Properties of Two Carbon Composite Materials Using LTM25 Epoxy Resin

Transcription

1 NASA Tehnial Memorandum Properies of Two Carbon Composie Maerials Using LTM25 Epoxy Resin Juan R. Cruz Langley Researh Cener, Hampon, Virginia C. H. Shah and A. S. Posyn Norhrop Grumman Corporaion, El Segundo, California November 1996 Naional Aeronauis and Spae Adminisraion Langley Researh Cener Hampon, Virginia

2 Summary In his repor, he properies of wo arbon-epoxy prepreg maerials are presened. The epoxy resin used in hese wo maerials an yield lower manufauring oss due o is low iniial ure emperaure, and he apabiliy of being ured using vauum pressure only. The wo maerials seleed for his sudy are MR50/LTM25, and CFS003/LTM25 wih Amoo T300 fiber; boh prepregs are manufaured by The Advaned Composies Group. MR50/LTM25 is a unidireional prepreg ape using Misubishi MR50 arbon fiber impregnaed wih LTM25 epoxy resin. CFS003/LTM25 is a 2 by 2 will fabri using Amoo T300 fiber and impregnaed wih LTM25 epoxy resin. Among he properies presened in his repor are srengh, siffness, bol bearing, and damage olerane. Many of hese properies were obained a hree environmenal ondiions: old emperaure/dry (CTD), room emperaure/dry (RTD), and elevaed emperaure/we (ETW). A few properies were obained a room emperaure/we (RTW) and elevaed emperaure/dry (ETD) ondiions. The old and elevaed emperaures used for esing were -125 F and 180 F, respeively. In addiion, several properies relaed o proessing are presened. Symbols E 2 E 2 F p br F u br F y br F u ai u F 2 u F u oh F u oh su 2 longiudinal modulus, ompression ransverse modulus, ompression longiudinal modulus, ension ransverse modulus, ension bol bearing proporional limi sress bol bearing ulimae sress bol bearing yield sress ompression-afer-impa ulimae sress longiudinal ulimae sress, ompression ransverse ulimae sress, ompression open-hole ompression ulimae sress open-hole ension ulimae sress in-plane shear ulimae sress The use of rademarks or names of manufaurers in his repor is for aurae reporing and does no onsiue an offiial endorsemen, eiher expressed or implied, of suh produs or manufaurers by he Naional Aeronauis and Spae Adminisraion.

3 u F 2 u s G 12 M g T g T g dry T g we nom V f α 1 α 2 su γ 12 ε u ai ε 1 u ε 2 u ε 1 u ε 2 u ν 12 ν 12 ν 21 ν 21 ρ Supersrips br ai u dry oh oh s su u we longiudinal ulimae sress, ension ransverse ulimae sress, ension in-plane shear modulus moisure gain from he dry o he we ondiion glass ransiion emperaure glass ransiion emperaure, dry glass ransiion emperaure, we nominal ply hikness fiber volume fraion longiudinal oeffiien of hermal expansion a room emperaure ransverse oeffiien of hermal expansion a room emperaure in-plane ulimae srain ompression-afer-impa ulimae srain longiudinal ulimae srain, ompression ransverse ulimae srain, ompression longiudinal ulimae srain, ension ransverse ulimae srain, ension major Poisson's raio, ompression major Poisson's raio, ension minor Poisson's raio, ompression minor Poisson's raio, ension maerial densiy bol bearing ompression ompression-afer-impa ompression ulimae dry ondiion open-hole ompression open-hole ension shear shear ulimae ension ensile ulimae we ondiion 2

4 Subsrips f fiber g glass ransiion nom nominal 1 longiudinal 12 shear 2 ransverse Aronyms CAI CTD ETD ETW OHC OHT RTD RTW ompression-afer-impa old emperaure/dry elevaed emperaure/dry elevaed emperaure/we open-hole ompression open-hole ension room emperaure/dry room emperaure/we 1.0 Inroduion New resin sysems are being inrodued whih offer he possibiliy of reduing he manufauring oss of omposie maerials. These resin sysems an be ured a relaively low emperaures (ypially less han 200 F), followed by a pos-ure a a higher emperaure. This pos-ure inreases he omposie's glass ransiion emperaure, T g. If he omposie par is properly suppored, he pos-ure proedure an ake plae afer he omposie par has been removed from he ool. Suh resin sysems an lower manufauring oss by reduing demands on he emperaure apabiliy of he ooling; if he omposie par is o undergo a free-sanding pos-ure, he ooling does no have o wihsand he pos-ure emperaure, only he lower iniial ure emperaure. Tools for lower emperaure appliaions are ypially less expensive. Besides lowering ooling oss, a resin sysem wih hese haraerisis However, a free-sanding pos-ure is no neessary. If he ooling is apable of wihsanding he pos-ure emperaure, i is possible o pos-ure he omposie while sill in he ool. 3

5 an minimize problems relaed o mismahed oeffiiens of hermal expansion beween he ooling and he omposie par. Sine he ool and he omposie par only need o be in ona during he iniial lower-emperaure ure, he dimensional differene beween he ool and he par is minimized. For some appliaions, he maerial properies obained from he iniial ure, wihou he subsequen pos-ure, are suffiien. In addiion, many of hese maerials an be ured under vauum pressure only, eliminaing he need for an auolave, and furher reduing manufauring oss. There is lile informaion on he properies of omposies ha use hese new resin sysems. In referene 1, he properies of omposies using some of hese resins wih fiberglass reinforemens are invesigaed. However, no daa is presened for omposies using arbon fibers. In many appliaions arbon fibers are a neessiy due o he performane requiremens of he airraf. In his repor, he properies of wo arbon-epoxy prepregs using one of hese new epoxy resins, are presened. The wo maerials seleed for his sudy are MR50/LTM25, and CFS003/LTM25 wih Amoo T300 fiber; boh prepregs are manufaured by The Advaned Composies Group. MR50/LTM25 is a unidireional prepreg ape using Misubishi MR50 arbon fiber impregnaed wih LTM25 epoxy resin. CFS003/LTM25 is a 2 by 2 will fabri using Amoo T300 fiber and impregnaed wih LTM25 epoxy resin. The LTM25 resin an use iniial ure emperaures from 125 o 210 F. Iniial ure ime-emperaure ombinaions range from 12 hours a 125 F o 0.35 hours a 210 F. A wo hour pos-ure a 250 F is reommended o obain he bes properies. Curing pressure may be applied hrough auolave, vauum bag, or press molding. These prepregs were provided as ne-resin sysems; no bleeding during uring was required or reommended. The properies obained for hese wo maerials are lised in Tables 1, 2, and 3. Many of hese properies were obained a hree environmenal ondiions: old emperaure/dry (CTD), room emperaure/dry (RTD), and elevaed emperaure/we (ETW). A few properies were obained a room emperaure/we (RTW) and elevaed emperaure/dry (ETD) ondiions. The old and elevaed emperaures used for esing were -125 F and 180 F, respeively. (The old emperaure of -125 F was deermined by he requiremens of very high aliude airraf.) In addiion, several properies relaed o proessing are presened. All he omposie laminae manufauring was performed a Norhrop Grumman Corporaion. Speimen manufauring and esing was performed a Norhrop Grumman 4

6 Corp. and NASA Langley Researh Cener (LaRC). All he work performed a Norhrop Grumman Corp. was done under NASA onra NAS The daa presened in his repor is a summary of he resuls presened in referenes 2 and 3 (NASA Conraor Repors prepared by Norhrop Grumman Corp.), and addiional resuls from ess performed a NASA Langley Researh Cener. More deails on he esing and experimenal resuls an be found in referenes 2 and 3. The purpose of his repor is o summarize all he available resuls under one over. This work was sponsored by NASA's Environmenal Researh Airraf and Sensor Tehnology (ERAST) program. Readers are advised ha he resuls presened in his repor were obained from a limied number of ess and are inended o be used for maerial evaluaion purposes. These resuls mus no be onsidered o be maerial allowable values. 2.0 Manufauring All laminaes used in his sudy were manufaured by Norhrop Grumman Corporaion using he following proedure: Debulking 1) Debulk he layup afer every fourh layer under vauum of no less han 25 inhes of merury for 15 minues. Curing 1) Apply vauum of no less han 25 inhes of merury. 2) Inrease emperaure a he rae of 1 F/minue. 3) Hold emperaure a 150 F for 9.5 hours. 4) Cool laminae under vauum a a rae of 2 F/minue. 5) Release vauum. Pos-uring 1) Inrease emperaure a he rae of 2 F/minue. 2) Hold emperaure a 250 F for 2 hours. 3) Cool laminae a a rae of 6 F/minue unil emperaure has been lowered o a leas 140 F. 5

7 The laminae bagging layou used is shown in Figure 1. Sine he prepreg maerials used were ne-resin sysems, bleeding of he laminaes during ure was avoided. The personnel performing he manufauring noed ha hese prepregs exhibied unusually aggressive ak. Leaving he prepreg maerials a room emperaure for 24 hours redued he ak, and made he layup proess easier. Addiional laminaes of boh prepregs were manufaured solely o assess an alernae debulking proedure (he uring and pos-uring proedures remained as defined above). In his alernae debulking proedure, he layup was debulked every 24 layers under vauum of no less han 25 inhes of merury for one hour. No signifian differenes in he ulrasoni inspeion resuls or he void volume onen were found beween laminaes manufaured by he wo debulking proedures. 3.0 Inspeion All laminaes were ulrasonially inspeed by Norhrop Grumman Corporaion. This inspeion revealed signifian amouns of porosiy in laminaes manufaured from boh prepregs. The perenage void volume for all laminaes was deermined by he aid digesion mehod. For he MR50/LTM25 laminaes, he average void volume was 2.18 peren, wih minimum and maximum values of 1.42 and 3.85 peren, respeively. For he CFS003/LTM25 laminaes, he average void volume was 1.45 peren, wih minimum and maximum values of 1.21 and 1.82 peren, respeively. These relaively high values of void volume should be onsidered when inerpreing he resuls presened in his repor. A porion of one of he wo bahes of MR50/LTM25 prepreg had a 2-4 inh wide imperfeion along he middle of he prepreg ape. This imperfeion seemed o be aused by a hange in he fiber or resin onenraion. This peuliariy in he maerial was visible in he ulrasoni inspeion of he laminaes. 4.0 Speimen Condiioning Speimen ondiioning was performed boh a Norhrop Grumman Corp. and NASA LaRC. Two slighly differen ondiioning proedures were used depending on where ondiioning ook plae. Boh proedures are desribed below. Mehanial and bol bearing prop- 6

8 eries ess were performed on speimens using he Norhrop Grumman Corp. ondiioning proedure. Open-hole ompression (OHC), open-hole ension (OHT), and ompression-afer-impa (CAI) ess were performed on speimens using he NASA LaRC ondiioning proedure. Norhrop Grumman Corp. Condiioning Proedure All es speimens were dried in a vauum oven for 5 days a 160 F. Afer drying, speimens o be esed in he CTD and RTD ondiions were sored a 0 F in moisure-proof bags unil esing was performed. Speimens o be esed in he ETW ondiion were moisure ondiioned in a humidiy hamber a 160 F and 98% relaive humidiy unil he moisure onen remained approximaely unhanged. For all ess exep bol bearing, he moisure onen was approximaely 0.83% and 1.05% for MR50/LTM25 and CFS003/LTM25, respeively. For bol bearing ess, he moisure onen was 1.19% and 1.20% for MR50/LTM25 and CFS003/LTM25, respeively. Afer moisure ondiioning, speimens o be esed in he ETW ondiion were sored a 0 F in moisure-proof bags unil esing was performed. NASA LaRC Condiioning Proedure Properies of speimens in he CTD, ETD, and RTD ondiions were obained by esing hem in he as-ured ondiion. Speimens o be esed in he RTW and ETW ondiions were moisure ondiioned by full immersion in waer a 160 F for 123 days. The moisure onen was 1.72% and 2.03% for MR50/LTM25 and CFS003/LTM25, respeively. These moisure onen numbers assume ha he as-ured ondiion had 0% moisure onen. Speimens ha were moisure ondiioned were esed wihin 72 hours of removal from he ondiioning hamber. 5.0 Tesing The es proedures used o deermine he mehanial properies are lised in Table 4. The es proedures used o deermine he sruural properies are lised in Table 5. For boh he mehanial and sruural properies, some deviaions were made from he sandard es proedures; mos noably in he daa reduion. See referenes 2 and 3 for desripions of some of hese deviaions. Fiber volume fraions were deermined using he aid digesion 7

9 mehod. Glass ransiion emperaures were deermined using he Norhrop Grumman Corp. B2 Division proess speifiaion T-139A. The old and elevaed emperaures used for esing were -125 F and 180 F, respeively. 6.0 Tes Resuls Resuls of he esing are shown in Tables 6 hrough 13. For he mehanial and he bol bearing properies, mos resuls are he average of daa from six speimens. For he OHC, OHT, and CAI properies, mos resuls are he average of daa from hree speimens. However, due o he loss of some speimens (eiher due o esing or insrumenaion failure), some resuls are he average of daa from fewer speimens. The number of daa poins used o alulae a pariular propery is given in he ables. Normalizaion of fiber dominaed mehanial properies was performed wih respe o he measured ply hikness. The nominal ply hikness was deermined by averaging all he ply hiknesses of speimens used o deermine mehanial properies for eah maerial form. The normalized values were alulaed by he equaion Normalized Value = Measured Value x Speimen Thikness Nominal Thikness where he "Nominal Thikness" is he nominal ply hikness imes he number of plies in he laminae. The mehanial, sruural, and addiional properies of MR50/LTM25 are shown in Tables 6 hrough 9. Tables 6 and 7 presen he mehanial properies. Table 8 presens he sruural properies. Table 9 presens he addiional properies lised in Table 2. The mehanial, sruural, and addiional properies of CFS003/LTM25 are shown in Tables 10 hrough 13. Tables 10 and 11 presen he mehanial properies. Table 12 presens he sruural properies. Table 13 presens he addiional properies lised in Table 2. Proess speifiaion T-139A is proprieary o he Norhrop Grumman Corp. Thus, his proess speifiaion is no publily available and no referene an be given. 8

10 Referenes 1) Juska, Thomas; Loup, Doug; and Mayes, Seven: An Evaluaion of Low Energy Cure Glass Fabri Prepregs. CARDIVNSWC-TR-65-96/23, Naval Surfae Warfare Cener Repor, ) Posyn, A. S.; and Shah, C. H.: Propery Evaluaion of LTM25 Composie Maerials. NASA CR , ) Shah, C. H.; and Posyn, A. S.: Pin Bearing Evaluaion of LTM25 Composie Maerials. NASA CR , ) Anon.: Sandard Tes Mehod for Tensile Properies of Polymer Marix Composie Maerials, ASTM D3039, 1994 Annual Book of ASTM Sandards, Vol , Amerian Soiey for Tesing and Maerials, 1994, pp ) Anon.: Sandard Tes Mehod for Compressive Properies of Rigid Plasis, D695, 1996 Annual Book of ASTM Sandards, Vol. 8.01, Amerian Soiey for Tesing and Maerials, 1996, pp ) Anon.: Sandard Praie for In-Plane Shear Sress-Srain Response of Unidireional Polymer Marix Composies, ASTM D3518, 1994 Annual Book of ASTM Sandards, Vol , Amerian Soiey for Tesing and Maerials, 1994, pp ) Anon.: Polymer Marix Composies Vol. 1: Guidelines, MIL-HDBK-17-1D, U.S. Deparmen of Defense, February 1994, pp ) ACEE Composies Proje Offie: NASA/Airraf Indusry Sandard Speifiaion for Graphie Fiber/Toughened Thermose Resin Composie Maerial, NASA RP-1142,

11 10 Vauum Bag Sealan Vauum Bag Breaher Nonperforaed Release Film Laminae Nonperforaed Release Film Tool Figure 1. Laminae Bagging Layou

12 Table 1. Mehanial Properies Repored Propery E 2 E 2 s G 12 ν 12 ν 12 ν 21 ν 21 u u F 2 u F 2 u su 2 ε 1 u ε 1 u ε 2 u ε 2 u su γ 12 Desripion Longiudinal modulus, ension Longiudinal modulus, ompression Transverse modulus, ension Transverse modulus, ompression In-plane shear modulus Major Poisson's raio, ension Major Poisson's raio, ompression Minor Poisson's raio, ension Minor Poisson's raio, ompression Longiudinal ulimae sress, ension Longiudinal ulimae sress, ompression Transverse ulimae sress, ension Transverse ulimae sress, ompression In-plane shear ulimae sress Longiudinal ulimae srain, ension Longiudinal ulimae srain, ompression Transverse ulimae srain, ension Transverse ulimae srain, ompression In-plane shear ulimae srain Noe: All hese properies are repored for he CTD, RTD, and ETW ondiions. 11

13 Table 2. Sruural Properies Repored Propery Desripion Condiions br F p br F y br F u oh F u oh F u ai F u ai ε u Bol bearing proporional limi sress CTD, RTD, ETW Bol bearing yield sress CTD, RTD, ETW Bol bearing ulimae sress CTD, RTD, ETW Open-hole ompression ulimae sress RTD, RTW, ETD, ETW Open-hole ension ulimae sress CTD, RTD Compression-afer-impa ulimae sress RTD Compression-afer-impa ulimae srain RTD Table 3. Addiional Properies Repored Propery ρ V f nom dry T g we T g Mg α 1 α 2 Desripion Maerial densiy Fiber volume fraion Nominal ply hikness Glass ransiion emperaure, dry Glass ransiion emperaure, we Moisure gain from he dry o he we ondiion Longiudinal oeffiien of hermal expansion a room emperaure Transverse oeffiien of hermal expansion a room emperaure 12

14 Table 4. Tes Proedures for Mehanial Properies Propery Tes Proedure E 2 E 2 s G 12 ν 12 ν 12 ν 21 ν 21 u u F 2 u F 2 u su 2 ε 1 u ε 1 u ε 2 u ε 2 u su γ 12 ASTM D3039 ASTM D695 ASTM D3039 NAI-1504, Rev. C or ASTM D695 ASTM D3518 ASTM D3039 ASTM D695 ASTM D3039 NAI-1504, Rev. C or ASTM D695 ASTM D3039 ASTM D695 ASTM D3039 NAI-1504, Rev. C or ASTM D695 ASTM D3518 ASTM D3039 ASTM D695 ASTM D3039 NAI-1504, Rev. C or ASTM D695 ASTM D3518 Complee referenes for he ASTM es proedures are given in he Referenes seion of his repor. The NAI-1504, Rev. C es proedure is proprieary o he Norhrop Grumman Corp. Thus, his es proedure is no publily available and no referene an be given. See Seion 5 of his repor for addiional remarks on he es proedures. For he MR50/LTM25 (unidireional) maerial, he 3-in by 1-in ompression es speimen desribed in Norhrop Grumman Corp. maerial speifiaion NAI-1504, Rev. C, was used. For he CFS003/LTM25 (fabri) maerial, he ASTM D695 es proedure was used. 13

15 Table 5. Tes Proedures for Sruural Properies Propery Tes Proedure F p br F y br F u br F u oh F u oh F u ai ε u ai MIL-HDBK-17-1D MIL-HDBK-17-1D MIL-HDBK-17-1D NASA RP-1142 NASA RP-1142 NASA RP-1142 NASA RP-1142 Complee referenes for hese es proedures are given in he Referenes seion of his repor. See Seion 5 of his repor for addiional remarks on he es proedures. The es proedures speified in NASA RP-1142 are inended o be used wih unidireional maerials. In he presen work, he same es proedures were used for he CFS003/LTM25 fabri maerial, exep ha he laminaes used were [45/0/-45/90] 2s for he OHC and OHT ess, and [45/0/-45/90] 4s for he CAI ess. In addiion, he old and elevaed emperaures used in he presen work were -125 F and 180 F, respeively, insead of hose speified in NASA RP

16 Table 6. Measured Mehanial Properies for MR50/LTM25 Propery CTD RTD ETW ν 12 ν 12 E 2 ν 21 E 2 ν 21 s G (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (4) (6) (6) (6) (6) (6) (6) (6) (6) (5) (6) The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 15

17 Table 6. Measured Mehanial Properies for MR50/LTM25 - Conluded Propery CTD RTD ETW u u F 2 u F 2 u su 2 ε 1 u (µin/in) ε 1 u (µin/in) ε 2 u (µin/in) ε 2 u (µin/in) su γ 12 (µin/in) 279 (6) (6) (6) (6) (6) ,600 (6) 10,700 12, ,740 (6) 8,790 10, ,250 (6) 2,660 3, ,600 (6) 18,500 27, ,000 (6) 21,100 22, (6) (6) (6) (6) (6) ,800 (6) 11,300 12, ,660 (6) 6,670 8, ,900 (6) 2,440 3, ,200 (6) 22,700 28, ,300 (6) 20,900 22, (6) (6) (6) (6) (6) ,000 (6) 11,400 14, ,080 (6) 4,240 5, ,310 (6) 2,000 2, ,300 (5) 21,500 28, ,900 (6) 19,900 22, The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 16

18 Table 7. Normalized Mehanial Properies for MR50/LTM25 Propery CTD RTD ETW u u 20.9 (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 17

19 Table 8. Sruural Properies for MR50/LTM25 Propery CTD RTD RTW ETD ETW Fp br Fy br Fu br Fu oh Fu oh Fu ai εu ai (µin/in) 77.4 (6) (6) (6) (3) (6) (6) (6) (3) (3) (2) ,370 (2) 3,330 3, (3) (3) (6) (6) (6) (2) The numbers in parenheses nex o he mean values in his Table indiaes how many daa poins were used o alulae he pariular propery.

20 Table 9. Addiional Properies for MR50/LTM25 Propery Resuls ρ lb/in 3 V f 60.9% nom T g dry T g we in 265 F 218 F Mg 1.72% µin/in/ F α 1 α µin/in/ F Speimens esed for Tg dry were dried using he Norhrop Grumman Corp. ondiioning proedure. Speimens esed for T g we were ondiioned o approximaely 0.83% moisure onen using he Norhrop Grumman ondiioning proedure. See Seion 4.0. Speimens esed for his propery were ondiioned using he NASA LaRC ondiioning proedure. See Seion

21 Table 10. Measured Mehanial Properies for CFS003/LTM25 Propery CTD RTD ETW ν 12 ν 12 E 2 ν 21 E 2 ν 21 s G (6) (5) (6) (6) (6) (5) (6) (6) (6) (6) (6) (6) (5) (6) (6) (6) (3) (6) (6) (3) (6) (5) (6) (5) (6) (2) (6) The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 20

22 Table 10. Measured Mehanial Properies for CFS003/LTM25 - Conluded Propery CTD RTD ETW u u F 2 u F 2 u su 2 ε 1 u (µin/in) ε 1 u (µin/in) ε 2 u (µin/in) ε 2 u (µin/in) su γ 12 (µin/in) 76.1 (6) (6) (6) (6) (6) ,000 (6) 8,500 10, ,100 (6) 14,500 15, ,500 (6) 9,730 11, ,800 (6) 11,900 13, ,100 (6) 22,700 25, (6) (6) (6) (6) (6) ,100 (6) 9,550 11, ,900 (6) 12,400 13, ,400 (6) 10,700 12, ,800 (6) 9,830 12, ,600 (6) 28,800 30, (6) (6) (6) (6) (6) ,600 (6) 11,500 13, ,580 (6) 5,860 7, ,400 (6) 10,500 18, ,490 (6) 7,030 8, ,900 (6) 20,400 21, The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 21

23 Table 11. Normalized Mehanial Properies for CFS003/LTM25 Propery CTD RTD ETW E 2 E 2 u u F 2 u F 2 u 7.93 (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) (6) The numbers in parenheses nex o he mean values in his Table indiae how many daa poins were used o alulae he pariular propery. 22

24 Table 12. Sruural Properies for CFS003/LTM25 Propery CTD RTD RTW ETD ETW Fp br Fy br Fu br Fu oh Fu oh Fu ai εu ai (µin/in) 82.6 (6) (6) (6) (3) (6) (5) (5) (3) (3) (3) ,610 (3) 6,260 6, (3) (3) (6) (6) (6) (1) The numbers in parenheses nex o he mean values in his Table indiaes how many daa poins were used o alulae he pariular propery.

25 Table 13. Addiional Properies for CFS003/LTM25 Propery Resuls ρ lb/in 3 V f 46.9% nom T g dry T g we in 268 F 225 F Mg 2.03% 2.13 µin/in/ F α 1 α µin/in/ F Speimens esed for Tg dry were dried using he Norhrop Grumman Corp. ondiioning proedure. Speimens esed for T g we were ondiioned o approximaely 1.05% moisure onen using he Norhrop Grumman Corp. ondiioning proedure. See Seion 4.0. Speimens esed for his propery were ondiioned using he NASA LaRC ondiioning proedure. See Seion