaser verstärkten Epoxidharzes PlS§/LY§0§2. Das gleiche Material wurde während des Seminars "Analysis, Design, Manufacturing and Testing of a Composite Structural Component" als Werkstoff fik Kardanwellen verwendet. Als Proben wurden Rohre und Stäbe gewählt. Die Rohre wurden an einer Zug/DrucWTorsions- machine gepriift und die Stäbe an einer Zug/DrucWBiegungsmachine. Um eine bestimmte Reproduktionsfahigkeit bei der Probenherstellung zu gewiihrkisten, wurden die wichtigsten Fertigungsparameter während der Fertigung konstant gehalten. Die gemessene Werte der Materialeigenschaften wurden in einem P r o g r a m fur von Kardanwellen implementiert und mit einer Torsionsmessung an einer realen Kardanwelle überprii€t.

* TB: Technischer Bericht DA: Diplom-Arbeit SA: Studien-Arbeit

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Determination of the Material Properties of a Filament Wound Glass Fiber

Reinforced Epoxy Resin

Tension, Compression and Torsion Tests on Tubes and Flat Specimens.

Technical Report

Cand. Ir. .S. Huisman Eindhoven University of Technology

at the

Institut für Verbundwerkstoffe GmbH Design and Analysis Department

executive: Prof. Dr.-Ing. M. Maier supervisor: Dr.-Ing. N. Himmel

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ACKNOWLEDGEMENT

I wish to thank Dr. Ir. C. Oomens and Prof. Dr.-Ing. M. Maier who gave me the opportunity to do this work at the Institute for Composite Materials Ltd. Further thanks to Dr.-Ing. N. Himmel for the supervision and correction of this report and thanks to everyone who assisted me during my stay at the institute.

vivat, crescat, jloreat W W et EUT!

M a c Huisman

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TABLE OF CONTENTS

Table of contents

List of symbols and units

Chapter 1 :

Chapter 2:

Chapter 3 :

Chapter 4:

Chapter 5:

Chapter 6:

Introduction

Manufacturing and testing of the specimens

2.1 : Mamfac$xigg ~f the specimens 2.1.1: Winding, gelling and curing of tubes and flat specimens

2.2: Testing 2.2.1: Determination of the fiber volume fraction 2.2.2: Mechanical testing procedures

2.3: Results

2.4: Discussion

Design of a drive shaft program

3.1: The program CMAD

3.2: Calculation and measurement of a drive shaft

General considerations

References

Enclosures

5 5

8 8 9

12

17

19

19

19

21

22

23

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LIST OF SYMBOLS AND UNITS

inside diameter outside diameter width height length temperature room temperature resin bath temperature force of the roving on the core time measuring length measuring thickness thickness of the ends Young's modulus in fiber direction Young's modulus perpendicular to fiber direction Poisson's ratio strength in tension in fiber direction strength in tension perpendicular to fiber direction strength in compression in fiber direction strength in compression perpendicular to fiber direction shear modulus shear strength fiber volume fraction weight of matrix weight of specimen weight of vessel in which the specimen is put in weight of specimen before burning weight of specimen afier burning weight fraction of matrix weight fraction of fiber reinforcement density of the fiber reinforcement density of the matrix

mrrl

mm mm mm mm "C "C "C N h mm mm mm MPa MPa - MPa MPa MPa MPa MPa MPa %

g g g g g - - kg/m3 kg/m3

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The described work was carried out as part of an ERASMUS project at the Institute for Composite Materials (IVW) in Kaiserslautern, Germany. The purpose was to determine the mechanical properties of a glassfiber reinforced Epoxy resin (E-glass/LY5052/HY5052) which was subsequently used for the production of a drive shaft at the ERASM-ÜS intensive course "Manufacturing, Design and Testing of Composite Materials" in March

This report includes the manufacturing process of the specimens with a filament winding machine, the burning test for the determination of the fiber volume content, the mechanical testing procedures and the results of the measurements (chapter 2). The -aiUiïektiûm! !~;l,ir,zte properties were estered is sun, & IVW developed pregrstr, fer

the c~l"culattion of drive shafts to compare the Qive shaft, computed by the program, with torsional measurements on a real filament wound drive shaft.

10-17, 1994.

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2 MANUFACTURING AND TESTING OF THE SPECIMENS

2.1 MANUFACTURING OF THE SPECIMENS

For the determination of the mechanical properties two types of specimens were manufactured. Botin types of specimens, tubes and fiat specimens, were msde on a Boleriz- Schäfer seven-axis gantry precision filament winding machine, for specifications see enclosure 6.1. The flat specimens were wound as plates and afterwards cured in a autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties, it is important to control the manufacturing process in order to get a constant material quality. The materials used are E-glass Vetrotex p185 (300), E p x y resin A d d i t LY5052 and as hardener Araldit HY5052.

2.1.1 WINDING, GELLING AND C SPECIMENS

In order to avoid a cross-ply laminate while filament winding the tubes, the rotational direction of the core was reversed when reaching the hedgehog. The tubes -eight tubes on each core- were wound on a heatened core at 50°C which is the resin gelling temperature. After the winding (2 hours) the tubes stayed for two more hours on the filament winding machine while rotating at 50°C to assure that the resin is distributed continuously. During the filament winding process the following variables were measured or controlled: room temperature, core temperature, resin bath temperature, roving force and the amount of resin pressed on the roving, see tzbk 2.1 and enclosure 6.3.

Table 2.1: Process variables in the filament winding process, *: measured value, (adjusted value)

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After gelling the tubes where cured in a furnace at 80°C for a period of eight hours, see figure 2.1.

Figure 2.1: curing cycle, = tubes, _ _ _ _ _ - - flat specimens

The heating rate was 1°C per minute untill the curing temperature of 80°C was reached. The cooling rate was -1°C per minute untill a temperature of 50°C. Then the system was turned off and the curve followed a natural cooling path. In principal the manufacturing process for the flat specimens is the same. The two major differences are the temperature of the core and the curing in an autoclave instead of a furnace. The core, an aluminium plate, could not be heated during the winding process. Therefore it was heated to 50°C before winding and stayed after finishing the winding for four hours at 50°C instead of two hours as was the case for the tubes. An autoclave with vacuum bag and 7 bar pressure was used to put stress respectively pressure perpendicular to the surface of the core. By putting the plates in the autoclave the layers were bonded together. In order to avoid built-in stresses one edge was cut. Usually this results in washing out of the fibers. This problem can be solved by pressing and screwing aluminium plates on ledges, see figure 2.2. To establish a determined thickness of about 2.2 mm these ledges have a defined thickness of 2.1 mm (the protection sheets have a thickness of about 0.1 mm).

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b \ e

C

/- d

a

Figure 2.2: Production of a flat specimen laminate via filament winding, a: cutting through of the fibers, b: screws to tighten the plate(s) e, c: ledge to establish the wanted thickness, d: ledge to prevent bending of the aluminium plate(s), e: aluminium plate, w*l*d=300*700*10 mm.

The disadvantage of this method is a maximum fiber volume fraction which is about 60%. To get a fiber volume fraction of about 65% one could increase the pressure in the autoclave. Usually this leads to stress induced cracks but with one edge cut these stresses do not appear. Another way to increase the fiber volume fraction is by drawing off the polymer during the winding process. The disadvantage of this is the extra working time.

2.2 TESTING

Before the testing started the specimens were put in a control climate of 20°C and about 50 % relative moisture content, a norm climate. The specimens stayed in this room for at least one week to adapt to this norm climate.

INATION OF THE FIB

Determination of the fiber volume fraction is based on the difference in heat properties between fiber and matrix. The gIass fiber has excellent resistance against heat compared to

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the weak resistance of the organic Epoxy resin. Therefore the burning test is a suitable test for the determination of the fiber vohme fraction. By putting the specimen in a furnace at 600°C the matrix was burned off. Determining the weight of the specimen before burning, after burning and the weight of the burning vesse1,see enclosure 6.4, the weight fraction of the fiber reinforcement wym can be calculated as follows:

I I w,=l -w, (with the assumption of xo void content)

with q,, = w-eight of matïix ms = weight of sFecixnen

m, ms 1

ms2 w,' w,'

= weight of vessel in which the specimen is put in = weight of specimen before burning = weight of specimen after burning = weight fraction of matrix = weight fraction of fiber reinforcement

With the densities of the matrix and fiber and the fiber weight fraction the fiber volume fraction can be found by using the expression

with Vf = volume fraction of fiber reinforcement

Pf P m

= density of the fiber = density of the matrix

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O2t7 O20 ‘129

2.2.2 TESTING PROCEDURES

Puck [3] Suter

The tubes were tested in tension, compression and torsion, the flat specimens in tension and compression. The conditions for the tensile tests correspond to DIN EN 61, for the compression tests to DIN 65380. The tests on the flat specimens were performed on a Zwick 1485 universal testing machine, see enclosure 6.5. In case of the tensile test the specimens were of type 3 according to DIN EN61 [i], see also hbie 3.2. The precise determination of the properties can be seen in enclosure 6.6. The geometry of the compression specimens was adjusted to fit into a Celanese compression tool. To determine the specimen geometry a micrometer measuring device was used [1,2]. Because no standardized method was available for the testing of glassfiber reinforced epoxy resin in tubular shape, the testing conditions were the same as described by Puck [3j. The specimens were tested on a Suter biaxial testhg machine (ZDT), see enclosure 6.7. The testing machine applied a force or torque which represented a stress of 1 N/(mm2s) in the specimens. An overview of property against testing standard or reference and testing machine can be seen in table 2.2.

Table 2.2: Overview of property against testing standard and testing machine.

To be sure that no systematic measurement failure appeared the ZDT-machine was calibrated before the real testing started. This was done by testing an aluminium AlMgSiO.5 F22 tube with the same geometry as the glassfiber reinforced specimens to be tested, see enclosure 6.8. Comparing the results of the tests on the aluminium specimens with the given properties leads to the conclusion that the measuring devices and the testing machine worked well.

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Table 2.3: Average geometry of the specimens

The strain measurement was done using strain gages. On the flat specimens 3 mm strain gages’ were used, on the tubes the strain was measured with 6 mm strain gages”. In measuring the strain on tensile specimens one-fowth Wheatstone bridges were used. Unfortunately the software of the testing machine supported only half bridges and full bridges. In this case a half bridge was simulated by soldering a resistance of 120 R instead of a strain gage, see figure 2.3.

$ type: EA-06-060LZ-120, 3 mm, 120 R, Measurements Group Inc. $$ type: CEA-06-240UZ-120, 6 mm, 120 R, Measurements Group Inc.

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11 I

Figure 2.3: Circuit diagram of a: a simulated half bridge of Wheatstone, b: half bridge of Wheatstone

This solution results in a resistance difference which is just half as big as the real difference and therefore the calculated strain just half as big as the real strain. Therefore it is necessary to multiply the measured value by a factor of two. To measure the strain in torsion tests two strain gages were soldered in a half bridge [4], see figure 2.3.

2.3 SULTS

The various tests result in the mechanical properties listed in table 4.1. This table consists of the mean value, the standard deviation s, the student-t 95 % confidence interval and the fiber volume fraction of the specimens, see table 2.4. An overview of the single results can be seen in enclosure 6.9. The volume fraction of fiber reinforcement for the tubes and flat specimens is not the same. Later this will be corrected.

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Mechanical properties of E-glass/LY5052-HY5052 I unit propew mean value standard

deviation intewal

1442 I 44617 f 1206 (2.7 %) MPa

1205

1373

30277 0 O09 (2.7 %)

16308 k 1441 (8.8 %) MPa E2t 16308

I - * MPa

I (312 I 6415 6415 k 98.2 (1.5 %)

0.013 0.42 10.016 (3.8 %)

I 1097 t: 28.8 (2.6 oh) I 27.43

MPa

- I v12 I 0.42

I 1097 86.28 I 1097 & 90.56 (8.3 %) MPa

I <32t I 40.9 MPa 1.16 I 40.93 f 1.07 (2.6 %)

I 0 2 c * I MPa

MPa 0.26 59.96 f 0.24 (0.4 %)

Table 2.4: Mechanical properties of E-glassBLY5052-HY5052 *: These properties could not be measured, see page 15.

In case of the tensile test on the flat specimens (DIN EN61), the tensile strength was calculated from the maximum force and the Young's modulus from the stress difference between 0.1 % and 0.75 % strain. This was done because the linear variable differential transducer to measure displacement is very sensitive and at 1 % strain the transducer was replaced by the cross head displacement of the testing machine to prevent it fiom being damaged by the cracking of the fibers. A typical result of this kind of tests can be seen in figure 2.4.

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150C

1200

900

600

300

O I t I I I 1 I I

O 1 .o 2.0 3.0 4.0 5.0 6.0

strain [Y’]

Figure 2.4: Typicai resuit o f a tensile test.

The maximum strain is not the real strain because the cross head diplacement includes the real strain, the strain of the clamps and the strain in the frame of the machine. This results in a strain larger than the real strain in the material and so in a lower apparent Young’s modulus for strains above 1%. To get mechanical and statistical reliable results at least 6 good tests are necessary [i]. From 8 tests 2 specimens were pulled out of the tabs which left 6 good tests. The strength values of the two specimens which were pulled out of the tabs could not be used while there Young’s modulus could be calculated. The specimens (DIN 65380) were tested on the Zwick universal testing machine 1485 using a Celanese compression test fixture. Here strain gages were adhered on six specimens to demonstrate if buckling occurred. The Young’s modulus calculated with these strain

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gages and the Young's modulus calculated with the cross head displacement were about the same. Due to the greater number of specimens available without strain gages the Young's modulus was calculated with the cross head dispacement.

The Celanese compression test fixture can lead to complications as can be seen in figure 2.5.

m a a S

u) u)

.-

L 3i

1400

1200

1 O00

800

600

400

200

O O 1 2 3 4 5

Strain in %

Figure 2.5: Typical result of a compression test

Up to a strain of 1 % there is a stress plateau of about 40 I"a where only the fixture is compressed a d not the specimen. This plateau is caused by the internal friction of the compression fixture. To prevent such a plateau the pre-compression force should be higher or the construction should be polished. To determine the right compression strength it was necessary to decrease the maximum stress value with the magnitude ofthe plateau stress. On the ZDT testing machine the tubes were tested in tension, compression and torsion. Typical results for these tests can be seen in the figures 2.6 and 2.7.

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50

40

30

20

10

O 0 , o

15

Figure 2.6: Typical result for a tensile test perpendicular to fiber direction.

and GI, were calculated by determing the stress difference at strains of 0.02 and 0.1 %. For both types of tests this corresponds to the linear part of the respective stress- strain curves. The mechanical properties and B , ~ could not be measured due to slipping of the clamps caused by relative large strains in the reinforcement in radial direction. To avoid this slipping one could try to increase the transverse tab stiffness, i.g. by winding the tab reinforcement out of carbon fibers. An estimation of these properties is for the Young's modulus E,, = 17687 ma, the same value as in tension, and for the compression strength perpendicular to the fiber direction

= 120 TvlPa. This valine is given by the manufacturer CIBA GEIGY, see table 2.5.

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n E E

.r a3 3

O 4-

1200

1 O00

800

600

400

200

O O 1 2

strain [%]

Figure 2.7: Typical result for a torsion test

To compare the results of the tubes with the flat specimens at different fiber volume fraction, respectively 62% and 54%, one can scale the properties of the flat specimens to values which correspond to 62% Îiber volume fraction. The value 62% is dose to &ie wanted value of 65% (of a drive shaft), so the properties of the tubes need not to be scaled.

Table 2.5: Scaled mechanical properties (from V, = 54% to V, = 62%) of E-glassLY 5 05 2/HY 5 052

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The mechanical properties can only be scaled in the case of fiber dominated behaviour, i.e. in tension in fiber direction. The scaling is done by using the linear formula: ”new property = old property * (new fiber volume fraction / old fiber volume fraction). In other cases, i.e. mechanical properties due to compression, transverse tension or shear, scaling leads to less reliable or unreliable results. The results can be seen in table 2.5.

2.4 DISCUSSION

When looking at table 2.4 one can see that the specimens were manufactured with constant quality. This can be seen from the small standard deviation of about 3 %. In case of the Young’s modulus in tension perpendicular to fiber direction EZt and the strength in compression in fiber direction the relative large standard deviation is caused by the testing procedure. One should bear in mind that there is a difference in fiber volume fraction of the tubular specimens and flat specimens and the materials in table 2.5 while interpreting the properties. The tension modulus perpendicular to fiber direction E,, is rather high compared to values in table 2.5 what could be caused by the difference in resin type and curing cycle. This could also be the cause for the rather high shear modulus GI2. The difference between the here measured Poisson’s ratio and in the literature measured Poisson’s ratio could be caused by the way of measuring the strains. The strain in fiber direction was measured with a linear variable differential transducer and the strain perpendicular to the fiber direction was measured with strain gages, both with different amplifiers. The difference between these two methods could cause the relatively high value of the Poisson’s ratio. The other values are of the same order of magnitude as the values measured elsewere, see table 2.5.

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1s

institute IVW

PI S5/ LY5052- HY5052

E-glass/ Gevetex E-glass/ E-glass/

LY556- p103/ EPOXY EPOXY HT972 CY232

LY5052-

43400 1 I 48700 I 54000

I - I 36000

E2t [MPa] I 16732 12500' 8270 1261 1 15410

I I - I I

GI2[MPa] 1 6415

1 0.27 1 (3;. 1 0.27 1 1600 1300 1400

1600 1300

clt [ m a ] 1 1260

clc [MPa] I 1260

29-50 o,, [ m a ] I 40.9

119-129

57-69

60

p [kg/m3] 2288

curing 1 SW80"C 1 5h/50°C

Table 2.5: Comparison of different glass fiber reinforced epoxy resins # average value () estimation

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3 DESIGN OF A DRIVE SHAFT PROGRAM

3.1 THE PROGRAM CMAD

The ANSI-C program ’CMAD’ -Cornposit Material Analysis of Drive shafts- provides a plane stress laminated plate analysis based on the classical theory of laminate [ó]. Giving UD-ply properties, laminate structure and applied torque, the program computes stiffness and resistance of a drive shaft. The calculation includes temperature and moisture effects and a Tsai-Wu failure criterion. Moreover simplified equations for the critical buckling stress of cylindrical shells have been implemented. The following assumptions should be taken into account: * 1’ 11neit~ elastic xateïia! behavimï, * identical tensiorJcem2ressiori Young’s ~ ~ d d u s , * interlaminar shear stresses and normal stresses do not appear, * ratio: (middle face radius)/(wall thickness) 2 10, * shear centre and radius correspond together, * limitation to pipes whose lengths are multiple of their diameters.

A flow diagram of the program can be seen in enclosure 6.11.

3.2 CALCULATION AND RIEASU MENT O F A D SHAFT

l o veri& both the program and the measurements cia the UD-lminate specimens the properties of the UD-laminate were entered in the program CMAD. The by the program computed properties of a drive shaft were then compared with a torsional measurement on a real filament wound drive shaft. A diagram of this measurement can be seen in enclosure 6.10. In table 3.1 torque M,, shear modulus GI2, shear stress I: and twist angle $I computed by the program CMAD are compared with the values measured during the Erasmus intensive course.

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ProperS. Mt [NmI Gxy [Wal

CMAD 2350 9610

ERASMUS 2350 9129

-T [ W a l 0 ["I 79.1 16.4

79.1 16.6

Table 3.1 : Comparison of computed and measured properties of a drive shaft

The calculated values agree well with the measured values with a difference at the most 5 %. The calculated shear stress should be the same as the measured one because the same formulas were used. The program predicted failure of the drive shaft by the Tsai-Wu failure criterion at Mt=2350 Nm while the real failure load was at Mt=4000 Nm. This could be caused by the limitations of the Tsai-Wu failure criterion (no interlaminar shear stresses and normal stresses) which results in a predicted failure load which is lower than the real (torsionai) ioaci.

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4 GENERAL CONSIDERATIOMS

It is important to realize that the mechanical properties of a composite material in general depend on i.g. the manufacturing procedure, the testing procedure and the place of manufacturing and testing. To manufacture the specimens in a reproducable way one needs a special sensitivity and constant process. This means that the properties of the material depend strongly on the person who manufacture it. Therefore one has to proceed with caution when using these measured values. This can be seen in table 2.5 where values of material properties measured elsewere are shown. Not knowing the manufacturing procedure, the curing cycle or even the exact composite system of UD-composites it is hard to compare these values with the values which I measured at the institute.

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5 REFERENCES

[i] DIN EN 61

22

~.

Glasfaserverstärkte Kunstoffe, Zugversuch

[2] DIN 65380 Faserverstiirkte K-msfoffe, Prüfimg von unidirektionalen Laminaten und Gewebe-Laminaten, Druckversuch

[3] A. Puck, H. Schürmann, Die ZuglDruck-Torsionspdïg an rohrförmigen Probekö rpern, 1 8. Öffentliche Jahrestagung der Arbeitsgemeinschaft Verstärkte Kunstoffe e.v., Freudenstadt, 1982.

[4] K. Hoffmann, Eine Einfiihrung in die Technik des Messens mit DehnungmeBstreifen, Hottinger Baldwin Messtechnik GmbH, Darmstadt, 1987.

[SI LTH Faserverbund-Leichtbau, Statische Werkstoffkennwerte von unidirektionalen faserverstärkten Epoxidharzen, MBE3 GmbH, VB 22 200- 1 O

[6] D. Hull, An introduction to composite materials, Cambridge University Press, 1985

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6 ENCLQSURES

6.1 FILAMENT WINDING MACHINE

Manufacturer: Bolenz & Schäfer Type of machine:

Technical data:

seven axis gantry precision filament winding machine

max. diameter of mandrel: 1500 mm inax. carriage stroke: 4000 zxx mzx cmriage speed: 60 mímin max rotational speed: 200 rpm number of axis: 7 number of spindles: 3

6.2 AUTOCLAVE

Manufacturer: Type of machine: autoclave

Scholz GmbH & Co KG

Technical data:

max. pressure: 25 bar max. working temperature: 500 "C wall temperature: 250 "C vacuum capacity: 98% contents: 2350 liter

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6.3 WESINBATH

b force

from spool

Figure 7.3.1: roving course; from the spool through the resin bath to the mandrel. a: glider to remove excess resin from the wheel b: resin pressed on the roving c: wheel which can be pressed on the big wheel with adjustable force.

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25

6.4 WEIGHT DIFFERENCES IN O ER TO DETEIRMINE THE FIBER VOLUME FRACTION

-- Specimen No. Specimen type Spec. weight Vessel+Spec. 1 Vessel+Spec. 2 --

[SI [SI [SI

A I tube

I B

8.316 3 1.79 29.59 --

Weight frac.

[%I 0.2059 I 0.7941

62 0.2049

0.2057 0.7943 62

O. 1966 0.8034 63

0.795 1

0.2650 0.7350 54

0.2692 0.7308 53

0.2665 0.7335 54

Table 3: Weight differences for the determination of the fiber volume fraction.

Page 30: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

6.5 TENSION, COMPRESSION AND BENDING TEST MACWINE

Manufacturer: Zwick Type of machine: universal testing machine, Zwick 1485

Technical data:

Statical capacity: 250 kN Maximum of displacement: 1500 m speed: 0.025-2000 &min temperature: -70 till +250°C different clamps: e.g. hydradie cimqx Di SPI. Iiieasüïenefit : ?y stmk gzges, indwtive meusurement w-d

traverse measurement

Page 31: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

27

6.6 DETERMINATION OF §INGLE PROPERTIES

A U = - AF W a l A

Figure 6.6.1: Young’s modulus in fiber direction in tension El,

Figure 6 . 6 2 Young’s modulus in fiber direction in compression E,,

c--Ic 4 Ea f, X l

W a l AF AU = - A

A e = 2 * Aea [%I

EZt = - A u * loo al A E

Figure 6.6.3: Young’s modulus perpendicular to fiber direction in tension EZt

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28

, ,

F, = 1800 till 2000 [NI

Figure 6.6.4: Poisson’s ratio uI2

Figure 6.6.5: Shear modulus 6 1 2

Page 33: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

29

6.7 TENSION, CQMPRESSION AND TORSION TEST MACHINE

Manufacturer: Suter, Base1 Type of machine: multiple purpose machine ZDT 16;

hydraulic

Techincal data:

Statical capacity: 150 kN max. torsional moment: 3400 Nm

Measuring box: +2"/,, Measuring range: Width: 850 mm

50, 100, 150, 200, 1500, 3400 kN

Depth: 900 mm height: 2820 mm

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30

6.8 MEASUREMENT ON ALUMINIUM

Figure 6.8.1: Determination of the Young's modulus of aluminium AlMgSiO.5 F22.

Figure 6.8.2: Determination of the shear modulus of aluminium AlMgSiO.5 F22.

Page 35: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

31

6.9 RESULTS OF THE TESTS

*: slipping of the clamps **: bad sectors on floppy disk

Page 36: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

32

~ ~~ ~

1

2

3

987.9 28979

1131.3 * 29792

1144.8 30743

*: tab cracking, shear failure or buckling **: stress plateau within the calculation of the Young’s modulus

Page 37: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

33

specimen 0 2 t cMl+31 E2t W a l 1

2

3

39.97 15484

42.00 17555

42.50 17550

4 41.46

5 39.34

*: no strain gage

15370

- *

6335 - ** 8

6

7

*: no strain gage **: slipping of the clamps

41.11 17640

40.11 16789

Page 38: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

34

6.10 TORSIONAL TEST ON A DRIVE SHAFT __ __

: i t

Page 39: Determination of the mechanical properties of a filament ... · autoclave, see enclosure 6.2. Considering the purpose of the manufacturing, determination of the mechanical properties,

==il

1 I I I l

\

I-

4-

-i -

b

E


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