'I ILE -C0PN

MTL TR 88-36 AD

EVALUATION OF SOLID LUBRICANTS:TEMPERATURE PROGRAMMED DESORPTIONOF MoS2 ON MOLYBDENUM AND OF

ION-IMPLANTED MoS2 ON MOLYBDENUM

RICHARD P. BURNS and DANIEL E. PIERCE0 UNIVERSITY OF ILLINOIS AT CHICAGO

HELEN M. DAUPLAISE, KENNETH A. GABRIEL,and LAWRENCE J. MIZERKAMATERIALS SCIENCE BRANCH

November 1988

DTIC• ELECTE

Approved for public release; distribution unlimited. 3 0 J A N 1989 D÷E

LABORATORY COMMAND U.S. ARMY MATERIALS TECHNOLOGY LABORATORYMTAEMI t•UWMo LUOMToW Watertown, Massachusetts 02172-0001

89 1 27 051

The findings in this report are not to be construed as an official

Department of the Army position, unless so designated by otherauthorized documents.

Mention of any trade names or manufacturers in this reportshall not be construed as advertising nor as an officialindorsement or approval of suzh products or companies by

the U-ited States Government

DISPOSITION INSTRUCTIONS

Destroy this report when it is no longer needed.Do not return it to the originator.

UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS PAGE ("oen Date Entered)

REPORT DOCUMENTATION PAGE READ INSTRUCTIONSBEFORE COMPLETING FORM

I REPORT NUMBER 2 GOVT ACCESSION NO. 3 RECIPIENT'S CATALOG NUMBER

MTL TR 88-36

4 TITLE (and Subtitle) 5 TYPE OF REPORT & PERIOD COVERED

EVALUATION OF SOLID LUBRICANTS: TEMPERATURE Final ReportPROGRAMMED DESORPTION OF MoS 2 ON MOLYBDENUM ANDOF ION-IMPLANTED MoS 2 ON MOLYBDENUM 6 PER(ORM.NG ORG REPORT NUMBER

7 AUTHOR(s) 8 CONTRACT OR GRANT NUMF3ER(s)

Richard P. Burns,* Daniel E. Pierce,*Helen M. Dauplaise, Kenneth A., Gabriel, and DAALO4-86-K-0003Lawrence J. Mizerka

9 PERFORMING ORGANIZATION NAME AND ADDRESS ,0 PROGRAM ELEMENT. PROJECT, TASKAREA & WORK UNIT NUMBERSU.S. Army Materials Technology Laboratory D/A Project: IL16110IA91AW.atertown, Massachusetts 02172-0001 AMCMS Code: 611101.91A0011

SLCMTEMS Agency Accession:DA308489

II CONTROLLING OFFICE NAME AND ADDRESS 12 REPORT DATE

U.S. Army Laboratory Command November 19882800 Powder Mill Road 13 NUMBER OF PAGES

Adelphi, Maryland 20783-1145 2414 MONITORING AGENCY NAME & ADDRESS(il different from Controlling Office) 15 SECURITY CLASS (of this report)

Uncl assifiedISa DECLASSIFICATION'DOWNGRADING

SCHEDULE

16 DISTRIBUTION STATEMENT (of this Report,

Approved for public release; distribution unlimited.

17 DISTRIBUTION STATEMENT (of the abstract en•teed in BloOk 20. ii different from Report)

18 SUPPLEMENTARY NOTES

*Department of Chemistry, University of Illinois at Chicago.

19 KEY WORDS (Continue on reverse vide itf ncessarý and identify by block number)

Solid lubricants/ Surface analysis X-ray photoelectron/ Molybdenum disulfide Thermal degradation spectroscopy J-'-

Mass spectrometry Thermal stability

20 ABSTRACT (Continue on reverse side if necesaarl and identify by block number)

(SEE REVERSE SIDE)

DO IoJm 1473 EDITION OF 1 NOV 65 IS OBSOLETEN SR CS73 UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS PAGE (When Date E'nter-ed)

UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS *G•E ftWhn Od41 Fned)

Block No. 20

ABSTRACT

Thermal programmed desorption (TPD) is utilized in order to assess the lubri-cating properties of metal dichalcogenide films applied to a number of metal sub-strates. TPD spectra documenting desorption and decomposition products wereanalyzed for MoS 2 burnished on mclybdenum metal with and without subsequent 86 kVnitrogen ion implantation. Desorption order, rate, energy, and the pre-exponential of evolved lubricant and nitrogen species from the molybdenum bub-strates were determined. The surface chemistry of heated lubricant-substratesystem was investigated by means of X-ray photoelectron spectroscopy (XPS).' Theresults presented clearly indicate that the mass spectroscopic TPD techniquesdeveloped for this investigation coupled with careful surface analysis yieldcritical in situ assessment of the capability and the operational limits of thisand other solid lubrication systems,

:./

UNCLASSIFIEDSECURITY CLASSIFIC TION or THIS PAGe W% Orae Fed

CONTENTS

Page

INTRODUCTION .. ................. .. .......... I

EXPERIMENTAL. ... ................... 2

RESULTS

Electron Micrographs ...... ................. 4

MoS 2 Coated Non-Implanted (C), ................ 4

XPS Spectra ..... .......... ........... 6

MoS 2 Coated, Ion-Implanted Metal (CI) .... ...... 6

DISCUSSION ....... ... ....................... 8

CONCLUSIONS .. . . . . . . . . . . . ..... . . . . 9

ACKNOWLEDGMENTS 10........................... 10

REFERENCES ........................ .21

Accr,:slon 1orNýT IS: GY ;,A

LTIC T&,• S

Ci U m:'nour:ce' m

Availabi!•tv Codes

jAvali andc/or

it Special

INTRODUCTION

The need for advanced materials for use in either high temperature and/or high

vacuum and space environments have recently promoted significant research and

development efforts 1-7 in the area of solid lubrication technology. Although several

metals, metal oxides, metal halides, metal sulfides, metal selenides, and other compounds

and mixtures of compounds have been shown to exhibit good solid lubrication

properties, metal dichalcogenides in general and molybdenum disulfide 8-10 in

particular have emerged as the most promising candidates for solid lubrication in a

number of important vacuum and space applications.

The structure of MoS 2,11 shown in Figure 1, is characterized by a layer config-

uration which consists of a hexagonal layer of Mo atoms sandwiched between two planes

of hexagonal sulfur atoms. The atoms are arranged so that the sulfur planes are

staggered with respect to the plane of metal atoms allowing each Mo atom to be placed at

the center of a trigonal prism formed by the surroundi!,g ,ix sulfur atoms. A con-

sequence of this structure is that relatively weak forces between the sulfur-sulfur planes

account for the excellent lubricating properties similar to those of graphite and other

similar layered structures.

The deleterious effects of environmental conditions on the performance of these

materials are two critical engineering parameters which have been examined by several

tribologists 12-14 in order to optimize these compound's lubricity for specified

application conditions. In this work we utilize the method of thermal programmed

desorption (and/or decomposition) (TPD) to determine the desorption and/or

decomposition kinetics of burnished and nitrogen ion- beam mixed MoS2 films on

molybdenum.

Thermal programmed desorption 15-17 is a technique in which the temperature of an

adsorbed film or coating on a surface of interest is raised from an ambient or low

temperature in a programmed manner, usually linearly with time, and the resulting

desorbed, evaporated, or decomposed species are monitored and recorded by a suitabledetector, usually a mass spectrometer. This process yields a spectrum of the rate of

evolutior 1 various species from the surface as a function of surface temperature.Analysi, ,f sets of 4TPD spectra yield kinetic information on the bonding of the film orcoating to the surface, as well as provide insight into the processes occurring at thesurface and leading to the evolution of the evaporated species.

The present work was undertaken in order to assess the usefulness of the TPDtechnique in the analysis of the high temperature degradation mechanisms of lubricatingmetal dichalcogenide films applied to various systems. A better understanding of suchdegradation mechanisms can lead to the development of improved preparationtechniques, improved application techniques, and also the development of surfacemodification techniques capable of blocking particular degradation pathways.

In this report of phase one activity, results on the modification of a MoS 2 film by ion

implintation are also presented. Ion implantation can introduce high energy, metastablestates into the metal-fi'lm systems and in principle the presence of these metastable statescan modify the properties of the lubricating film-metal system.

This phase of our effort focuses on the effect of temperature not only as a degradativeprocess, but also as a diagnostic tool for investigating solid lubricant systems. Inparticular, TPD spectra are presented for: molybdenum metal; ion- implantedmolybdenum metal; ion-implanted MoS 2 coated molybdenum metal; and MoS 2 coated

molybdenum metal which was not ion implanted, but the MoS2 was applied by various

burnishing techniques.

EXPERIMENTAL

The TPD evaluation system shown in simplified form in Figure 2 has been developedin order to study the gaseous species evaporating at elevated temperatures from solidlubricant coated surfaces. It consists of a pumping chamber which includes a 400 I/s ionpump and a titanium sublimation pump and an experimental chamber separated from thepump by a gate valve. After baking overnight at 370 K, the base pressure was in the low10-9 Torr range. The sample holder conveniently held three samples but could be usedto hold several more. Each sample was positioned so that when heated the gaseous

2

species evaporating from the surface could enter the mass spectrometer ionizer by a line

of sight path. The mass spectrometer is a Finnagan Model 1015 quadrupole mass

spectrometer modified for molecular beam studies. Mass and transmission calibration

was performed by introducing perfluorotributylamine which has a known

fragmentation pattern.

Finely ground crystals of MoS 2 were applied to clean etched 0.002-inch-thick

molybdenum metal foils. The lubricants were burnished onto a defined area of one side

of the foil with a paper lab wipe, a nylon wiper, or a clean tantalum foil. About 100

micrograms cm-2 MoS 2 adhered to the paper-rubbed metal surface as determined with a

Cahn RH electrobalance. This amount of MoS 2 constitutes a coating containing 375

layers or 2300 A thick. Chemical analysis indicates that the MoS 2 powder used in this

investigation contains between 1.6 and 1.9% carbon (depending on the sample) and less

than 0.3% oxygen for all samples. The amount of carbon impurity is equivalent to one

carbon for every 3.8 to 4.6 formula units of MoS2.

The coated foils were attached to specially designed holders. These holders enabled

resistive heating of the metal foil to temperatures higher than 2000 K. A calibrated 3%

Re/W-25% Re/W thermocouple pair was spot welded to the back of the sample for

temperature measurement. The thermocouple signal was compared to a referencevoltage and the difference was used to control the output of the heater power supply..The reference voltage was programmable and was adjusted to give a ramp rate of 7.5

degrees sec1

A Teknivent Model 1050 mass spectrometer data system controlled the quadrupole,

recorded ion currents and temperature, and initiated the heating of the sample.Experiments were first undertaken to survey the entire mass spectrum as the sample

temperature was ramped. Next, the experiment was repeated and only those massesindicated by the survey were recorded, greatly increasing the signal to noise ratio. Thelowest mass monitored was carbon at 12 amu. The high mass limit of the quadrupolewas about 750 amu and this allowed the gaseous molybdenum oxide species (MO0 3)x,

(x = 1, 2, 3, 4) to be monitored.

3

X-ray photoelectron spectra (XPS) were taken for coated foil samples in both thesurvey and high resolution mode. The MTL Leybold-Hereaus LHS- 12 Surface AnalysisSystem was used to obtain these spectra. It includes a hemispherical electron energyanalyzer, Mg and Al X-ray anodes, and a heated probe capable of heating samples to950 K.

Some of the coated foils were ion-beam modified with nitrogen ions. Theimplantation was performed with the MTL Zymet system. An 86 keV ion beamconsisting of nitrogen ions (N+ and 10% N2+) was used. A 4 ma beam current wasmaintained for 92 minutes giving a total dose of 2 x 10+17 ions cm2 . Foil samples wereattached to an aluminum plate, and during the implantation the temperature which wasmeasured with a thermocouple reached 177 *C ± 17 *C.

A JEOL JSM-35C scanning electron microscope was used to study the physicalappearance of the metal surface and the MoS2 coated metal surface before and after ionimplantation.

RESULTS

Electron Micrographs

A comparison of Figures 3 and 4 illustrates the smoothing and compacting effect ofburnishing the MoS 2 crystals. From Figures 5 and 6, the surface modification caused bythe ion implantation of molybdenum can be seen. A comparison of Figure,- 4 and 7demonstrates the dramatic effect of the ion implantation process on the MoS 2 coating.Figures 8 and 9 show tlis dramatic effect at higher magnification, and clearly indicate

surface reconstruction.

MoS 2 Coated Non-Implanted(C)

The decomposition of the coating starts as low as approximately 565 K (292 °C).This low temperature decomposition results in SO2 vaporization. At highertemperatures both S2 and CS 2 vaporize.

4

1. Low Temperature Mass 64 Peak (see Figure 10) - Though both S2 and SO 2

molecules have masses of 64, the isotope ratio between mass 64 and mass 66 indicates

SO2 instead of S2. The maximum rate of vaporization occurs near 700 K. The p. ak

shape suggests second order kinetics with an activation energy for vaporization of 19kcal mo 1-1 and a pre-exponential factor of 1 x 10-10.

2. High Temperature Mass 64 Peak (see Figure 10) - Based on the isotope ratio andfragmentation pattern, this peak was found to represent vaporization of S2 molecules.

This mass 64 peak represents a major fraction of the total volatile sulfur species formedduring coating decomposition. The peak begins at about 1140 K and reaches a maximumrate of vaporization at 1465 K. The peak shape indicates first order kinetics, with anactivation energy of 81 kcal mo1- 1 and a pre-exponential factor of 5 x 1011.

3. High Temperature Mass 76 Peak (see Figure 10) - The peak at mass 76 representsvaporization of CS2 molecules. This peak is comparable in size to the mass 64 peak, but

is more complex. Both the mass 64 and mass 76 peaks have their maximum rate ofvaporization at 1465 K. In the area immediately surrounding this temperature, the mass

76 peak has nearly the same shape as the 64 peak. Features indicating smaller peaksbegin to appear at about 150 degrees on either side of the main mass 76 peak. Analysisof the main peak indicates first order kinetics with an activation energy of 80 kcal mo 1-

and a pre-exponential factor of 2 x 1011.

4. The Effect of Burnishing on the Mass 76 Peak (See Figure 11) - Clean Ta metalwhich is not a source of carbon shows one main peak with a low temperature shoulder in

the bottom panel of Figure 11. This low temperature peak is seen in the spectra for boththe nylon and paper-rubbed samples. Paper rubbing induces a substantial hightemperature CS 2 state as shown in the top panel of Figure 11. The nylon-rubbed sampleshows peak broadening due to the presence of these two additional states as indicated in

the middle panel of Figure 11.

5. Evidence for Interaction of H2O with the MoS 2 Coating (see Figure 12) - The top

panel of Figure 12 shows the simultaneous production of H20 and SO2. It is well known

that water oxidizes MoS2 and causes degradation of lubrication properties 14

5

6. Other Sulfur Species (See Figure 12) - Elemental sulfur v-'porizes to variouspolymers (S8, S6,...). The MoS 2 coating vaporizes primarily as S2, however some S4

is observed as illustrated in the bottom panel of Figure 12.

XPS Spectra

Recent enhancements to the MTL Leybold-Heraeus LHS-12 Surface Analysis Systemhave enabled the acquisition of XPS spectra before and after heating the MoS2/Mo

sample to 450 'C. Figure. 13 shows an XPS survey spectrum which was taken beforeany surface treatment, including heating, took place. Figure 14 shows the molybdenum3d peaks before heating. The peak at 228.9 eV is interpreted as one of a pair of Mo 3d(IV) peaks. The peak at 232.1 is interpreted as the sum of Mo 3d(VI) and the Mo3d(IV) lines. The peak at 235 eV is interpreted as one member of a pair of Mo 3d(VI)peaks. Based on these assumptions, a synthesized Mo 3d spectrum based on MoS 2,

M0O 2, and MoO 3 is shown in Figure 14 along with the experimental points. The

agreement is satisfactory.

Figure 15 shows a survey spectrum of the MoS 2 surface after heating to 450 'C. It

should be noted that this temperature is high enough to desorb the water and SO 2.

Figure 16 shows the Mo 3d peaks after heating. Note that the peak at 235 eV is nowmissing and the Mo 3d peak pair ratio more nearly corresponds to that for MoS 2.

Figure 16 also shows a synthesized Mo 3d spectrum based on MoS 2 and MoO 2 along

with the experimental points obtained after heating. The agreement is satisfactory.

MoS 2 Coated, Ion-Implanted Metal (CI)

The decomposition of the coated ion-implanted sample (CI) is distinctly differentfrom that of the coated, non-implanted (C) sample. There is a marked reduction in the

SO2 peak, and the S2 and CS2 peaks are shifted to lower temperatures. The nitrogenimplantation of molybdenum metal and MoS 2 coated molybdenum metal resulted in

nitrogen vaporization as monitored at mass 14.

6

1. Low Temperature SO 2 Peak (see Figure 17) - This peak with a maximum in the

700 K region is due to S02 vaporization. The relative magnitude of the ion-implanted

SO 2 peak is greatly reduced compared to the non ion-implanted sample. Figure 17 shows

a comparison between the SO2 and H20 peaks.

2. High Temperature S2 and CS2 Peaks (see Figure 18) - The top panel in Figure 18

shows that the major mass 64 peak due to S2 vaporization occurs at 1378 K. This is 87

degrees lower than the major peak of the coated non-implanted sample. On the lowtemperature side of the 1378 K peak, a smaller unresolved peak has been produced.

The mass 76 spectrum shown in the lower panel of Figure 18, due to CS2

vaporization, is characterized by a combination of at least three peaks. The only

resolved peak is the largest one which is found at 1378 K, precisely the same

temperature as the major S2 peak. As in the case of the 64 peak, on the low temperature

side, there exists a smaller unresolved peak. On the high side of the CS2 peak, slow

tailing suggests another small unresolved peak.

3. Nitrogen Mass 14 Peak (see Figure 19) - The nitrogen vaporization from

molybdenum metal and from MoS 2 coated molybdenum metal is shown in the top panel

of Figure 19. In both cases the spectra show that the nitrogen is released from discrete

states. For the metal alone, a large peak at 1248 K and a small peak at 1413 K are

observed. For the coated sample the main peak occurs at 1428 K. It may be noted thatthe presence of the coating has caused a 180 degree increase in the nitrogen release

temperature.

The lower panel of Figure 19 shows that a large fraction of the sulfur is releasedbefore the nitrogen release reaches its maximum. One may also note the simultaneousrelease of nitrogen and sulfur for the minor states occurring at approximately 1050 K.

7

DISCUSSION

1. The Low Temperature SO2 Peak (see Figures 10, 12, and 17) - The lowtemperature S02 peak shown in Figures 10, 12, and 17 arises from a desorption processwhich obeys second order kinetics and appears to be related to the presence of water.Since the Mo 3d XPS spectrum indicates that some of the Mo(IV) was oxidized toMo(VI) on the surface, one possible mechanism for the production of SO 2 may involve

the reaction between the MoS 2 and oxygen containing species. The area of the lowtemperature S02 TPD peak is 20 % of the area of the high temperature S2 peak as shownin Figure 10. This comparison indicates that SO 2 production can lbe an important

pathway leq .kiiig to lubricant failure. In contrast, Figure 17 shows that ion implantationhas reduced the low temperature SO2 peak by more than a factor of 10. Therefore, theimportance of this pathway to lubricant failure may also be reduced by ion implantationof the lubricant.

2. The High Temperature Sulfur Peak - Figure 10 summarizes the TPD results forthe MoS 2 film on molybdenum metal (with no ion implantation). The dominant feature

shown in Figure 10 is the first order S2 peak. This S2 peak arises from the thermaldecomposition of the MoS2 film. The decomposition process starts at 1140 K andreaches a maximum rate at 1465 K. Clearly, the onset of decomposition sets an uppertemperature limit for long term lubrication applications.

Figure 7 shows that the onset of CS2 vaporization starts at 1128 K and reaches a

maximum at 1465 K. The main part of this CS2 peak is similar in shape to the first order

S2 peak. This similarity suggests that both S2 and CS2 share a common rate determiningprocess in their formation. The CS2 peak is roughly equal in area to that of the S2 peak.This suggests that a large carbon impurity is present in the film-metal system. The XPSspectra andelemental analysis confirm the presence of carbon as an impurity in theMoS 2.

Figure 18 summarizes the TPD results for the ion implanted molybdenum metal-MoS2 film system. The main S2 and CS2 peaks are shifted to lower temperatures by

8

87 degrees. Figure 18 also shows that ion implantation dramatically reduces the thermalstability of the MoS 2 coating, because the film vaporization rate is increased for

temperatures between 1150 and 1350 K.

The lower panel of Figure 19 shows that ion implantation has induced a minor peak at1048 K. Figure 19 also indicates that there is a corresponding minor nitrogen peak at

the same temperature.

3. The Nitrogen Peaks - The TPD spectrum for ion-implanted bare metal is shownin Figure 19. This spectrum is characterized by one major peak at 1248 K and oneminor peak at 1413 K. These peaks may arise from nitrogen trapped in metal defectsites such as interstitials or vacancies. The interpretation of these peaks as originatingfrom a nitride phase(s) is being considered.

Figure 19 shows that the main nitrogen peak for the ion-implanted MoS 2 coated

system is shifted to a higher temperature by 180 degrees. There remains a small peak at1258 K which may result from the same state of nitrogen observed at 1248 K fornitrogen implanted bare metal.

It is worth noting that the presence of the MoS 2 coating changes the main nitrogenpeak to a higher temperature state. This shift to a higher energy state could result inimproved system performance. At this time, the mechanism for the preferential fillingof the high energy state is unclear, but this should be investigated in the future.

CONCLUSIONS

The results presented in this phase one report clearly indicate that the massspectrometric TPD techniques developed for this investigation can produce a wealth ofnew information about the thermal and chemical stability of thin solid lubricant films.In particular, TPD is sensitive to the film burnishing technique, as well as to the effect ofion-implantation. These results strongly suggest the TPD may coritribute to ourunderstanding of the thermal and chemical stability of thin films applied by othertechniques such as sputtering and ion plating.

9

In the future, we hope to continue our joint program and to use our combined TPD

and XPS techniques to better understand various properties of coating systems of

importance to selected Army missions.

ACKNOWLEDGMENTS

We wish to thank the staff of UIC for their contribution to this effort. In particular,

we acknowledge the efforts of Don Rippon, Paul Michaud, and John Costa. In addition,we acknowledge the expert photographic laboratory services donated by Mr. Desmond

Pierce.

We also wish to thank the staff of MTL for their help with this program. Inparticular, we appreciate the efforts of Dr. Ed Johnson and Mr. Forrest Bums in ionimplanting the samples for this investigation. Our appreciation is also extended toDr. James Marzik for helpful discussion and comments, as well as to Ms. Marion Gould

for her skilled assistance in preparing this report for publication.

Finally, we wish to thank Dr. James McCauley for his encouragement, insight, andsupport.

10

I I g I

co--122• A - Jn I • .__ Figure 1. Crystal structure of molybdenum disulfide.

-- ao,3.16 A *t-,o Os

Sample Manipulator

To

r-~r--- ~ Ion

N, Pump

Molecule Ionizer ,\\ *,

Figure 2. System for th. evaluation of the thermal andj 'chemical stability of solid lubricants.

*-

"-Coated Sample/~~~ ~ ,/- T= T(t)

/ \

/ / Molecular Beam Flag

LObservation /vacuum ýQuadrupoleWIndows Chamber Mass Spectrometer

11

10.0 t

Figure 3. MoS2 powder (25 kV, Mag. 2000X).

%*

12

10.0p

Figure 5. Molybdenum metal (M) (25 kV, Mag. 2000X).

10.0 ~

Figure 6. ion-implanted molybdenum metai OjM) 1,25 LzV, Maq. 20OOX).,

13

10.0 /i

Figure 7. Ion-implanted MoS2/Mo (1CMV) (25 kV, Mag. 2000X).

41

1.0/

Figure 9. Ion-implanted MoS2 /Mo (ICM) (25 kV, Mag. 1O,O0OX).

15

CS2

502 S

500 1i0 1O00 t250 1500 1750 2000

Temperature (K)

Figure 10. Intensity (desorption rate) of SO 2 , S2, and CS2 as afunction of temperature for MoS 2 (burnished)/Mo (CM).

PaperRubbed

r- /

NylonRubted(lightly)

TantalumRubbed

1000 1100 1200 1300 1400 1500 t600 t700 1800 1900

Temperature (K)

Figure 11. Intensity (desorption rate) of CS 2 as a function of temperaturefor MoS 2 (burnished)/Mo (CM) for different burnishing techniques.

16

H2 0 (xD)

S02(xW)

-*00 45". 500 550 600 650 700 750 800 850 900 950 1000

S100j_c S75

50

25 5

1100 H150 1200 t250 1300 13.C i40 1450 1500 1550 1600 1650 1700 1750 1800

Temperature (K)

Figure 12. Top -- intensity (desorption rate) of H2 0 and SO 2as a function of temperature for MoS 2 (burnished)/Mo (CM);bottom - intensity (desorption rate) of S2 and S4 as a func-tion of temperature for MoS 2 (burnished)/Mo (CM).

#Nointensity

+M400 (3P)

n 90

70

50

40- (2p)

* Au20 Ho ( 4p)

800 800 400 200 0bind. energy CeVJ I In

Figure 13. XPS survey spectrum for MoS 9 /Mo (CM) before heating.

17

Intensity

lun ____.__ ___

40-

2GD

10

235 234 232 230 228 225bind. energy EeV] uIn

Figure 14. Synthesized Mo 3d spectrum (solid line) and the experimentalMo 3d spectrum (points) before heating.

*M~o (d3dIntanenity

lin 9 #4o (3 pi)

*No (3p3)

0 0 (1e)

70-

50-

50- 0 OKLL)

40-* S (2p)

30-

No0 (4p)20

000 tiO 40ý0 206 0bind. energy [EV] Itn

Figure 15. XPS survey spectrum for MoS 2 /Mo (CM) after heating to 4500 C.

18

Intensity

lin

70--

.D --

a0i-

30- __

- - -

jn I

238 235 234 233 232 231 230 229 220bind, energy CeV3 1un

Figure 16. Synthesized Mo 3d Spectrum (solid line) and the experimental Mo 3d spectrum (points)after heating to 4500 C.

H20 MoS2 (burnished)/Mo +

N+ (86 kV)

S 0so2(xS5)

. .." l... ... ...... .. i. .. I. . i. . !. . I. .

400 450 500 550 600 650 700 750 000 850 900 950 1000

Temperature WK

Figure 17. Intensity (desorption rate) of H2 0 and SO 2 as a function

of temperature for ion-implanted MoS 2/Mo (CICM).

19

• m • • wmmw n m w •m • m w w w • mM

S2

tool Implanted Non-implanted

750501 M NkS2(burnishedllMo +

N+ (86 MV

25. 7

0 ~...................... ...... I

S1100 1150 1200 1250 1300 1350 1400 1450 1500 1550 1600 1650 1700 1750 1800Figure 18. Thp - changes in the S2 release due to ion

2100- Ipneimplantation for the MoS 2 /Mo system;, bottom ý changesoin the 0S2 release due to ion implantation for the

S Implanted Non-implanted MoS 2 /Mo system.

50 MoS2 (burnished)/Mo +N+(86 MV

25

1100 1150 1200 1250 1300 1350 1400 1450 1500 1550 1600 1650 1700 1750 1800

Temperature (K)

100" N+75] '

Mo +N+ (86 kV) NMoS21Mo + N+ (86 kV)

:• 0t ......~~~~ ~~~... ......'":"','r',...........'."..".-..'.....".....r",'',","'

800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000Figure 19.. Top - comparison of the nitrogen release from

N+ implanted metal (IM) and from MoS 2 /Mo (ICM);,- 1001 4 bottom - comparison of the S2 release with the nitrogen

+ S +S2 N+ release for N implanted MoS 2 /Mo (OCM).E 75]

21SMID0 ;. MoS2(burnished)/Mo +50 +

25 ~N+ (86 WV25,

01 7 ... . ...... .T..r.I

800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Temperature (K)

20

REFERENCES

I. BUCKLEY, D. H. Friction and Wear of Ceramics. Amer, Cer. Soc. Bull., v. 51,1972, p, 884.

2. LINCE, J, R., and FLEISCHAUER, P. D. Summary Abstract: Noble Gas IonBombardment of the Basal Plane Surface of MoS 2 . J3 vac, Sci, Tech. A, v. 5,1986, p. 1312.

3. KANAKIA, M. D., PETERSON, M. B, Literature Review of Solid LubricationMechanisms. Defense Technical Information Center, AD A185010, Alexandria, VA,1986,

4. KOBS, K., DIMIGEN, H., HUBSCH, H., TOLLE, H. J., LEUTENECKER, R., and RYSSEL, H.Improved Tribological Properties of Sputtered MoSX Films by Ion Beam Mixing.Appl, Phys. Lett., v. 49, 1986, p. 496..

5. McCONNELL, B., D., SNYDER, C. E., and STRANG, J. R. Analytical evaluation ofGraphite Fluoride and Its Lubrication Performance Under Heavy Loads. Lubr. Eng.,v, 33, 1977, p. 184,

6, SLINEY, H. E. Solid Lubricant Materials for High Temperatures - A Review. Tribol.Int., v. 15, 1982, p. 303.

7. SPALVINS, T. J. A Review of Recent Advances in Solid Film Lubrication, J. Vac.Sci. Tech. A, v. 5, 1987, p. 212.

8. LINCE, J. R., CARRE, D. J., and FLEISCHAUER, P.. D. Effects of Argon IonBombardment on the Basal Plane Surface of MoS 2 . Langmuir, v, 2, 1986, p, 805.

9. STUPP, B. C. Synergistic Effects of Metals Co-Sputtered with MoS 2 . Thin SolicFilms, v, 84, 1982, p. 257.

10. SUZUKI, K., SOMA, M., ONISHI, T., and TAMARU, K. Reactivity of MolybdenumDisulfide Surfaces Studied by XPS. J, Electr. Spect. Relat, Phen., v. 24,1981, p. 283.

11. WYCKOFF. R. W, G. Crystal Structures, v. I, Chapter IV, Interscience Publishers,NY, 1957.

12. FLEISCHAUER, P. D. Effects of Crystallite Orientation on Environmental Stabilityand Lubrication Properties of Sputtered MoS 2 Thin Films. ASLE frans., v. 27,1983, p. 82,

13. STEWART, T. B., and FLEISCHAUER, P. D. Chemistry of Sputtered Molybdenum DisulfideFilms !inorg. Chem.., v. 21, 1982, p. 2426,

14.. ROBERTS, E. W. The Tribology of Sputtered Molybdenum Disulphide Films. Proc. I,Mech., Eng., v. 1, 1987, p. 503ý

15. CHAN, C, M., ARIS, R., and WEINBERG, W. H.. An Analysis of Thermal DesorptionMass Spectra.I. Appl. Sur. Sci., v. 1, 1978, p. 360.

16. HABENSCHADEN, E., and KUPPERS; J. Evaluation of Flash Desorption Spectra. Sur.sci,, v. 138, 1984, p. L147.

17. FALCONER, j. L,, and SCHWARTZ, J. A, Temperature-Programmed Desorption andReaction: Applicationa to S2upported Catalyst~s.Catal. Rev.-Sci. Eng.,•. 5,1983, p. 141.

2,

DISTRIBUTION LIST

No. of No. ofCopies ro Copies To

Office of the Under Secretary of Defense for PFsearch and Commander,. U.S. Army Missile Cvrinand,, Redstone ScientificEngineering, The Pentagon, Washington,, DC 20301 Information Center, Redstone Arsenal,, AL 35898-5241

1 ATTN. Mr. J. Persh 1 ATTN, AMSMI-RD-CS-R/ILL Open Lit1 Dr. L. Young 1 AMSMI-R, Dr. W. C McCorkleI Mr. K. R. Foster

Commander, U.S. Army Aviation Systems Command, P.O. Box 209Commander, U.S. Army Laboiatory Command, 2800 Powder St Louis, MO 63120Mill Road, Adelphi, MID 20783-1145 1 ATTN* AMSAV-NS, Mr. M. L. Bauccio

2 ATTN, AMSLC-IM-TL Technical LibraryI AMSLC-TD1 AMSLC-TD-A Commander, U.S. Army Natick Research, Development, and1 AMSLC-PA Engineering Center, Natick, MA 017601 AMSLC-TP I ATTN. Technical Library

1 Dr. J. A. SousaCommander, Defense Technical Information -enter, Lameroni 1 Or. R. J. ByrneStation, Building 5, 5010 Duke Street, A'exardria, 1 Dr. R. LewisVA 22304-6145

2 ATTN. DTIC-FDAC Commander, U.S Army Satellite Communications Agency,Fort Monmouth,, NJ 07703

1 National Technical Information Service, 5285 Port Royal I ATTN. Technical Document CenterRoad, Springfield,, VA 22161

Commander, U.S. Army Science and Technology CenterDirector, Defense Advanced Research Projects Agency, Far East Office, APO San Francisco,, CA 963281400 Wilson Boulevard, Arlington,. VA 22209 1 ATTN' Terry L. McAfee

I ATTN, Dr. P. Parrish1 Dr. B. Wilcox Commnnder,, U.S. Army Communications and ElectronicsI Dr. K. Harumann-Rhyne Commann, Fort Monmouth, NJ 07703

Battelle Columbus -aboratores,, Metals and Ceamics 1 ATTN, ROSEL-TID, Mr. T A. Pfeiffer, Technical Dir

Information Center, 505 King Avenue, Columbus., Oh 43201 Oirector,. Electronic Technology and Devices Lab,1 ATTN- Mr. W. Duckworth Fort Monmouth, NJ 077031 Dr 0. Niesz a ATTN: DELET-D,ý Dr C. G. Thornton

Department of the Army, Office of the Assistant Secretary Commander, U.S. Army Tank-Automotive Command, Warren,.of the Army (RDA),, Wasfington, DC 20310 MI 48090

1 ATTN. Dr J. G. Prather, Dep for SLI & Tech 1 ATTN. Dr. W. Bryz'kI Dr. J. R. Sculley, SARD 1 0. Rose

I A)MSTA-RKADeputy Chief ol Staff, Research,, Development, and 1 AMSTA-UL,, Technical LibiaryAcquisitionr Headquarters, Department of the Army, 1i AMSTA-RWashington, DC 20310 1 AMSTA-1S, Dr. H. H. Dobbs

1 ATTN:. DAMA-ZE, Mr. C. M. ChurchCommander, U.S. Army Armament, Munitions and Chemical

Commander, U.S. Army Research and Development Office,. Command, Dover, NJ 07801Chief Resear'h and Development, Washington, DC 20315 1 ATTN:, Mr. J. Lannon

1 ATTN . Physical and Engineering Sciences Division 1 Mr. H. E. Pebly, Jr., PLASTEC, Director

1 Technical LibraryCommander,. Army Research Office,, P.O Box 12211,, Research 1 Dr. T. DavidsonTriangle Park,. NC 27709-2211 1 Dr. B. Ebihara

I ATTN. Information Processing Office I AMSMC-LD(D)r Dr. J. T. F.asherI Dr. J. HurtI Dr. A. Crowson Commander, U.S. Army Armament, Munitions and ChemicalI Dr. R. Reeber Command, Rock Island,, IL 612991 Dr. R. Shaw 1 ATTN.. Techoical Library

Commander, U.S. Army hateriel Command, 5001 Eisenhower Commander, Aberdeen Praying Ground, .D 21005Avenue,. Alexandria,, VA 22333 Cmand Abd eenBProvigernder

I ATTN. AMCQA-FQ, Mr. H. L. Light 1 ATTN. MDAR-CLS-PS, Ar J Vervier

1 AMCQA, Mr. S. J. Lorber U S. Army Corps of Engineers, Construction En9ineeringResearch Lab, P.O Box 4005, Champatgn,, IL 61820

Commander, U.S. Army Electronics Research and Dovelcpment 1 ATTN. Dr. Robert QuattroneCommand,, Fort Monmouth,, NJ 077r3

I ATTN ANIDET-ES,, Dr. A. Tauber Commander, U.S. Arm) Beivoir RD&E Center,.

Fort Belvoir, VA 22060-5606Director, Electroni(s Warfare Laboratory, Fo t Monmouth, 1 ATTN STRBE-FS, Mr W. McGovern, Fiei & 1tr Suo DivNJ '17703 1 AMDME-V,, Mr E fork

1 ATTN AMDEW-D, Mr. I Adler I AMDME-HS, Dt K. H. Steinbach1 A•4DME-ZT,, MIr. T W. Lcielaco., Tecii .,•

Commander, U.S. Army laterile Systems Aralysis Activity. I Mr M. Lepera

Aberueen Proving Ground,. MD 21005

I ATTN A4XSY-MP, H. Cohen Director, U.S. Army Ballistic Research Loovt O .r

Commander, U.S. Army Night Vision Electro-Optics Aberdeen Proving Ground, MD L1005

LbrtiFr eviVA 22060 1 ATTN SLCBR-BLT, Jr A M. DietrichiLaboratory.. Fort Belvoir, 1A2260SLEIR-BLF, Dr. A. Niller

I ATTN DFLNV-S, Mr. P TravesKy

1 DELNV-L-D, Dr. 0. Buser Commander, Rock island Ar~enal,, Rock j.1Ivind,1 DELNV-D, Dr L Cameron IL 61299

Commander, Harry Diamono Laboratories,. 2200 Powne- %111 1 ATTN ,,IARR-EN

Road, Adeiphi, MD 207F3 D ector,. J. Army lnii,strril Ui. Cniiire rini ikivI ATTN, Technical Informatlion OffRce R or,'.1 IL n1n e tI Rock island, IL b1299

SLCHD-RAE I ATTN AMXIR-.IT, M

r G B Nrey

Director, U.S Army Res'archi & Technology Labs, ,nemica Resei h md Drv.lopnvent Linter., .ee,3.mes Research Centei , Motfet I itld, CA 94(C35 Proving Grouna. Md 0ev0o

1 AT'N. DAUDL-O, Dr A far! son PoigGonM 1i A•. AVD-D DrR (rl~nI ATTN. AMSMC-CLD(Aý, :)r 3 Ri( hat,jonn

DAVDL-AL-D,, Dr. - r Statler, MS215-i1Aeromechanics Labioratory

No. of No. ofCopies To Cooies To

Commander, U.S. Army Test and Evaluation Comnmand, National Aeronautics and Space Administration, LangleyAberdeen Proving Ground, MD 21005 Research Center, Hampton, VA 23665

1 ATTN, AMSTE-ME I ATTN: Mr. J. Buckley, MS 3871 AMSTE-TD, Mr. H. J. Pete s I Dr. J. Heyman, MS 231

1 Mr. R. L. Long, MS 266Commander, U.S. Army Foreign Science ana Technology Center,220 7th Street, N.E., Charlottesville, VA 22901 Commander, White Sands Missile Range, Electronic Warfare

I ATTN*, Military Tech Laboratory, OMEW, ERADCOM, White Sands, NM 880021 Mr. J. Crider I ATTN, Mr. Thomas Reader, AMSEL-WLM-ME1 Ms. P. Durrer1 Mr. P. Greenoawn Department of Energy, Division of Transportation,

20 Massachusetts Avenue, N.W., Washington, DC 20545Chief, Benet Weapons Laboratory, Watervliet, NY 12189 1 ATTN:. Dr, R. J. Gottschall, ER-131, GTN

1 ATTN. AMDAR-LCB-TL1 Dr. G. D'Andrea Department of Transportation, 400 Seventh Street, S.W.,1 AMDAR-LCB, Dr, F, Sautter Washington, DC 20590

I ATTN: Mr. M. Laur.enteDirector, Eustis Directorate, U.S. Army Mobility Researchand Development Laboratory, Fort Eustis, VA 23604 1 Mechanical Properties Data Center, Belfour Stulen Inc.,

1 ATTN, SAVDL-E-MOS (AMCCOM) 13917 W. Bay Shore Drive, Traverse City, MI 49684

Commander, U.S. Army Engineer Waterways Experiment Station, National Bureau of Standards, Washington, D, 20234Vicksburg, MS 39180 1 ATTN: E. S. Etz, Bldg. 222, Rm A-121

1 ATTN:. Research Cente, Library I D.- L. Hunston, Bldg. 224, Rm A-2091 Dr. D. H. Reneker. Dep. Dir., Ctr for Matl's Sci.

Project Manager, Munitions Production Base, Modernization 1 Dr. Lyle Schwartzand Expansion, Dover, NJ 07801 1 Dr. Stephen Hsu

1 ATTN:. AMC2M-PBM-P 1 Dr, Allan Draggoo

Technical Director, Human Engineering Laboratories, U.S. Bureau of Mines, Mineral Resources Technology,Aberdeen Proving Ground, MD 21005-5001 2401 E. Street, N.W., Washington, DC 20241

1 ATTN: SLCHE-D, Dr. J. 0. Weisz I ATTN:. Mr. M. A. Schwartz

Chief of Naval Research Arlington, VA 22217 National Bureau of Standards. Gaithersburgh, MD 207601 ATTN: Code 471 1 ATTN: Dr. S. WiederhornI Dr, A. Diness 1 Dr. N. Tighe1 Dr. R. Pohanka

National Research Councl, National Materials AdvisoryNaval Research Laboratory, Washington, 3C 20375 Board, 2101 Constitution Avenue, Washington, DC 20418

1 ATTN-, Code 5830 1 ATTN, Dr. K, ZwilskyI D. Groves

Headquarters, Naval Air Systems Command, I J. LaneWashington, DC 20360

1 ATTN, Code 5203 National Science Foundation, Materials Division, 1800G Street, N.W., Washington, DC 20006

Headquarters, Naval Sea Systems Command, 1941 Jefferson 1 ATTN, Dr. L. TothDavis Highway, Arlington, VA 22376 1 Dr. J. Hurt

1 ATTN-, Code 035AiResearch Manufacturing Company, AiResearch Casting

Headquarters, Naval Electronics Systems Command, Company, 2525 West 190th Street, TorranLe, CA 90505Washington, DC 20360 1 ATTN, Mr. K. Styhr

I ATTN, Code 504AVCO Corporation, Applied Technology Division, Lowell

Commander, Naval Ordnance Station, Louisville, KY 40214 Industrial Park, Lowell, MA 018871 ATTN-, Cod.e 85 1 ATTN, Dr, T. Vasilos

Commander, Naval Material Industrial Resojrces Office,Building 537-2, Philadelphia Naval Base, Philadelphia, Case Western Reserve Univerýity, Department of Metallurgy,PA 19112 Cleveland, OH 60605

1 ATTN. Technical Director 1 ATTN-. Prof. A. H. Heuer

Commander, Naval Weapons Center, China Lake CA 93555 Defence Re-F,-ch Establishment Pacific, FMO,. Victoria,1 ATTN, Mr. F. Markarian B.C., VOS IBO, Canada

1 ATTN. R. 0. BarerCommander, U.S. Air Force Wright Aeronautical Labs, Wright-Patterson Air Force Base, OH 45431 Ford Motor Company, Turbine Research Department, 20000

1 ATTN:. Dr. N. Tallan Rotunda Drive, Dearborn, MI 481211 Dr. H. Graham 1 ATTN: Mr. A. F. McLean1 Dr, R. Ruh 1 Mr J. A. MangelsI Aero Propulsion Labs, Mr. R. Marsh! Dr H. M. Burte Ford Motor Company, P.O. Box 2053, Dearborn, MI 481211 AFWAL/MLLP, Mr. D. Forney 1 ATTN, Dr. 0. Compton, Vice President ResearchI AFML/MLLM,, Mr. H. L. Gegel1 AFSC/MLLM, Dr. A. Katz General Electric Company, Research and Development Center,,

Box 8, Schenectady, NY 12345Commander, Air Force Armament Center, Eglin Air Force I ATTN* Dr. R. J. CharlesBase, FL 32542 1 Dr. C. 0. Greskovicn

1 ATTN:. Technical Library I Dr. S. Prochazka

National Aeronautics and Space Administration, Lewis Georgia Institute of Technology,, EES, Atlanta,. GA '30332Research Center, 21000 BrooKpark Road, Cleveland, 1 ATTN: Mr. J. D. WaltonOH 44135

1 ATTN, J. Accurio, USAMRCL GTE Sylvania, Waltham Research Center, 40 Sylvania Road,I Dr. H. B. Probst, MS 49-1 Waltham, MA 021541 Dr. S. Outta 1 ATTN, Dr. W. H. Rhodes

National Aeronautics and Space Administration, Washington, Martin Marietta Laboratories, 1450 South Rolling Road,DC 20546 Baltimore, MD 21227

1 ATTN, AFSS-AD, (Iffice of Scientific and Technical Info. - 1 ATTN-, Dr. J. Venables

No. of No. ofCopies To Copies To

Massachusetts Institute of Technology, Department of Sandia Laboratories, Albuquerque, NM 87185Metallurgy and Materials Science, Cambridge, MA 02139 1 ATTN, Dr. F. Gerstle, Div 5814

1 ATTN-. Prof. R, L. Coble1 Prof. H., K. Bowen The John Hopkins University, Department of Civil Engineering/I Prof. W, D. Kingery Materials Science and Engineering, Baltimore, MD 282181 Prof. J, Vander Sande I ATTN, Dr. R. E. Green, Jr.

Materials Research Laboratories, P.O. Box 50, Ascot Vale, 1 Director, Office of 'cience and Technology Policy, OldVIC 3032, Australia Executive Office Building, WashIngton, 0C 20223

1 ATTN-, Dr. C. W. WeaverSubcommittee on Science, 2319 Rayburn House Office Building,

Midwest Research Institute, 425 Volker Boulevard, Washington, DC 20515Kansas City, MO 64110 1 ATTN*, Mr. P. C. Maxwell

1 ATTN, Mr, G. W. Gross, Head, Physics StationAerospace Corporation, Materials Science Laboratory,

Pennsylvania State University, Materials Research Laboratory, 2350 East El Segundo Boulevard, El Segundo, CA 90245Materials Science Department, University Park, PA 16802 1 ATTN*, Dr. L. R. McCreight

I ATTN,, Prof. R. Roy1 Prof. R. E. Newnham IBM Corporation, Thnmas B. Watson Research Center,I Prof. R. E, Tressler Yorkstown Heights, NY 10598I Dr, C. Pantano I ATTN*, Dr. G. Onoda1 Mr. C. 0. Ruud

State University of New York at Ilbany, Departm.ent of Corning Glass Works, Research and Development Division,Physics, Albany, NY 12222 Corning, NY 14830

1 ATTN: Prof. W. A. Lanford 1 ATTN: Dr. W. R, Prindle

State University of New York at Stony Brook, Department of 3M Company, New Products Department, 219-01-01, 3M Center,Materials Science, Long Island, NY 11790 St. Paul, MN 55144

1 ATTN-, Prof. F. F, Y. Wang I ATTN: R. E, Richards

Stanford Research International, 333 Ravenswood Avenue, Technology Strategies, Inc., 10722 Shingle Oak Ct.,Menlo Park, CA 94025d Burke, VA 22015

1 ATTN: Dr. P. Jorgensen 1 ATTN, Dr. E. C. Van Reuth1 Dr. 0, Rowcliffe Rutgers University, Center for Ceramics, Rm A274,

United Technologies Research Center, East Hartford, CT 06108 P.O. Box 909, Piscataway, NJ 088541 ATTN.. Dr. J. Brennan 1 ATTN. Prof. J, B. Wachtman, Jr., DirectorI Dr. K. Prewo

Syracuse Universityý 304 Administration Building,University of California, Lawrence Livermore Laboratory, Syracuse, NY 13210P.O., Box 808, Livermore, CA 94550 1 ATTN. Dr. V. Weiss

I ATTN, Mr. R. LandinghamI Dr. C. F. Cline Lehigh University, Materials Research Center $32,1 Dr, J. Birch Holt Bethlehem, PA 18015

1 ATTN, Dr. D. M., SmythUniversity of Florida, Department of Materials Science andEngineering, Gainevislle, FL 32611 Alfred University, New York State College of Ceramics,6ATTN Dr. L, Hench Alfred, NY 14802

1 ATTN- Dr. R. L. Snyder

University of Washington, Ceramic Engineering Division, FB-1O,Seattle, WA 98195 Alfred University, Center for Advanced CerYmic Technology,

1 ATTN, Prof. R, Bradt Alfred, NY 148061 ATTN, R. M. Spriggs

Westinghouse Electric Corporation, Research Laboratories,Pittsburgh, PA 15235 University of California, Center for Advanced Materials,

I ATTN:. Dr. R. J., Bratton D58, Hildebrand Hall, Berxeley, CA 947201 ATTN, Prof., G. Somorjai

Battelle Pacific Northwest Lab, NDT Section, Richland,WA 99353 Boeing Aerospace Company, 11029 Southeast 291, Auburn,

1 ATTN, Mr. A. Birks, Associate Manager MA 980021 ATTN, W. E. Strobelt

Rensselaer Polytechnic Instituce, Departmert of MaterialsEngineering, Troy, NY 12181 University of California, Materials Science and Mineral

1 ATTN, R. J. Diefendorf Engineering, Heart Mining Building, Rm 284, Berkeley,CA 94720

Oak Ridge National Laboratory, P.O. Box X 1 ATTN*, Prof. G. ThomasOak Ridge, TN 37830

1 ATTN, P. F. Becher Director, U.s. Army Materials Technology Laboratory,I V. J. Tennery Watertown, MA 02172-00011 R. Johnson 2 ATTN-, SLCMT-TML

5 Authors

0.3m - 0 a, 0.3.- 'w 43 -0 0W 30 CL-3 a) -3 04 w A Olt3

61W .343L a do .0 3 1-> a w T303= M -0 03 M- - o--~

.!ý ... ' o 303--!oO 00 w3m0

a 00 "-> 0 3.0 0.030 E ?c, 0 '. ..3. 0 0-1 1..0 43423 . .- A23 34

43. a, n IA I. Z0-. 43.

o0. A .. 0 0 I2- E~33 43 %JC 00 3 > 0 >1 - O -- W , 4 CW', C >

0030 3: 0. X3 . 03)

04300.3 0.0304 OWOO 3. C=OA.

4J.0= r0) 3M W 0 M .00=3 0 a.341 0 Q *

4C.0 oo,0 1031 = WOL 30 Q. 03w-o O a.0&-.

3c-S-0 *o &~woa'-

0 0

S .30 0 3 W.0 0.43 .03 C .0 0.04-.) .0

0 c .33 0 -2 0 0,c 4 .304-3a. 00.3 30.33.3 a. 00" 304-3430.3-0.2 - w.~ a. a.'' m. 2>3=a.0 01

qu- .30 03 00 0

.x Na 3-. 43- c :..a M W < wI W 0. 3: >.O .3 m 3a)a ~ 32 00 m-.>,3 ME co E -. > 1

CO=0 m wo; 00a. FMI 103.403 'o43 *w 4E -a. 03. 0.2

.3 cE-0 Nu 43 -o r_ 43 C.30 w'.00O 030 S- c4.3 c03 cm L 030 43 0.

.30 m 03 43 W0'00 I-0 -1. 4-3 1-3 W: 30ca- IV 3.4.0 C u 0 m4.4'A O w m. .1C u 0 m0 W-4 A 0wI- .0 4 W -.030~ mO. 30i z 3- e IaurI~ .0 C'..04 2.- -43<0

U~L fu M><~ r= 30 m0. * 0-v m30 -c -V.0-3 N Q.~ > ~ O4C- c "'33 63-~ 0.ý .' OW .'1. 0- 3

mci t - CL.0030 m - MC3 NL- 0.- .03 .- 4.L 0ý0 *.0 =0 I-"-. .- x0 0 a 0 C0 I-~4 .33z;,

C330, Ln"- C 303 03 . 0 clo-04 030L1-A- J03 COIDL E .0 0 0 Q- 0'O4-=0 4C0 3'3- 00 21 ! 0 o 0 OZ30300w c 0 10 002c "L

WC -1. 03 033 4341.0 3 04.3 Cu1 i-:2.- C 3 1-3

m N . o C 1-.0 003303 203.4 *N "U.4 .3c - W 1.. 2 00U 0300 01 0

'-0 IX :43 "- 4) 'D - 0.43) 30 V;:2 C-j=.0 0. 1- Z-30 = t ~,* *-, a) 0- a06 W 00 -

00 )L O.4 -3 4 '0 .33033 1.4 c 30A..33 C) .400 4-n01.0M4- I- Q)303 0. 3-1 "I00C3 S. _03 c-" -100a.

-3 L1bj 06 Z0 - 9.)4 m01 00303 -1 301.J va 2 . .034 m u - 0030'a0

0 o 4 43.32cat3 1 S- w a x C) 0 W.a20.3E ,3c34-Q1. ,c 00 1- '. C. 0.61. 'a0 o'

r 2 (M03 03 43 u 3 0C23014300c .300. 41 0 0. a 03 0 00-0 (1 022 ) 00 0.0 0W C 0.3

3c C s- 0 413- !2- ,1 a. 4-OW **'-0 3

3.Ma. 'a--- 0 '0 30

0 307 --L I-0a, -- Z-- ,c w0- Lc. C.020 os_- U- s 3 .1002m0.. E

EF-1 -i-s- -s ýcE u 0.03 = $- 0 C L '0- a

43 W116 0"43 30 0c '0 .3431'> 4'0 033- =4

O.0 31 CM30- 20 .320.3 0'

-~~~~ 0~- 1,-3 1...04 0 C3

*0 M-0 M- 0 M" 0sA->1.0 0>. 01 -. 30 w m 33 3.

*c ."I Olt - -,a Olt 0 v

1.3W .0ý( 0 C4 43l .3 0 ' 30 0.... U3 3..3 s- 0 C4 30 w3>0 3, 1-.3 4

-l 3 W= a. .3 0$~.3 00303 -" I3 a. 0 .M .3 -33 "

E Z -- T 4, S-C4 3/ 0 E0 -u m,3 43 4 0C 0 30--o C03. 043 J- E I4 0 ur

05 a.30Q >0LZ 30 E L cc w o u >WO 0 >, C3E0-Ato 43v

0 >

0 0 10 0 0' > .31 c Wr.. 33 1.03m

. 0 a ro 4 1 " E O cw3 - 'w m . 0 = 1 C ,4 3 . 0 2 0 . 4 - 0 M1.0 30C." 13 0 o 1 66 33 03: 01

0.33' 00 0,; C

a. 0.3 o' =3 0.-0 a. a. 0 o> 0.'*0 M M C wo'~- m m0.00 33-

4 0-0i-Z *' >.1. " - w30 .' 4)1>3

0.3.ý &~ a. 39 >,.c 30 43 '03. C .3>3003.3030 - 03 -a. '0 1..43.0 304 3.3.C0 Q-3 a 0 0 .-. . 3043

co0 .304031-0.. -- 4 03 '300300-..0w m3 4300c 43D. w m- 3 - 3 302.0 4341.033.no .1 3.0 43 0 030 1.01.30 5. E30 4 0 03

003-Ew430 J I0 L33 RD cc 0 - WW.0 L. w 0 43 0

I- 30 E503 43 30 93 . L 3. 1.0 &-43 >-03 43O 4)-'. .0 =.-- m::; 1.X . 0' C 3 3 3 A 0 3 303 .- 3.C WM' -0, 3 3 3 A

M"3 N) 08> "-: 043C.-1.% 0 >I-33 .D-' N 0. >O 04 01 o-'3

WE L)".3 ý -~0.4)1 %- 0.0>4 1.33 >,-4 -j '-0. . .00.0O>3.3>",: O li LA -303 0 C1. .043 0,-04- 3 30O..A 00 03. 03 -334t), InWC 10 4 c3 000 1. 3'4 U- , 3,033 _,- 00 21 , D'

0W.4~ ~~~~~~ coo. 03,3 =33 m331 >330 0 3. ~ 340 433.'30

.00.-130 3 .3 -A0 .0:000 0 .0 blue !2 43 ) . 0. 0 1,030-00cu040 -j 0 I- ý- 43 300 33 .a33- w3.0 '-0 4- 43 '.->.3.0.3

co 0CO'0M30- c ) l 130,-.330 -I C3- 30cO'3 cm, 13-0.4 300 --C0 w .31 30A C 0) co 0.0m .301.03 1.43 0

303 .0 Q exL)0 a

30E00Q. 04 m330333.33 C u 3 0-JCL 043 43.3 0. 0 M>143

10 0 04 tn 0.30 .0 340m 4 1.3.41 .00 1- 30u~' 'a a. 0.4- '0-

E43'00oi-1 3= C *0 30034004 .'L.130 C, 0 w00303304M UCOn 3006 30 1.3 1.- u0340 <.C00. 3 D0 1.1 . 40.

E.'000' 30 c0.0 m.04a31 wo. 23 0 -0) 30 CD30 .0431

E ~ ~ aC . 1 43.. L 0, L L x EC --- D; -m 0 L) 00L . F0.13030- L0 3, ) IO0La =0..

3.'

L =- M )M-ý0 L 0 L- - E - 0, >,S = =4 I.- S. = - '( 0.'L1U---- a,---------'----- --v---I) 0