dtic - defense technical information center tr 88-252 illustrations figgre pg 1 stress-strain data...

NSWC TR 88-252

AD-A233 061

STRENGTH AND FRACTURE CHARACTERISTICS OFHY-80, HY-1 00, AND HY-130 STEELS SUBJECTEDTO VARIOUS STRAINS, STRAIN RATES,TEMPERATURES, AND PRESSURES

BY T. J. HOLMQUIST(HONEYWELL INC.)

FOR NAVAL SURFACE WARFARE CENTERRESEARCH AND TECHNOLOGY DEPARTMENT

SEPTEMBER 1987

DTICApproved for public release; distribution is unlimited. f ELECTE

M AR 181 l91u

NAVAL SURFACE WARFARE CENTERDahlgren, Virginia 22448-5000 0 Silver Spring, Marylmnd 20903-5000

91 3 13 004

UNCLASSIFIEDSECLURITY CLASSIFICATION OF THIS PAGE

REPORT DOCUMENTATION PAGE1., REPORT SECURITY CLAVSVfICATnON . b, RESTRICTIVE MARKINGS

UNCLASSIFIED2& SECURITY CLASSIFICATION AUTHORITY S. DISTRIBUTION/AVAILABILITY OF REPORT

Approved for public release; distribution isak OIC.AMC5ATI•NIDOWNG.ON SHEDULE unlimited.

4. PERF•MING ORGANIZATION REPRT NUMIER(SI S. MONITORING ORGANIZATION REPORT NUMbER(S)

32415 NSWC TR 88-252

60, NAME OF PERFORMING ORGANIZATION "b. OFFICE SYMBOL 7&. NAME OF MONITORING ORGANIZATION

Honeywell Inc. Nv S a r e nArmament Systems Division Naval Surface Warfare Center

6L ADORESS (Chy. $Ma, ,nd P rC.de) 7b. ADDRESS (City, State. andZJP Code)

7225 Northland Drive 10901 New Hampshire AvenueBrooklyn Park, MN 55428 * Silver Spring, MD 20903-5000

ORGA NAME OP FUNONWSPONSOING Sb, O(fICE SYMBOL 1. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBERORGAN IZATION I(If appliFa bi.)

Naval Surface Warfare Center Code R12 N60921-86-C-0249

k. ADDRESS (Cty, Seat% and Z' Co&.) 10. SOURCE OF FUNDING NOS.

10901 New Hampshire Avenue ELEMENTO , NPROJ No.TASK NO UNIT

Silver Spring, MD 20903-5000 62314N RJI4W21 5

11.rTITLE d~e ¢# ~surG• t4O Strength and Fracture Characteristics of HY-80, I 1Y-100, and HY- 130 SteelsSubjected to Various Strains, Strain Rates, Temperatures, and Pressures

12. PERSONAL AUTHOR(S)

Holmquist, T. J.1la, TYPE OF REPORT 13b.TIMECOVEREO , DATE OP REPORT(Yr., Mo., D.a) 1S.PAC COUNT

Final PROM 09/86 TO 09/87 1987, September 6516. SUPPLEMENTARV NOTATION

17. COSATI CODES IL SUBJECT TERMS (Continue on reseta If necstsary and Identify by block number)

FIELD 60UP SUN. GR. Fracture ModelStrength ModelComputer Codes

19. AB1STAACT (Continue on recs itf tasja•y and identify by block number)

This report documents strength and fracture characteristics of II Y-80, H Y. 100, and HYY- 130 steelssubjected to various strains, strain rates, temperatures, and pressures. A series of torsion tests, Hopkinsonbar tests and quasi-static tension tests were performed to obtain constants for the strength and fracturemodels in the EPIC-2/EPIC-3 computer codes.

20. DISTNIUTIONIAVAILABIUITY OF ABSTRACT 2 1. ARSTRACI SECURITY CLASSIFICATION

MX UNCLASSIFIED/UNLIMITE [] SAME AS RPT. E] DTIC USERS UNC LASSI FIE D

22a. NAME OF RESPONSIBLE INDIV:DUAL 22b, TELEPHONE NUMBER 22c. OFFICE SYMBOL(Induil. Area Cod.)

Paula Walter (202) 394-2714 Code R12

DD FORM 1473, 84 MAR 83 APR edition may be used until exhausted _ ___NCLASS_ FI_ DAll other editions are obsolete SECURITY CLASSIFICATION OF THIS PAGE

li I i

UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS PAGE

UNCLASSIFIED7SECURIl Y CLASSIFICATION OF THIS PAGE

ii

NSWC TR 88-252

FOREWORD

This final report was prepared by Honeywell Inc., Armament SystemsDivision, 7225 Northland Drive, Brooklyn Park. Minnesota 55428, for theNaval Surface Warfare Center (NSWC), White Oak Laboratory, Silver Spring,Maryland 20903-5000, under contract N60921-86-C-0249.

This effort was conducted during the period from September 1986 toSeptember 1987. The NSWC Program Manager was Paula Walter.

The author would like to express his appreciation to LT Josef Smith for per-forming the Hopkinson Bar tests at Eglin Air Force Base, and to Gordon R. Johnsonand Craig Wittman of Honeywell for their contributions to his work.

The purpose of this contract was to obtain HY-80, HY-100, and HY-130 steelconstants for the strength and fracture models in the EPIC-2/EPIC-3 codes.

Approved by:

DR. KURT F. MUELLER, HeadEnergetic Materials Division

Acaession For

NTIS GRA&ID'IC TABUthiuiiouncod [

-u -t 'i (,I --.. rn..--.

By . . . .

iii/iv

NSWC TR 88-252

CONTENTS

section Page

1 INTRODUCTION ........................................... 1

2 TEST DATA............................ ................... 3

3- STRENGTH MODEL........................................ 17

4 FRACTURE MODEL........................................ 23

5 CONSTANTS FOR EPIC-2/EPIC-3 DATA LIBRARY .............. 35

6 SUMMARY ............................................... 41

REFERENCES............................................. 43

APPENDIX A--METALLURGICAL RESULTS OF flY-8O, HY-100,AND HlY-130 STEEL..................................... A-1

DISTRIBUTION............................................ (1)

NSWC TR 88-252

ILLUSTRATIONS

Figgre Pg

1 STRESS-STRAIN DATA FOR TORSION TESTS AT VARIOUSSTRAIN RATESFOR HY-80 STEEL ......................... 5

2 STRESS-STRAIN DATA FOR TORSION TESTS AT VARIOUSSTRAIN RATES FOR HY-100 STEEL ........................ 6

3 STRESS-STRAIN DATA FOR TORSION TESTS AT VARIOUSSTRAIN RATES FOR HY-130 STEEL ........................ 7

4 STRESS-STRAIN DATA FOR HOPKINSON BAR TESTS ATVARIOUS TEMPERATURES FOR HY-80 STEEL ............. 8

5 STRESS-STRAIN DATA FOR HOPKINSON BAR TESTS ATVARIOUS TEMPERATURES FOR HY-100 STEEL ........... 9

6 STRESS-STRAIN DATA FOR HOPKINSON BAR TESTS ATVARIOUS TEMPERATURES FOR HY-130 STEEL ........... 10

7 PHOTOGRAPHS OF THE FRACTURE PROFILES ON THEHY-80 STEEL HOPKINSON BAR SPECIMENS ... : .......... 11

8 PHOTOGRAPHS OF THE FRACTURE PROFILES ON THEHY-100 STEEL HOPKINSON BAR SPECIMENS ............. 12

9 PHOTOGRAPHS OF THE FRkCTURE PROFILES ON THEHY-130 STEEL HOPKINSON BAR SPECIMENS ............. 13

10 STRESS-STRAIN DATA FOR QUASI-STATIC TENSION ANDTORSION DATA FOR HY-80 STEEL ........................ 14

11 STRESS-STRAIN DATA FOR QUASI-STATIC TENSION ANDTORSION DATA FOR HY-100 STEEL ....................... 15

12 STRESS-STRAIN DATA FOR QUASI-STATIC TENSION ANDTORSION DATA FOR HY-130 STEEL ....................... 16

13 STRESS VERSUS STRAIN RATE FOR TENSION AND TORSIONT E ST S .................................................... 18

vi

NSWC TR 88-252

ILLUSTRATIONS (Cont.)

Figure

14 ANALYTIC STRESS-STRAIN RELATIONSHIPS FOR ISO-THERMAL AND ADIABATIC CONDITIONS FOR HT'-ee,STE EL ....................................... ............ 19

15 ANALYTIC STRESS-STRAIN RELATIONSHIPS FOR ISO-THERMAL AND ADIABATIC CONDITIONS FOR F1Y..-100STEEL .................................................... 20

16 ANALYTIC STRESS-STRAIN RELATIONSHIPS FOR ISO-THERMAL AND ADIABATIC CONDITIONS FOR HY-130STEEL ..................................................... 21

17 AVERAGE FRACTURE STRAIN VERSUS STRAIN RATE FORTENSION AND TORSION TESTS FOR HY-80, HY-100, ANDHY-130 STEEL ............................................ 24

.18 PRESSURE-STRESS RATIO VERSUS EQUIVALENT STRAINFOR THE TENSILE SPECIMENS ........................... 25

19 FRACTURE STRAIN VERSUS PRESSURE-STRESS RATIO FORISOTHERMAL QUASI-STATIC CONDITIONS ............... 27

20 EFFECTS OF STRAIN RATE AND TEMPERATURE ON FRAC-TURE STRAINS ........................................... 28

21 FRACTURE STRAIN AS A FUNCTION OF PRESSURE-STRESSRATIO, STRAIN RATE, AND TEMPERATURE FOR HY-80STE E L .................................................... 3 0

22 FRACTURE STRAIN AS A FUNCTION OF PRESSURE-STRESSRATIO, STRAIN RATE, AND TEMPERATURE FOR HY-100STEE L .................................................... 31

23 FRACTURE STRAIN AS A FUNCTION OF PIW SSURE-STRESSRATIO, STRAIN RATE, AND TEMPERATURE FOR HY-130STE EL .................................................... 32

24 DATA STATEMENTS FOR THE EPIC-2/EPIC-3 MATERIALLIBRARY IN ENGLISH UNITS ............................. 36

25 EPIC-2fEPIC-.3 PREPROCESSOR OUTPUT FOR THE MATERIALDATA IN ENGLISH UNITS FOR HY-80 STEEL .............. 37

26 EPIC-2fEPIC-3 PREPROCESSOR OUTPUT FOR THE MATERIALDATA IN ENGLISH UNITS FOR HY-100 STEEL ............. 38

27 EPIC-2fEPIC-3 PREPROCESSOR OUTPUT FOR THE MATERIALDATA IN ENGLISH UNITS FOR HY-130 STEEL ............. 39

vii

NSWC TR 88-252

TABLES

Table Page

1 PHYSICAL PROPERTIES OF HY-80, HY-100, AND HY-130STE E L .................................................... 4

2 SUMMARY OF STRENGTH AND FRACTURE MODEL CON-STANTS FOR HY-80, HY-100, AND HY-130 STEEL .......... 33

v

viiii

NSWC TR 88-252

SECTION I

INTRODUCTION

This report documents the strength and fracture characteristics of HY-80,HY-100, and HY-130 steels, subjected to various strains, strain rates, temperatures,and pressures. The result of this characterization is the generation of constants forthe strength and fracture models in the EPIC-2 and EPIC-3 codes. 1,2

The following sections describe the test data and the analysis of the data usedto obtain constants for both the strength and fracture models.

1/2

NSWC TR 88-252

SECTION 2

TEST DATA.

The test data were obtained from torsion tests at various strain rates,Hopkinson bar tension tests at various temperatures, and quasi-static tension testswith various specimen geometries (notched and unnotched). The torsion tests wereperformed with the Biaxial Testing Machine at Southwest Research Institute, theHopkinson bar tests were performed at Eglir. Air Force Base, and the quasi-statictension tests were performed at Honeywell. The HY-80, HY-100, and HY-130material was provided by the Naval Surface Warfare Center (NSWC). Physicalproperties are given in Table 1.3 Metallurgical data are shown in Appendix A.

Torsion data are shown in Figures 1 to 3. Comparable data for 12 othermaterials are presented elsewhere.4 ,5 Some desirables features of this testingtechnique are that the state of stress in the specimen is well defined, large strainscan be achieved without forming geometric instabilities, and a wide range of strainrates can be obtained with the same testing technique. It appears that adiabaticthermal softening is causing the lower stresses at the higher rates.

Figures 4 to 6 show Hopkinson bar test data at various temperatures. Theelevated temperatures are obtained by surrounding the in-place test specimen by anoven such that the temperatures are applied for several minutes prior to testing.Although it is possible to test materials to greater strains than those shown inFigures 4 to 6, the Hopkinson bar data cannot be accurately evaluated after neckingbegins in the ten3ile specimens. Furthermore, at larger strains the effects ofadiabatic heating can also complicate the results. The elevated temperatures show adistinct softening effect on the strength of the materials.

Photographs of the fractured Hopkinson bar specimens are shown inFigures 7 to 9. rhe cross-sectional area of these surfaces can be used to obtainfracture characteristics.

Quasi-static stress-strain data for both tension and torsion tests are shown inFigures 10 to 12. An equivalent tensile flow stress is obtained from the torsion databy using the von Mises flow rule, the te~nsile stress is a = V3/3, and thecorresponding tensile strain is e = y/V3.

The stress for the tension test data is based on the current area of the neck, andthe strain is defined as in (Ao/A), where A. and A represent the initial and currentareas of the neck. The notchYd tension bars give a concentration of hydrostatictension in the test specimen.

This is clearly shown in the data of Figures 10 to 12. For a specified true strain,the stress (inchlding hydrostatic tension) increases for the notched geometry. It canalso be seen that the presence of the hydrostatic tension significantly decreases thestrain at which the material fractures.

" = • !

NSWC TR 88-252

TABLE]. PHYSICAL PROPERTIES OF IIY-80, I Y-lOO, AND HY-130 STEEL

HY-O STEEL HY-100 STEEL HY-130 STEEL

HARDNESS (ROCKWELL) C-21 C-25 C-30

ELASTIC PROPERTIES

ELASTIC MODULUS, E (OPA) 207 207 207

POISSON'S RATIO, ' .30 .30 .30

-SHEAR MODULUS, E/ 2 (1 + 1) (GPa) 79 79 79

BULK MODULUS, E / 3 (1 - 2-0) (GPa) 172 172 172

THERMAL PROPERTIES

DENSrITY, p (kg/m*) 7746 7748 7885

CONDUCTIVITY, k (W/mK) 34 34 27

SPECIFIC HEAT, c p (JftgK) 502 502 489

DIFFUSIVITY, k/pcp (m 1/s) .000009 .000009 .000007

EXPANSION COEF. (VOL.), a (K"1 ) .000011 .000014 .000013

MELTING TEMPERATURE, TMM.T (K) 1793 1793 1793

N07.020,JF

-- ,i

4,

NSWC TR 88-252

Soo

HY-80 STEEL

700

400

AVERAGE SHEAR STRAIN RATESJ (S-9)

300 -H-I b3-.2MM? ORIO

200

100

0

0 .5 1.0 1.5 2.0 2.5 3.0

AVERAGE SP~'EAR STRAIN, Y =RO /L

[IGU RE 1. STRESS-STRAIN DATA FORTRoiSI ON TESTS AT VARIOUS ST1RAINHATES FOR IIY-80 STFEEL

5

NSWC TR 88-252

800

7001- HY100 STEEL

400 .01

0 ~~AVERAGE &+-EAR STRAIN RATES,~s'

-*w -3.2mm

P(T~h 2~7~~TORSION4(9 ý SPECIMEN

200 o~m

10

0.6 1.0 1.5 2.0 2.5 a

AVERAGE St-EAR STRAIN, P7 - RO /L

F1XGURE 2. SrVRIESS-SrVRAIN DAT'A FOR T'ORSION TEýSTIS AT VARtIOUS S'TRAINRATES FOR H-IY- 100 STEEl1.

6

NSWC TR 88- 252

800

Hy-130 STEEL

34. U3 10.

~4OOAVERAGE Sl-F- STRAWl RATESTCfS-1)

~300

TORSIONSPECIMEN

200 -0,9mm

I---syMM --- *4

100

00 .6 1.0 1.5 2.0 2.5 3.0

AVERAGE SH-EAR STRAt'J1 7 - RO A-

FIGURES3. STRIESS-STRA] N DAT'A FOR TORSION TESTIS AT VARIOUS STE'IAlNRATES FOR HY-130 STEEL

,A7

NSWC TRr 88-252

14.00 I

HY-80 STEEL1200

THERMAL SOFTENINJG DATA1000 -TAKEN AT e - .08

1000-ý4

9-668 T*113.15

6800 T*u .2 5T4= .35

1.0

T*FMELT -TRoom KT

200

0

0 T* 1.

0.0 .08 .16 .24 .32 .4o

TRUE TENSILE STRAIN, c = ba AI0)

FIGU RE 4. STRESS-STRAIN DATA FlOR IIOPK INSON BAR TESTS ATVARI OUS TEMPERATURES VOR II Y-80 STEEL

NSWC TR 88-252

1400

HY-100 STEEL

1200 THERMAL 8OFTENING DATATAKEN AT e a.Ta

* -- •:•" "9-521S-1 2-.-2.mu["u

1000 ST IPECIME

/ 547 IT*- 0.0

2800-

TT 1.0

O6 0 T *=1 .2 5 2 4

STooK78

200T.

.01.

40TRUE TENSLE STRAIN, E = TM

(T /1 )

FIGURE 5. STRESS-STPRAJN DATA FOR 11 OKI~INSON BAR TESTS ATl VA RI OUS

TEMPERATURES -OR I Y-T SoTEE

KT \N

NSWC TR 88-252

1400

HY-130 STEEL

THERMAL SOFTENIIG DATA1200TAKEN AT .08

Z 623 s"' ."m Cm

1000. .6 TEST SPECIMEN

CoS800 T*= 0.0

T*- .15T-.35

z 600W" T*- .25

1.0 1 T

400T* .. T " TROOM r

TmELT "T KT

200

00 T 1.0

0

0.0 .08 .16 .24 .32 .40

TRUE TENSILE STRAIN, e = L% (1/1o)

FIGURE 6. STRESS-STRAIN DATA FOR IHOPKINSON BAR TESTS ATVARIOUS TEMPERATURES FOR I IY-1 30 STEEL

10

I I I I II I I I

NSWC TR 88-252

Tý=.25

441~

101GUIUE 7. P1 IIOrIlOORAPýII.IS 01' ill'1!EFItAC'I'U REi, PROF'ILE'SON TI IICIY-8OSTEEL HIOPKINSON BAR SPECIMENS

NSWC TR 88-252

1~.25

..... .......

FIGURE'8. P)IIOTOGRtAPliIS 011'il' TI v ACTIURtE IlROFILES ON rjl viiylo 100SThEM HOPKINSON I3AR SPECIMENS

12

NSWC TR 88-252

mmm 1

F'IGUREM9 P1 IOTOGRIAPIIS OP TIlIIý FRACTIURE PRiOFILES ON TI I E 'II Y-130STE'EL HIOPKINSON BAR SPECIMENS

13

NSWC TR 88-252

2000

1800 NOTCHED TENSION BAR DATA

15.2 tv F6m TESTlaw mM n .IM ýSPECIMEN

SMOOTH BAR TENSION TESTDATA (0 P,.002 Sf-)

.1400

EQUIVALENT TENSILE FLOW1200 - STRESS FROM SMOOTH BAR

TENSION TEST DATA (BRIDGMAN)

1000 EQUIALENT TENSILE FLOWSTRESS FROM TORSION DATA(VON MISES)

S800

600 •

TORSION DATA_ ~(p'.01 8'

400

HY-80 STEEL200

_-0 I .... I

0 .5 1.0 1.5 2.0 2.5 3.0

TRLE PLASTIC STRIAN

FIGUIRIE 10. S'ITRESS STRAIN D)ATA FOR QUASI -STATIC TENSION ANDTOIRSION I)ATA FOI1 IY 80 STEEL

14

NSWC TR 88-252

2000

NOTCHED TENSION BAR DATA18004At ~/ R - 2.5MM--

7.6MM TESTSPECIMEN

+SMOOTH BAR TENSION TEST DATA(1;,.002 S'

1400 ~

EQUIVALENT TENSILE FLOW STRESSt FROM SMOOTH BAR TENSION TEST

1200 DATA (BRIDGMAN)

EQUIVALENT TENSILE FLOW STRESS1000 - FROM TORSION DATA (VON MISES)

800

600 - ------

TORSION DATA400 - .0o- S")

HY-100 STEEL

200

o0 I I , 11l . .

0 .5 1.0 1.5 2.0 2.5 3.0

TRUE PLASTIC STRIAN

FIGURE8 1. STRESS-STRAIN DATA FOR QUASI-STATIC TENSION ANDrORSION DATA FOR iiY-Io1 STEEL

15

NSWC TR 88-252

2000 1 1 ,NOTCHED TENSION BAR DATA

jr~amm TEST

1800 s 6.im a SPECIMEN

SMOOTH BAR TENSION TEST DATA

1600

1400 - EQUWVALENT TENSILE FLOW STRES3V FROM SMOOTH BAR TENSION TEST

DATA (BRIDOMAN)

1200

EQUIVALENT TENSILE FLOWSTRESS FROM TORSION DATA(VON MISES)

1000Co

800

600

TORSION DATA(•-.01 S)

400

HY-.130 STEEL

201

0 .5 1.0 1.6 2.0 2.5 3.0

TRUE PLASTIC STRIAN

FIGURE 12. STRESS-STRAIN I)ATA FOR QUASI-STATIC TENSION ANDTORSION DATA FOR IIY-130 STEEL-

16

NSWC TR 88-252

SECTION 3

STRENGTH MODEL

The origin of the strength model, and the techniques used to extract constantsfor the model, are described in References 7 and 8. The analysis which follows isessentially identical to that described in these references.

The model for the von Mises flow stress, a, is expressed as

a = IA + Brn"11 + CIni*jll - T*(1)

where E is the equivalent plastic strain, 0* = O/to is the dimensionless plastic strainrate for to = 1.0s1 and T* is the homologous temperature. The five material con-stants are A, B, n, C, m. The expression in the first set of brackets gives the stress asa function of strain for 0* = 1.0 and T* = 0. The expressions in the second and thirdsets of brackets represent the effects of strain rate and temperature, respectively.The basic form of the model is readily adaptable to most computer codes since it usesvariables (e, 0, T*) which are available in the codes.

The first step in the process is to determine the constants in the first set ofbrackets. A is the yield stress and B and n represent the effects of strain hardening.Since the torsion data in Figures 1 to 3 include the strain rate of interest (U* = 1.0),it is a straightforward procedure to obtain the appropriate constants for this strainrate.

The same three constants can also be derived from the quasi-tension data ofFigures 10 to 12. These results are for 0* = 0.002 and must therefore be adjustedfor &* = 1.0. This can readily be accomplished after the strain rate constant, C, isdetermined.

Figure 13 shows the effect of strain rate for tension and torsion. In both casesthe stress increases as the strain rate increases. The results are shown for relativelysmall strain values (c = 0.08, y = 0.20) to ensure that the strain rate effect is notsignificantly altered by adiabatic thermal softening. Strain rate constants for bothtension and torsion can be determined from the 'least squares' linear approximationsof the data.

The effect of thermal softening is shown in Figures 4 to 6. The thermalsoftening fraction, Kt = 1 - TVn, is simply the ratio of the stress at elevatedtemperature to that at room temperature. The thermal softening constant, mn, isshown to give an analytic expression which closely matches the experimental data.

17

NSWC TR 88-252

At thispoint there are two sets of constants (tension and torsion) for strain andstrain rate effects (A, B, n, C) and one constant, re,for the thermal softening.Averaging the tension and torsion constants for strain rate effects gives a final set ofconstants (A, B, n, C) to be used in the strength model. The resulting stress-strainrelationships are shown in Figures 14 to 16.

It can be seen that the strength results for the three materials are wellbehaved. As expected, the HY-80 steel has the lowest strength and the HY-130 hasthe highest strength. The yield stresses, A, increase when going from the HY-80 tothe HY-130; the strain rate effects, C, decrease when going from the HY-80 to theHY-130; and the thermal softening effects, m, are essentially identical for all threematerials.

1400

1200 TENSION DATA (e .08)

Hy- 1 30

1000 -H-0

HY-80

800l4600 HY-130---

HY IO .. _ J . ............

HY-80

400 HYBO -

TORSION DATA (7-..20)

200-40

0 _ I I I . . . I ... .

.0001 .001 .01 .1 1.0 10 100 1000

STRAIN RATES, 9 AND¶' (S-1)

FIGURE 13. STRESS VERSUS STRAIN RATE FORTENSION AND TORSION

THIS18

NSWC TR 88-252

1600

1400 STRAENRATE,~(100,000

ISOTHERMAL`"AT.E 10,0001,000

1200

~101000

o[672+425 ~1 +.014br Lemt] T*. 4

~600

400-

HY-80 STEEL200

S0 . . . I I I, I•I ,

0.0 .25 0.5 .75 1.0 1.25 1.5 1.75

TRUE TENSILE STRAIN, C

FIGURE 14. ANAI,YTIC STRESS STRAIN RELATIONSIIIPS FOR ISOTIIERMALAND ADIABATIC CONDITIONS FOR I-IY-30 STEEL

Z1

NSWC TR 88-252

1400 STRAIN RATE,(8

1200

~00,00

o 800-

aa[758 +402P.281[I+ .()II Ai~[- T* IA

1600-

HY-100 STEEL200

0.0 26 0.5 .15 1.0 1.25 1.5 1.75TRUE TENSIL STRAt'J e

FIGURE 15. ANALYTIC STRESS-STRAIN RE1LATIONSi ips FOR ISOTHERMALAND AD)IABATIC CONDITIONS FORl H Y-100 STEEL

20

NSWC TR 88-252

1600

STRAIN RATE, I (Sl

1400 IOHFA

1200

'~1000

~800

600 -[920 +333 1~]f +.008 6 j*[1 T.T

400

HY-130 STEEL200

0.0 .25 0.5 .75 1.0 1.25 1.5 1.75

TRUE TENSILE STRAIN, C

FIGURH'16. ANALYTIC STRESS-STRAJN HELATPIONSHIPS FOR 150Thl WERAWAAND) ADIAI3ATIC COND)ITIONS FOR 11Y- 130 STEEL

21/22

NSWC TR 88-252

SECTION 4

FRACTURE MODEL

The origin of the fracture model and the techniques used to obtain the appropriate constants are presented in References 7 and 9. As was the case with thestrength constants, the fracture constants are obtained in a manner similar to thatpresented in these referencest

To begin, the damage to an element is defined as

) - -(2)

where Ac is the increment of equivalent plastic strain which occurs during anintegration cycle, and cc is the equivalent strain to fracture, under the currentconditions of strain rate, temperature, pressure and equivalent stress. Fracture isthen allowed to occur when D = 1.0.

The general expression for the strain at fracture is given by

el'= [I)1 + l) 2 oxp l) 30*111 + D4 1n0*]I1 + D IIT*I (3)

for constant values of the variables (0*, t*, T*) and o* < 1.5. The dimensionlesspressure-stress ratio is defined as 0* = am/5 where am .-1 the average of the threenormal stresses anm B is the von Mises equivalent stress. The dimensionless strainrate, &* and homologous temperature, T*, are identical to those used in the strengthmodel of Equation (1).

The five constants are D1 ...D5 . The expression in the first set of bracketsfollows the form presented by Hancock and Mackenzie.10 It essentially says that thestrain to fracture decreases as the hydrostatic tension, am increases. The expressionin the second set of brackets represents the effect of strain rate, and that in the thirdset of brackets represents the effect of temperature. For high values of hydrostatictension ( a* > 1.5), cris linearly interpolated between egat o* = 1.5 and Efpnin at0* = Ospall/U, where Ospall and ejrnin are input values of spall stress and strain.7,'

The first step required to obtain the fracture constants is to determine theeffect of the dimensionless pressure-stress ratio, o*. This can be done by consideringthe quasi-static tension and torsion data of Figures 10 to 12 and 17. For the torsiondata o* = 0 and for the unnotched tension data o* = 1/3. For the notched tensionbar, EPIC-2 simulations were performed to compute o* at the center of the specimen.These results are shown in Figure 18. For these computations, an average pressurefor each set of adjacent triangular elements was used to eliminate any excessivestiffness due to the triangular element formulation. II

23

NSWC TR 88-252

- - - TENSV. DATAvs t

2.5 - TORSPN DATA

(vs)

2.0 A

• 1.50A

to --. . ..-------- 0 HY--80Z a .... -W HY-130

- -.... ---- -- -- A- HY-100

~1.0<.QiAS-TATIC HOPKINSON BAR, ,w TESIN DATA

> TENSION DATA

0.5

0 I I I I J . . t . .

.0001 .001 .01 .1 1 10 100 1000 10000

AVERAGE STRAIN RATES, TANDT'(S-

FIGURE 17. AVERAGE FRACTURE STRAIN VERSUS STRAIN RATE FORTENSION AND TORSION TESTS FOR 1-1 Y-80, 1I Y-100,AND HY-130 STEEL

24

NSWC TR 88-252

1.6

dINIIAL acOMiruqy

COMPUTED RESULTS FOR' U ý

1.4 NOTCHED TENSION BAR

'1.27 HY-100 '~HY-80

o COMPUTED GEOMETRY AT FRACTURE

U..1.00 MM

00.8HY-80 HY- 100 HY-130

< HY-130 HY-80

0.6 HY-100

o .4D BRIDGEMAN FACTOR FOR

UNNOTCHED TENSION BARCL

0.2 -

0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

EQUIVALENT STRAIN AT CENTER, E

FIGURE 18. PRESSURE-STRESS RATIO VERSUS EQUIVALENT STRAIN FORTIHI TENSILE SPECIMENS

25

NSWC TR 88-252

For the notched tensions bars, the computed pressure-stress ratio begins atapproximately o* = 0.8 and peaks somewhere between o* = 1.3 to 1.4, depending onthe material. After its peak the pressure-stress ratio gradually decreases untilfracture. It should be noted that each curve's maximum pressure-stress ratio is in thesame order as their respective strengths.

Figure 19 shows the equivalent plastic strain to fracture as a function of thepressure-stress ratio for quasi-static conditions. For all three materials an apjproxi-mate analytic fit to the data was performed by setting D3 = -0.5, and solving orD1 and D2.

Figure 20 shows the effect of strain rate and temperature on the strain tofracture. The fracture strains are expressed as the ratio of the Hopkinson bar frac-ture strains divided by the quasi-static tensile fracture strains. The Hopkinson barfracture strains are approximitely determined by measuring the cross-sectional areaof the post-tested specimens as shown in Figures 7 to 9. Unfortunately, these areascannot be measured with a high degree of accuracy. The temperatures for each testrange from the initial temperature at the beginning of the test to the computedtemperature at the strain where fracture occurs.

For example, in Figure 20, for the first test performed on the HY-100 materialthe specimen was initially at room temperature (T* = 0). If all the plastic work isconverted to adiabatic heat, the computed final temperature is 606K (T* = .21). Thestrain at-which this specimen fractured was cf = 1.13, at an average strain rate oft 550s 1. The quasi-static (t - .002s-0), room temperature (T* = 0) tension test isused as the normalizing denominator for the vertical axis. For the HY-100 materialthis fracture strain is ef = 1.04. The ratio of these two fractures strains is 1.09 and isthe value plotted on the vertical axis. The same procedure is used for the remainingthree HY-100 tests with the only difference being the initial temperature of thespecimen.

Under normal conditions a linear least squares fit is performed on the data ofeach material in Figure 20, of which the intercept is the strain rate'influence onfracture and the slope is the temperature influence. The HY-80, HY-100, andHY-130 materials acted differently than expected, displaying a consistent trend ofreaching a peak fracture strain ratio between. 15T* and .35T* and then becomingless ductile as the temperature is increased (Figure 20). Possible explanations for thisbehavior is that the material becomes strain rate sensitive at higher tempera-tures as shown in Figure 17, or it may be experiencing a phenomena referred to as'temper embrittlement' where under certain tempering processes a metal becomesless ductile.

The current fracture model was not developed to handle the phenomena whichis occurring with the HY materials. By applying the linear least squares fit to thedata, one obtains deceiving results, implying that the material is very strain ratesensitive and loses ductility as the temperature increases. A more realistic approachto incorporate this data into the fracture model is to obtain an 'average' strain ratecoustant and neglect thermal effects. In graphical terms, fit the best horizontal lineto the data points of each material as shown on the right hand side in Figure 20.

Now the fracture constants can be determined. The strain rate constant, D4, isobtained by averaging the fracture strain ratios of Figure 20 for each respectivematerial. The average strain rate constant for all three is greater than 1.0. This

26

NSWC TR 88-252

3.0

2.5

C,

E2.0 HY-8O STEEL***

I- 1.0 5

TORSIONDT

QQAAS-STSICAOTCH

TENSION TEST DATA

0 1 . I I I I 1 - 11

-0.2 0.0 0.2 0.4 0,6 0.8 1.0 1.2 1,4

PRESSURE-STRE~SS RATIO, cy* =a, 11C

FIGURE 19. FRACTURE STPRAIN VERSUS PRESSURE-STIRESS RA'rIO FORISO'VhERMAL QUASI-STATrIC CONDITIONS

27

NSWC TR 88-252

1.4 p

O- HY-80 STEEL

A--& HY-O00 STEELS1.3o U-U HY-130 STEEL

0z 1.2AVERAGE RATIO$

- Y-100

S. ------HY-130

1-0

Z OpuI~TE TEPERATUREAT FRACTUREOIT TEMPERATURE OFI

NTILHOPKINSON BAR TEST

0.8 , .. . .•t•. ..0 O,1 0.2 0.3 0.4 045 0.0 0.7

DIMENSC)NLESS TEMPERATURE, T*

FIGURE 20, EFFECTS OF STRAIN RATE ANDFTEMPEIATUIE ON FRACTUR1'

STRAINS

28

NSWC TR 88-252

ratio indicates that the strain to fracture, ir ,reases slightly as the strain rateincreases. This same trend is verified by the fracture data of Figure 17, (Thedecrease in fracture strains for the higher strainwrate torsion data may be due toshear localizations resulting from adiabatic heating.4,5) The constants related to thepressure-stress ratio (D1, D2, D3) are those of Figure 19, adjusted from quasi-staticconditions (t = .002s 1) to 0- = 1.0. Finally, the temperature constant, D5, is set tozero, due to the unconforming data of Figure 20. The resulting relationships areshown in Figures 21 to 23.

Unlike the strength relationships, which transitioned in a well-behavedmanner from HY-80 to HY-130, the fracture characteristics do not follow a well-behaved pattern. The HY-80 steel exhibits the most ductility, as expected, but the-HY-100 is the least ductile. Generally, it would be expected that the higher strengthHY-130 steel would exhibit less ductility. The reasons for this apparent discrepancyare not clear.

Although no tests were performed to obtain spall characteristics of HY-80,HY-100, and HY-130, it is necessary to designate a spall stress and strain to completethe model. Based on comparisons with materials of similar yield strengths, the spallstress and strain were estimated and are shown in Table 2.

29

lO'l l '! •! • • ,••l"l'I•1 '• I q ••'r P

NSWC TR 88-252

3.0

HY-80 STEEL

2.0 . -[-,85 -2.70EXP 0 ][1 +.006 i.L' ](1 +0.0T*

1.N5

1.0

.

--- •mI18-1

0-0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

PRESSURE-STRESS RATIO. a* = % /'d

FIGURE 21. FRACTURE STRAIN AS A FUNCTION OF PRESSURIE-STRESSRATIO, STRAIN RATE, AN I) TEMPERATURE FOR IIY-80STEEL

30

NSWC TR 88-252

3.0

HY-100 STEEL

23

2.0

et [-.61 +2.07EXP 45s'][1 +.010 fmtn ][1 +o.orjS1.5 -

1.0

o0 .5 - u lops-,

0 t . I i ii ,

-0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

PRESSURE-STRESS RATIO, or* = /'

FIGURE 22, FRACTURE STRAIN AS A FUNCTION OF PRESSURE-STRESSRATIO, STRAIN RATE, AND TEMPERATURE FOR II Y-100STI'E EL

31

NSWC TR 88-252

3.0

2.6 HY- 130 STEEL

i 2.0

1.0- • ,-

0.1

0.

0 . . I I I I I

-0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

PRESSURE-STRESS RATIO, G* = 0/ /

FIGURE 23. FRACTURE STRAIN AS A FUNCTION OF PIESSURE-STRESSRATIO, STRAIN RA'I'T, AN!)" rIMPE' A' 'UJ{ FOIZ11Y-130STEEL

32

NSWC TR 88-252

TABLE 2. SUMIMARY OF STRENGTJI AND FRACTURE MODEl, CONSTANTSFOR IIY-80, IIY-100, AND HY-130 STEEL,

"HY-80 STEEL HY-100 STEEL HY-130 STEEL

STRENGTH CONSTANTS FOR'- [A +B B C•n 1 +iCn *] (1 -T*m]A (MPa) 672 758 920B (MPa) 425 402 333n .36 .26 .39C W014 .011 ,008m 1.14 1,13 1,15

FRACTURE CONSTANTS FOR

&.I P,[ +D2 EXP 03o* ][1+D 4 1n'el][ +DT ]D -.85 -.61 -.69D2 2.70 2.07 2.39

-0.50 -0.50 .0.50D 4 .006 .010 .004D ' 0.0 0,C 0.0SPALL STRESS, aSPAL. (MPa) 5500 5600 5900I m"h .033 .034 .036

! " Sc% ZeCA,, FOR *£ -10 -

N07-021 .JF

33/34

NSWC TR 88-252

SECTION 5

CONSTANTS FOR EPIC-2/EPIC-3 I)ATA LIBRARY

A sunmmary of the strength and fracture model constants is given iii Table 2.Data statements for the EPIC-2/EPIC-3 material library (Subroutine MATLIB) areshown in Figure 24, and the corresponding Preprocessor output is shown inFigures 25 to 27.

35

fL

NSWC TR 88-252

CY * H-80 STEEL *********u,*****~*aTJki .- AUG 1987

C **LIMITED TO U.S. GOVERNMENT AGENCIES ONLYC PRESSURE - KOHIN, AFWL-TR-69-38, 1969, P. 140 (STAINLESS STEEL 304L)C STRENGTH - HOLMQUIST, NSWC REPORT 1987C FRACTURE - HOLMQUIST, NSWC REPORT 1907C SPALL - OVERESTIMATED FROM DATA IN AFWAL-TR-61-.4040, 1981

DATA MTýYPE(25)/1/,IDAM( 25)/Of, IFAIL(25)/O/,EFAIL(25)/999./.1 DEN(25)/.000725/,BPH(25)/433000./,CDUCT(25)/4.32/,2 ALPMA(25)/.0000063/,TZMP1(25)/70./,TROOM(25)/70.'/,3 TREL'I(25)/2768./,CO( 25)/.02/,G( 25 )/11240000 ./,4 C1( 25)/97460./,C2(25)/61640./,AN( 25 )/.36/,C3(25 )/. 014/,t

5AW(25)/I. 14/,C4( 25)/O./,C5(25)/O ./,C(25)/23776000./,6 DC25)/42693000./,S(25)/72513000./.GRUN(25)/1.16/,71 Q1( 25)/.2/,Q2C25)/4./,PMIN(25 )/10000000./,C9(25)/O./,a Dl(25)/-.85/,D2(25)/2.70/oD3( 25)/-.50/,D4(25)/.006/,9 05( 25)/O.OO/,PFAzL(25)/795OOOý/,ZFMzIq(25)/.033/,ClO(25)/O./,A (DESCM(25,3)5 3-1,4) /4H*HY-,4HBO S,4HTEEL,4H /IB (DZsCm(25,j),J-'5,8) /4H. ,4H ,4HRC-2,4Hl /.C (DESCM(25,J),J7-9,12)/4H ,4H ,4H ,4H /

CC B Y-100 STEEL ****************A* TJH -AU(. 1987C LIMITED TO U.S. GOVERNMENT AGENCIES ONLY

C PRESSURE - KOHN, AFWL-TR-69-38, 1969, P. 14U (STAINLESS STEEL 304L)C STRENGTH - HOLMQUIST, NSWC REPORT 1987C FRACTURE - HOLMQUIST, NSWC REPORT 1987C SPALL - OVERESTIMATED FROM DATA IN AFWAL-TR-81-4040, 1981

DATA MTYPE (26)/1/, 1DAM ( 26 1/0/,IT A L ( 26) /0/,EFAIL (2 6 )/9 99./I DEN (2 6) /.0 0 07 25/, SPH (2 6 )/4 33 00 0./,CDUCT ( 26 )/4. 32/,2 AL PRA (26)/. 00 0 0 077/, TEMP 1 ( 26 ) /70 Q. / TROOM ( 2 6 ) /7 0./3 TMELT(26)/2768./,CS(26)/.02/,GC26 )/11240000,/,4 C I(N ) /109 9 ./, C 2(26) /5 8 3 0. /,AN ( 26 ) /. 26/, C 3(26)/ 011/,5 AM(26)/1.13/,C4(26)/O./,C5(26 )/O./,C(26)/23776000./,6 D(26)/42693000./,S(26),'72513000./,GRUN(26)/1.16/,7 Q1(26)/.2/,02(26)/4./,PMIN(26 )/10000000./,C9(26)/O./,8 D 1(2 6)/-. 61/, D2 (2 6)/2.07 /, D3 ( 26 )/-. 50/, D4(2 6 )/. 010/,9 D 1 2 6)/0 . OO/ ,P TAI L(2 6)/819 3 00 ./, EFM I N(2 6)/. 0 34/, C 10( 26)/0./A (DESCM(26,J),J-1,4) /4H*HY-,4HlO0 ,4HSTEE,4HL /B (DESCM(26,J),J-5,8) /4H ,4H ,4HRC-2,4HS /C (0ESCM(26,J),J-9,12)/4H ,4H ,4H ,4H /

CC P** HY-130 STEEL TJH - AUG 1987C ** LIMITED TO U.S. GOVERNMENT AGENCIES ONLYC PRESSURE - KOHN, ATWL-TR-69-38, 1969, P. 140 (STAINLESS STEEL, 304L)C STRENGTH - HOLMQUIST, NSWC REPORT 1987C I-RACTURE - HOL.MQUIST, NSWC REPORT 1987C SPALL - OVERESTIMATED FROM DATA IN ArWAL-TR-81-4040, 1981

DATA MTP(7//IA(7//IAI(7//EAL2)99/1 DEN(27)/.000738/,BPH(27)/422000./CDUCT(27)/3.46/,2 ALPHA(27)/.0000073/,TEMP1(27)/70./TROOM(27 )/70./,3 TMELT(27)/2768./,C8(27)/.02/,G(27)/112

4 0 00 0 ./,4 Cl( 2 7)/13340O./,C2(27)/48300o/,pAjNv27)/. 39/,C3( 27 )/.008/,5 AN(27)/1.15/,C4(27),/0./,C5(27 )/O./,C(27)/23776000./,'6 D( 2 7 )/ 4 2 6 9 3 0 0 0./S5(27)/72513000./,GRUN(27)/1.16/,I Ql(27)/.2/,Q2(27)/4./,PMIN(27 )/10000000./,C9(27)/0./,8 Dl(27)/-.69/,D2(27),/2.39/,D3( 27)/-.50/,o4(27/, 004/,9 DS(27)/O. OO/,PFAXL(27)/860000./,EFMIN(27 )/.O36/,CIO(27)/0,/,A (DESCm(27,.7),J-1.,4) /4a*HY-,41,1130 ,4HSTEE,.4HL /B (DESCM(27,J),J..5,8) /4H ,4H ,4HRC-3,4H0 /C (DESCM(27,J),J-9,12)/4i ,4H ,4H ,4H /

FIGURE 24. DATA STATEMENTS FOR TII E PIC-2/EIPIC-3 MATERIA ILI1BRAIIY IN ENGLISH UNITS

36

NSWC TR 88-252

INPUT DATA FOR SOLID MATERIAL

MATERIAL NUMBER 25 *HY-80 STEEL RC-21

MASS/THERMAL PROPERTIESDENSITY w 0.725000E-03SPECIFIC HEAT 0 0.433000E+06CONDUCTIVITY 0.432000E+01VOLUME EXPANSION COEF 0.630000E-05INITIAL TEMPERATURE 0o.700000E+02ROOM TEMPERATURE 0.700000+02MELTING TEMPERATURE 0.276800E+04

STRENGTH PROPERTIESSHEAR MODULUS - 0.112400E+08YIELD STRESS, Cl - 0.974600E+05HARDENING COEF, C2 - 0.616400E+O5HARDENING EXPONENT, N - 0.360000E+00STRAIN RATE COEF, C3 - 0.140000E-01SOFTENING EXPONENT, M - 0.114000E+01PRESSURE COEF, C4 - 0.000000E+00MAX STRENGTH (OPTIONAL) O.OOOOOOE+00

EQUATION O' STATEEl - 0.237760E+08K2 - 0.426930E+08K3 - 0.725130E+08GRUNEISEN COEF - 0.116000E+01MAX NEGATIVE PRESSURE - 0.100000E+08

ARTIFICIAL VISCOSITYLINEAR COEF - 0.2000OOE.00QUADRATIC COEF - 0,400000E+01HOURGLASS COEF - 0.200000E-01

FRACTURE PROPERTIESDAMAGE COMPUTED - 0FRACTURE ALLOWED - 0Dl - -0.850000E+O00D2 - 0.270000E+01D3 - -0,500000E+00D4 - 0.600000E-02D5 - 04000000E+00MINIMUM FRACTURE STRAIN - 0.330000E-01SPALL STRENGTH 0.795000E+06STRAIN FOR TOTAL FAILURE - 0.999000E+03

EXTRA CONSTANTSX1 (C9) CERAMICS CRUSHED - 0.OOOOOOE+00X2 (Cl0) - O.OOOOOOE+00

FIGUIRE 25, EPIC-2/I'PIC-3 1IPREPROCESSOR OUTIPtITUFORI'TlE MATEi IAIL)ATA IN ENGLISII UNITS FOR IIY-80STI'XI,

37

NSWC TR 88-252



MASS/THERMAL PROPERTIESDENSITY 0.725000E-03SPECIFIC HEAT 0.433000E+06CONDUCTIVITY 0.432000Z+01VOLUME EXPANSION COEF 0.770000E-05INITIAL TEMPERATURE 0.700000E+02ROOM TEMPERATURE. 0.700000E+02MELTING TEMPERATURE 0.276800E+04

STRENGTH PROPERTIESSHEAR MODULUS 0.112400E+08YIELD STRESS, Cl 0.1099005+06HARDENING COEr, C2 0.583000E+05HARDENING EXPONENT, N 0.260000E+00STRAIN RATE COsF, C3 0.1100001-01SOFTENING EXPONENT, M 0.113000E+01PRESSURE COEr, C4 0.000000E+00MAX STRENGTH (OPTIONAL) 0,000000E+00

EQUATION OF STATEK1 - 0.237760E+08

2- 0.426930E+08K3 0.725130E+08GRUNCISEN COEr - 0.116000E+01MAX NEGATIVE PRESSURE 0.100000E+08

ARTIFICIAL VISCOSITYLINEAR COEF - 0.200000E+00QUADRATIC COEr - 0.400000E+01HOURGLASS COEF - 0.200000E-01

FRACTURE PROPERTIESDAMAGE COMPUTED 0FRACTURE ALLOWED 0D1 -0.610000E+00D2 0.207000E+01D3 ft -0.5OOOOos+00D4 w 0.100000E-01D5 w 0.OOOOOOE+00MINIMUM FRACTURE STRAIN - 0.340000E-01SPALL STRENGTH 0w819300E+06STRAIN FOR TOTAL FAILURE - 0.999000E+03

EXTRA CONSTANTSXl (C9) CERAMICS CRUSHED - 0.OOOOOOE+00X2 (C10) - 0.OOO E+00

FIGUR E 26. E PIC-2/,I IC-3 PREPROCESSOR OUTPUT FORITII•E MATERIALDATA IN ENGLISII UNITS FOR IIY-100 STEEL

38

NSWC TR 88-252



MASS/THERMAL PROPERTIESDENSITY - 0.738000E-03SPECIFIC HEAT - 0.422000E+06CONDUCTIVITY - 0.346000E+01VOLUME EXPANSION COEF - 0.730000E-05INITIAL TEMPERATURE - 0.700000E+02ROOM TEMPERATURE - 0.700000E+02MELTING TEMPERATURE - 0.276800E+04

STRENGTH PROPERTIESSHEAR MODULUS - 0.112400E+08YIELD STRESS, Cl - 0.133400E+06HARDENING COEF, C2 0.483000E+05HARDENING EXPONENT, N - 0.390000E+00STRAIN RATE COEF, C3 w 0.800000E-02SOFTENING EXPONENT, M - 0.115000E+01PRESSURE COEF, C4 - 0.000000+E00MAX STRENGTH (OPTIONAL) - 0.OOOOOOE+00

EQUATION OF STATEK1 - 0.237760E+08K2 - 0.426930E+08K3 - 0.725130E+08GRUNEISEN COEF w 0.11600054,01MAX NEGATIVE PRESSURE - 0.100000E+08

ARTIFICIAL VISCOSITYLINEAR COEF - 0.200000E+00QUADRATIC COEF - 0.400000E+01HOURGLASS COEF - Q.200000E-01

FRACTURE PROPERTIESDAMAGE COMPUTED 0FRACTURE ALLOWED 0Dlw -0.690000E+00D2 - 0.239000E+01D3 w -0.500000E+00D4 w 0.400000E-02ps w 0.0000005+00MINIMUM FRACTURE STRAIN w 0.360000E-01SPALL STRENGTH 0 0.860000E+06STRAIN FOR TOTAL FAILURE - 0.999000E+03

EXTRA CONSTANTSXI (C9) CERAMICS CRUSHED - 0.000000E+00X2 (C10) - 0.000000s+00

FIGURE 27. EP'IC-2IEP-IC-31 I'RE.I)IOCESSOR OUTIPUT 'FOR I I IE MATERIALIJATA IN INGLISh UNITS FOIl IIY-130 STEEiL

39/40

NSWC TR 88-252

SECTION 6

SUMMARY

HY-80, HY-100, and HY-130 steels have been tested at various strains, strainrates, temperatures and pressure. Th P .'2sults of these have been analyzed to obtainstrength and fracture constants for the corresponding models in the EPIC-2/EPIC-3codes. These constants have lBeen incorporated into the EPIC-2/EPIC-3 materialdata library.

41/42

NSWC TR 88-252

REFERENCES

1. Johnson, G.R. and Stryk, R.A., User Instructions for the EPIC-2 Code,AFATL-TR-86-51, Honeywell Inc., Defense Systems Division, Edina, MN,Sep 1986.

2. Johnson, G.R. and Stryk, R.A., User Instructions for the EPIC-3 Code,AFATL-TR-87-10, Honeywell Inc., Defense -ystems Division, BrooklynPark, MN, May 1987.

3. Alloy Digest, Published by Engineering Alloys Digest, Inc., Upper Montclair,NJ, Aug 1970.

4. Johnson, G.R., Hoegfeldt, J.M., Lindholm, U.S., and Nagy, A., "Response ofVarious Metals to Large Torsional Strains Over A Large Range of StrainRates - Part 1: Ductile Metals," ASME Journal of Engineering Materialsand Technology, Vol. 105, No. 1, San 1983, p. 4 2 .

5. Johnson, G.R., Hoegfeldt, J.M., Lindholm, U.S., and Nagy, A,, "Response ofVarious Metals to Large Torsional Strains Over a Large Range of StrainRates - Part 2: Less Ductile Metals," ASME Journal of Engineering Materialsand Technology, Vol 105, No. 1, Jan 1983, p. 48.

6. Mackenzie, A.C., Hancock, J.W., and Brown, D.K,, "On the Influence of StateStress on Ductile Failure Initiation in High Strength Steels," EngineeringFracture Mechanics, Vol. 9, 1977, p. 167.

7. Johnson, G.R., Development of Strength and Fracture Models for Computa-tions InvolvingSevere Dynamic LoadinM - Volume Strength and FractureMoes FT-R8-5 Honeywell Inc., Defense Syrstems Division, Edlina,MNiJan 1986.

8. Johnson, G.R. and Cook, W.H., "A Constitutive Model and Data for MetalsSubjected to Large Strains, High Strain Rates and High Temperatures,"Proceedings of Seventh International Symposium on Ballistics, The Hague, TheMth-eilands, Apr 1983.

9. Johnson, G.R. and Cook, W.H., "Fracture Characteristics of Three MetalsSubjected to Various Strains, Strain Rates, Tem peratures and Pressures,"Journal of Engineering Fracture Mechanics, Vol. 21, No. 1, 1985, p. 31.

10. Hancock, J.W. and Mackenzie, A.C., "On the Mechanism of Ductile Failure inHigh-Strength Steels Subjected to Multi-Axial Stress.-States," Journal of'Mechanics and Physics of Solids, Jun 1976, p. 147.

43

NSWC TR 88-252

REFERENCES (Cont.)

11. Nagtegaal, J.C., Parks, D.M., and Rice, J.R., "On Numericall y Accurate FiniteElement Solutions in Fully Plastic Range," Computer Methods in Mechanicsand Engineering, Vol. 4, 1974, p. 153.

44

NSWC TR 88-252

APPENDIX A

METALLURGICAL, RESULTS OF HY-80, HY-100,AND HY-130 STEEL

The metallugrical samples c iazh material were prepared in cross section forexamination in three planes using an antopolishing technique and etched with3 percent nital. The three oriental, ons examined were: a plane parallel to the platesurface and two planes 90' to pach other viewing the plate cross section. Variousdegrees of typical inclusions were noted in the fine tempered martensitic structures,The HY-130 (highexrtrength material) exhibited only spot, no linewr inclusions.Tyuical microstructures are illustrated: HY-80, Figures Al1 to A-5; HY-100,Figures A-6 to A-10; and HY-130, Figures A-Il to A-14.

A-1

NSWC TR 88-25 2

H oneyw~ell DEFENSE SYSTEMS DIVISIONMATERIALS AND PROCESS ENGINEERING 6014umif

VIEW AMAGNIFICATION: 200X

VILW 13MAGNIFICATION; 500X

PIGUMP L AB4 NUMM[IA M 6 PC ENOINUIlM& tTCH'INflV1iFIM1

A1 2478 .Domr Y-80 Steel

Photoniicroqr~i hs, of I-Y80 steel In cross s3ection at various an4li,'Icatiofl5 viewirij

__plano po'cciui o th san1c 1,ench. Vflewc A an] B 1i1t~stritc.typ)1ca'i

i ncl us ionspioci' ýto echig Etchaen 3% nital.

A-2

NSWC TI{ 88-252

Honeywell DAEFENSE SYSTEMS DIVISION EMATEIALSAND PROCESS ENGINEERING F4

MAGNIFICATION: 20OX

'~ VIEW 13is . . MAGNF ICAT iON: 50OX

AI3 T i A A.~r I' It .ý.:IMU-11 11 NJPN4IEtI

__Z7478 ____ ____ . D01 hnol I iy flY Steel

Miclostrucjturo phomiLr'uugroiphs of HY10 steel in cros,. ýuction at vm'icImrdjý, - nlfh

ations, viowing a plan., paidl lol to tho ý,afnplo loiwjth. Viowt; A A [A illuistrIto

typ)ic0f i nclu,.iofs lol lowinq ob1:Iin 1 .Ecat: 3ý4 n i U~ I__

T4PS37 Fltvq . . . . . . .- V- ___,-..- -

A -3

NSWC TR 88-252

Honeywell DEFENSE SYSTEMS DIVISION 7MATERIALS AND PROCESS.ENGINEERING

MAGIFICATO:20

MAGNIFICATION: 20OX

IC MI M' I A, UI1 y&'Ii~;',A ~ ~ CCWIAJ(M,(pC~_.UCJI

A 6

NSWC TP. 88-252

HoneywellDEFENSE SYSTEMS DIVISIONMATERIALS AND PROCESS ENGINEERING" r


41 MAGNIFICATION: 500X

0 1LI iM P A B N~UMU~t E 'E &iINWIl&' ~C~(CA jDCYICrjl Alit NU&MOL ft

A- 4 27478 ______ _______ .Dhnr JHY-80 Steel

flicrostr'ucturo photomicra:graphs of IIY60 steel in cross, soction at various

inagni Fications, vlewirg a plano paralleil to the sample longth. Views A a B

illustrate tempered mar-tersite. Etchan! ;3% nital. ___ _____ __

"*3 EV I _80

NSWC TR 88-252

HoneywellDEFENSE SYSTEMS DIVISIONMATERIALS AND PRiOCESS ENGINEERING


...... . . . . . AliVIEW BMAGNIFICATION: 50OX

OFIGPE m_&_'lLAD HUM BE 1 M 4 PL EN OINEER 1.P EHIIN MCI U 10

A5 27476 D, Dhnor HY--cO IteMicrostructuro photomnicrographs of IIY80 steel in C~ross section at various

magni ficat Ions, viewing a plane, porpendicular to the sample length. Viows A & B

illu~strate tempered martionsito. Etchant: 3l% nital.

IIP-532 REV liall

A-(6

NSWC TI{ 88-252

Honeywell DEFENSE SYSTEMS DIVISION r1 61

MATERIALS AND PROCESS ENGINEERING


VINW BMAGNIFICATION: 200X

I wunf.- 7m &-I,[ LAOJ NumutA &A O'f L NGINL 1 11 1A&I 11NOADV IIAI~A

LA-6 27476 B. L~hnr~ yOStee

Photomicrographs of HYlOB stesel in cro55 socti on, viewing a p] anu parallel to the

saniple long-th. Views A ý B illustrate all inclusion at tho 5urfdcu continuing

-irn the plato prior to otch ing. Etchant: 3% nital

A-7

NSWC TR 88-252

Honeywell DEFENSE SYSTEMS DIVISION IT R WdefT

MATERIALS AND PROCESS ENGINEEPING

VIEW AMAGNIFICATION: 20OX

VIEW B

MAGNIFICATION: SOOX

.IOUME M & 1t L AB NUMBII M & PC ENGINEER m & PE TECHNICIAN CVICE:IPAAI NUMBHE

A- 27478 j D. Dehmer HY-00 Steel

Microstructure ohotomicrographs of HY100 steel In cross section at various

magnf -ftons•_yi.gwiny a plane pdrallol to the sample length. Views A & B

ilhustr'a-I a line etching, Etcharnt: 3% nital.

HP-532 -[V 1I1R

A-8

N.SWC TR 88-252

Honeywell ~ DEFENSE SYSTEMS DIVISION HNfP

Hone wellMATERIALS AND PROCESS ENGINEERING


A-.WA

Mict-Osti-uctul'o photomnicrographs, of H1YIQO stecol In crosssect ion at varioujs

magnifications, Vil3wiFg ai planle parallel to U10 platO srfaco V 10ws A & 3

Illustrate tumpurad martunsito. Etchant: 3% nital, __

NSWC TR 88-252

HoneywellDEFENSE SYSTEMS DIVISION T

MATERIAL~S AND PR~OCESS. ENGINEERING


VILW~ MAGNIVICAIION: 500X

______0. - mer fly-]0 teMcrostructuro phatoniicrographs of HY1OG steel in cro5 o otna varloui3

inagitq~ifica-ioils, v-iowi ig ýi pladno -par-11o1 to tic. sampl lonagt oiw5 A& 1 3

Illus-trato tomporod rnartensito. E-tchant: 3% oftal.

A-10)

NSWC TR 88-252

Honeywell DEFENSE SYSTEMS DIVISIONMATERIALS AND PROCESS ENGINEERING I

MANFIAIN:20

VIEWA

MAGNIFICATION: 200X

.4'

1`U0iII 0"P CLA O NUMBF111& EN Nl M A. t(IITCNICIAN IE~FPR UI

A1iiL 2747 8 ____ D. Dohrnr IY10 teMicrosti ucturo photornlcroqrapiis of HYlOC Stnr 1 in cross section at v,,,rious

mdcjnlficdtions, viewingj a piano purpondic:Kor, to the sample length. Views A 0 [

illustrate tumpaord iar-tonsito, EtRInt: 3 nital.

,lI'7.]:lrV S tA -1 I

NSWC TR 88.252

Honey-well1 DEFENSE SYSTEMS DIVISIONMATERIALS AND PROCESS ENGINEERING 6014


i.|

MAGNIFICATION: 200X

LA NI4 J.PMOI~ln Pt ENGINEA . P( 1CHI~ CIAN DEYICMPA141 NUM HEll

A1780 Dehmor HY-130 S~teel

Photomicr'ographs of HY130 steel In cross section, vlowin a~p~anj~prallel to the.w A ---- '•us of - -hol_

z - -- 11r

--Lniu-qin-.pn .n.a ..rior to nt"1_ ing- r .,ju" inf!

A-12

NSWC TR 88-252

Honeywell DEFENSE SYSTEMS DIVISION EMATERIALS AND PROCESS ENGINEERING4


, ' 4:5',

MAGIFICATION: SOox

A1 24T ___ ______ I2 7478 IYiD Steed

Mict-ostructuro photornicrograph5. of !IYiJO steel in cros soto t various

magnifications, viewingj a piano parcillel to the plat ____(o Vlows A E 3

illustratoi tempeord martonsito. Etchant: 3% nital.__ _____

A - 13

NSWC TR 88-252

Honeywell DEFENSE SYSTEMS DIVISIONMATERIALS AND PROCESS ENGINEERING E ~~


VIEW Bvp:. MAGNIFICATION: 500X

FloJIHL M &PC LAU NUPOWtI FtI~ ENC NFUE t Er(CHNIIIAN DVClATNJQI

A-i13 27478 D. Dohrner w-3StlMicrostlru(tuire photomlcrographs of 1HYI30 steel in cross section dt var'ious~

magnilicationsp vinwing i plane parallel to the sample leng-th. Viow5 A & B

Illustrato tompered niartensito. rtchant, 3% nital.

A-14

NSWC TR 88-252

H n y elDEFENSE SYSTEMS DIVISION ETA MNUMUL4MATERIALS AND PROCESS ENGINEERING 61


.i MAGNIFICATION: 50OX

P IIUHE M Ph KLAH NUMBIN A 4 ' NIAEIPDvII ,~I JMI

A- 141 27/478 DHW1OSte

Microstl'UCtUr ploton Icro~jraph ofLNY130 steelI in cros 5oto t varfolls

mnajol tIcatlorns, Yiewio Dln iopnCllto .3'm(jL1~ývuý A & [3

illustratoi tlrnmiqod ThA t jmn -ý Ito L.UdiL;.i~Ili

A-15

NSWC TR 88-252

DISTRIBUTION

Copies CopiesChief of Naval Operations Commanding OfficerAttn: Technical Library 1 Naval Ordnance StationDepartment of the Navy Attn: Technical Library 1Washington, DC 20350 Indian Head, MD 20640

Office of Naval Technology Commanding OfficerAttn: OCNR-23 1 Naval Ship Weapons Systems

OCNR-232 1 Engineering StationOCNR-213 1 Port Hueneme, CA 93043

800 North Quincy StreetBallston Center Towers #1 Commanding OfficerRoom 503 Naval Undersea WarfareArlington, VA 22217-5000 Engineering Station

Keyport, WA §8345 1CommanderNaval Ocean Systems Center CommanderAttn: Technical Library 1 Naval Weapons EvaluationSan Diego, CA 92152 Facility

Kirtland Air Force BaseDefense Technical Information Albuquerque, NM 87117Center

Cameron Station CommanderAlextandria, VA 22314 2 Naval Underwater Systems

CenterOffice of Naval Research Attn: Technical LibraryAttn: Technical Library 1 Newport, RI 02840800 North Quincy StreetArlington, VA 22217 Director

# Defense Advanced ResearchSandia National Laboratories Projects AgencyAttn: Technical Library 1 Attn: LibraryAlbuquerque, NM 87185 Naval Technology Office 1

1400 Wilson BoulevardDirector Arlington, VA 22209Defense Nuclear AgencyAttn: Technical Library 1 CommanderWashington, DC 20305 Naval Weapons Center

Attn: Technical Library ICommanding Officer Code 3917 1Naval Coastal Systems Center China Lake, CA 93555Attn: Technical Library 1Panama City, FL 32407

(1)

S.. . .. In I I~ l I ' u l i a a ml m m _ l • l ~ m . . . •_ _ j • _ _i _. •

NSWC TR 88-252

DISTRIBUTION (Cont.)

Copies CoviesCommander Internal Distribution:Naval Air Systems Command E231 2Attn: Technical Library 1 E232 3Washington, DC 20361 R 1

R10 1Commander R10A 1U.S. Army Research and R10A (K. Reed) 1

Development Command RI2 1Attn: Technical Library 1 R12 (P. Walter) 2Dover, NJ 07801 R13 1

R13 (F. Zerilli) 2Commander U 1Air Force Weapons LaboratoryAttn: Technical Library (SUL) 1Kirtland AFB, NM 87117

Commanding OfficerHarry Diamond LaboratoriesAttn: Library 12800 Powder Mill RoadAdelphi, MD 20783

DirectorDefense Research and

EngineeringAttn: Library 1Washington, DC 20305

Lawrence Livermore NationalLaboratory

Attn: Technical Library 1Livermore, CA 94550

Los Alamos National LaboratoryAttn: Technical Library 1P.O. Box 1663Los Alamos, NM 87544

(2)

dtic - defense technical information center tr 88-252 illustrations figgre pg 1 stress-strain data...

Documents