UNCLASSIFIfED

AD 2 6 4 841

ARMED SERVICES TECHNICAL INFORMAT!ON AGENCYARLINGTON HALL STATIONARLINGTON 12, VIRGINIA

w

UNCLASSIFIED

Best Available Copy

NOTE a oc'~rnor othaer &rarin-gs, speci-:!=atic= or ctber date ar-o iusiPi fcr=- .jny q-oeothUer thaqn in v:,r! + % deflijdte]7 re3AtAed

go~e~ezi pr~~st exaticm, tbhe ii- -:.G--e-oLeret there-by- Incars no respomisib;L:ty, nar anyobligatimn~to~r amd the fact tlhet the 9--rer-=en- may hz-.e fo~m]atted, ftrnisbea, z-- in any va~ysurpjlle-d the said dravings, specfinmttims, or- o-tbhed-stsa is nct to lbe regarded by I-,%Lication or o~ther-

.ieas I.- any7 mm=r l-icens!=g the hole oar anyat-her per-so orm 00! oztim.a ouyray --ri&tor pe==issio to =a~faetmre, =se or swef azpattented invei-aian that =ay In amy uwy be related

i -c T!--- Acce1lt-.%tci Cc rrsof Metals

Da-:-- A

4EI

- ~ - -i i ii.--~~, ,-~--.. .-- - -- -ii, :

-.- m

UNCLASSIFIED

Contractor: Akrmy Chet.iical CenterContract No.: DA 18-108-405-CML-518

Eighth Quarterly R--e=rt

Covering -z-e Perioc

june 16 - Seotember 15. 1961

Ti:le: 'hE ACCELERATED CORROSION OF METAIS

Prepared By

Sen;s. investigator: Henry Leidheiser. Jr.Assc-iate: David A. Jackson. Jr.. Research Chemist

5 Septet.n,7r Z6. 1961

Copy of Copies

UNCLASSIFIED

AST1'Ai- lb

I:-

-. -_ __- ; - __ _- - - - "__. . : . _,, , ,__ _

TAIBLE OF CON-TENTS

Page

ýntroduaction I

Descri-ntion of -Auparatus 2

E&cnerim ental Prc~ce-dire 5

Rescdts and Discussion 7

Exp~erimnents Planned for theNext Qi-arter 355

Bibliagrapiry 37

z -

RiTRODUCTION

In previ-ous re-ports (1). -,he oxidation of aluminum

in contact -with mercuric halides has been studied. and the

influence of rclative bumidi.:t-,r on the oxidation rate was

nctec - In this report period the Al -RgI, system bas again

bee-, used for continued quantitative measurements of the

oxidation rates- The rate .3-1 oxid&tion of aini= ~ a-..

in !:-e presenct- of Hg!, h-as been studied over z reiativ<

hum-iditv range of 36..4-100%~ at a constant te=ýzrature of

30@C.. A great increase in rate of oxidation- has been noted

inthe 60-80% RH range-.

DESCRIPTION OF APPARATUS

The aDparatus described in the Seventh Quarterly Report has

been further modified to in-clude a p~ressure guage (Fig. 1:B 3). which

was calibrated ag--nst the mercuxry manometer (C). This bellows-

type guage was specificzfly designed to measure the small internal

pressure decrease in the reaction chanber; atmnosp~heric pressure -was

the -reference- point. Once the g.-ge was calibrated, thc manometers

were disconnected. and the syste= z-cseaale-d A-!! oi~ f AWOZ

in- this revort are based on prc5sure rea-dings obtainedA !,: this g~a--t-

A pobt.ograen of the entire apparatus is seen in Figure I- The

vacuum pizmp) (J) was used interntittently to check the system for small

leaks. A detailed diagram of the reaction chamber (A) ma- be found

in the previous, reports (I)-

L 3.

-.2

r;;

-- 4.

ITDcs.:riptior of Apparatus for Figure 1

A. Reacucn Chamber

SB. Pressure Guage

C. Wfater and/or Mercury Manometer (:."ow nt i, use)

I D. Barometer

1 E. Conscant Temp~erature Bath Control Unit

F. Fan and Lramnp Control; Barometer ,A-justmcntIndicator

G. Constant Ten. errture f.-W'tr Bath

H. Variable Speed Water Pump

- Variac for Water PFlup

J. Vacuum Pump

3=r

17

IV

I. -

l r.L

~.Z.

: mo, . irlr i ' I ',, ! I I'q 'II

i ,..

EXPMERIENTAL PROCEDURE

Reynelds 99.999% aluminum cylinders 11'2: in- iiameter and 1/4"

thick "wvere degreased in acetone and ether. Exposed su-•face areas of

-hese -.-a-nples rmeasured ;-pproximately 1.25 cmn.

The cmidation of ;-e aluminum samples was initiated by the attack

of Hg-1 vwhich wa-. quici-y reduced to metallic mercury. The manipulation

of the ap•aratus for this is described in prev.;ous reportsjl). Upon

algamation. the oxidation proceeded; the rate berg -rea-ly deter.in- d

by the relative humidity inside the rec-a cba-nbe7. The desired relative

humidities were obtained by pla•ing various saturated - solutions in the

reaction chamber. Both thermal and humidi- e-euilibrium were facilitated

by the use of a smali fan which maintained the inte-rn-a atmosphere in a

continual state of mo-nemnent- Upon reachin-a e-uilibrium. the renction

Sas begun as described above. The oxygen consumed dinting the reaction

-"was "-- easured by the decrease in pressure inside the chamber. Since

pressure was the measured parameter. close temperature czntrol inside

the chamber vas essent-ial Temnperatuxas were maintained at 30. 0OCC+

""a- 0.30 throughout all the experiments. Measuremeats of tim-, te-m--erature

and pressure were -made at 5 to 10 zm-ime irn: -r-als un-il the oxidati.=

S_1_slowed cz -1 - Corzectious necessitated by changes i'-

baxromerric.)ressures were made.

Values of AP in mnm Hg were con'rerted to AWo? in mglcmz2 from

zh I -de follow•.g: vA

AW= T ..

?M;

I1L.,• i " T i l ', i l Jil in l I' II I ii I ll ,,

where VM remained constant tli.rcighouxt the experiments- Values of£ ''Z5R

.... W -xcre p~lotted vs. tim e i.r eac -'ceximn-t an h-lopes of the linear

portions of the curves -- ere determined-

Several satirate-d salt solu-uens and the associated relative humidities

under ecuilibrilum conditions are listed in Table A.

Relative Humidities of Severa! Saturav-d S-altsolutions (41 at 30'%C

Solution R- H.%M

Distillee. wate.: ion

(INII'4)HzP04 9Z.-9

BaCl2 lz- hO 85

(IHL),SO. 81.1i

-2'C O3 72.7

NaNO2 3.0

Br- Na ZHZ0 *56-.2

Cr0 3 +4_6

- Kal. 213,0 36-4

F- Etrapolated value (.2). (3). (4)

irN

I i

R SULTS AND D!SCUSSION

Whereas in earlier exneziments. the linear portions of the

oxida&ion rate curves were us-m-.!v preceded by 1-w-rate induction periods,

IIin the .present . -perintm~ts no g2. eat ;_nduction period seemned to exist excent

in one or two cases at high relative humidities.

By vlo".np --- e --. v-values of ,.Wc, obtained f-om oressure

r-ear--g-s. each rate curve exhibited a ch-nracteristic linear portion from

whic! .he skones -were gravhicaU,, dete-•ined. The slozes of the linear

portions o. !ie -Ate cux ,cs were -?!.:. --:-=- " anIe at any nar-icu1ar

relative humidity. However, as the relative humidity de:- eased, the

slopfs of the rate curves also decreazcd_.. The slopes of the rate curves

are listed in Table B. wi-fth the ex-sting relative h" miditie-s obtained from

the saturated salt solutions.

At low retolatc humiditnic& 64 RH anii bcnaw). thr extent of

oxidation was verv sall, and the associated sloveos fr the rate curves

could ordy be determined from the first few me-asur--r.ents in the 1.0

minute time intervals..

Figures 2 through 7 arc rate curvcs for ex::eriments at 10M R HI-;

Figures 8 --d 9 at 9Z-. 9 R.- ; Figures 10 through 12 at 81. -5 R. N.;

ig•u•res 13 thir-.ough 16 at 72. 7% . H-; Figures 17 through 20 at 63%R R H.;

'Figures Z1 through Z6 at 36.-Z , R.H.-; Figures 27 "h-ouig 30 at -4.4- 6 R.H. -

Figures 31 and 32 at 36. 4% R.H. Since th, variation in the extent cA

' xidat= -w-as wide, three diffement scales were necessary to plot accurately

the oxidation time curves.

..... . ... - - - -

a 1 8.J

TABLEE

Values z,.r the slozes of oxidatý: rate curves~ at d~iferentrelative humidities at S3541e-

SaI. -d alt Relative Sic~pe(mn) Ave- Slope (i±.-sohutzon used Humidity ro) MFOIcn 7nr. mOImlii

DiL~dWater 100 *0. 630

it 0.570020-622 0. 6141! 0- 616II0. 59 1

2: it0p567

22 0. ;66

0-566 ~ 0-583BadI7,>.. 2Ho *0-613

222 o-556 .5.1 ~~*0-565 0 5

81.1 0.o-5A4IS 2.*0-515

U *t *0 = 0..520

H 0.4962. ~ 0.487i

'Na(N0C3 ) '?Z-7 -10425

23 tb_.Ing 0--409

22 *1 0.3SINa4O,)63.0 0.2,70

2- 0.270 .7

NaBr ZHr,O *e-o 2~ 193

0.180a 21 12 0,200 o~

~ .1. H0. 240

U U 0.210

Table B (continued)

Saturated Salt Relativo Slope(m) Ave. Slope tFSoh-"tion Used Hum-idity (Ii'gcr 2 mn ngo:Icm2 Ir&

Cr03 44. -6 0.1370. 130 0.136

2! 0-139:1 0.138

----- 36-.4 0-083vI t 0-076 ..01-OS

Values talken fi-oe Sev-enth uaeryReport

'Short-term o. cidation

FExtra-aolated value (2). (3). (41

The inFluence, of the relative humiffity on the oxiL.....tion rates is easiliy

n.o'ted in Figure 33, wuhere !he average vallues of the di~erent slopes are

-Diotted vs. -he rela.-zve humidities a-, which the sloves were determined. The

change in- slopes with change in re-asi-ve humi-dity- has the appearance of a

lazv-S curve. In the 60%- i5e, R- H- range. there is a we~s-defiacd increase

iu. oxidadion rate-

T'z.-%m~rage values -1-r th'e slopes at high ela R. H--. (particularly near

l00ro R- H-.). as well as the widde ranges at each %R-. H- leasis the

to Beclieve that the gradual taffig-off of the cu=-.c -a.L uuc .- e.o ý-ea

cui-;ficzlty with whch eouili riu-m -waz ;.b:--ized- it is believed that thr; mo~st

likelly path for the curvue to follow in this region is somewh-at hig'her tlhan

shown. and should approach the higher limits of the-individ-"al ranges..

The extent of oxidation in the 60-75%~ R- H- r-an2e: indicated a more

j pranounced increase than is shown by in values in Figure 33- Vai:Oation of

10.

oxygen -consumed uitin %R. H- during a 150 min-=e effective oxidaticn

p.trzca disregazdiag induct-ien 2iAsamd by iextrapolation of the dAW vs.

turn - t.rves for s nort-term reactionsl indicated that little significant

oxidation occurred until the relative hritli-ty :reacl-e-d 6ove R-H. At

av rcximately 6T~ . H the ofun 0 oxyge- c:Dnsi-med suddenly increased

with increasEina R- -H.;i at 4 0 54 R- H. an average of cnly 7 r-ng oygen

wenc--)insxz-med in 1581j minutes. %vhereas near !OV,2 R- H-. annro-ximateiy

83 mno ozyzgen were consumed in the sam-e period.

A t~ei~c16 r--- mnwrie -a-.~ made of two alurmnum samples~

sim--azzeo-aslr ox-d~izmcg at different relative humnidities; - =amnnle near

80V, R- H.-i and the other near I00 WFLR H. Evnthough th-,ere -Mas -270t~

difference ;n reaction, a more str-ikidng. difference was desired for the

tunet-la7nse films. This will be accompalished at a later date by p~hotgraphing

e-n.-riments near 45%s R- H- and I00o R. -H.

Preliminnarr mn-icros-zopic investicgatiens at ro0m condlitiomns on thse

oaidation- of alumr-inum initiated by Hgi, were begun.m A-- zaoýsr~ea =-.I n-

sainnle was cement-ed to a slidce and obser-ved as a ziny crvsta; of Hg!, as

brought in contact with the -nma The reaction annea~zed ict-k. nlace in

several st.ezs- F-ýirst, the salt se-m-ed to =cat.t instantly causing adark

area to :o--=, which in turn snr~ead rapidly from !he pouint of contact over

* a relaztively large area- This dark area anoeared to be a clear licuid ui-,Aer

vwniclh small bubbles of gas soon developed and came to the surf-ace. The

length of time this gas evolved depiended on whrether the point of co-nact of

the salt w-as on the edge of a sample, or on a 214t surface iar removed fromn

Sthe edge. Gas evolution lasted longer when the salt was placed in the centra IDart of the s•*- -

As th.e gas evolution diminished, the meitaUic appearance of mner-cur-

developed. A ti- avyer of clear liciuid still covered the surface of the

-- ercury at this point. Soon, this k--.ar lin-id dis•appeared followed by

un~o.--m -ormaao- of a .im over the s-jrLce, causing the metalliz luster te

be dulled greatly. This film grew mo-e and more opaque umtil the presence

o-f the white oxide was aonarent as the film thickened. This oxide formazion

was more ra--iA at the extremities of th- darkened area, especially if the

area was at -he edge of - sample.

I7

1

i Li: I~t

= =- J, _ _ _ _ _ _ _ - _ _ _ _ _

-- ---- 4--- -a

- T60T<~~

140 .n : ----- 4 - ~ -----

120~

---- 4-

0 so lot I. -0-20 5

-~im -mri es 30.-. . ..

160 _____-- - --------- .

2-11

40-

4---.

so-0O 10 ]SI zo 50 -

-~~Tm (minutes),-*~~

_8 ___

_ _ _ _

'*7= 7-.

3 - - -- -

.4 -t

* -z_ :4- -- ----.----

~ .--. -- - --

s-------- -f-!-7T

__ __ _ __ _ __ __ - -A-

44

-4r

-o SO -s-~ozozt4 --;j351

Time_ ----- 7--s -----4

---- -- --

7- = ---!-7 ;

-------- -

so/ -----

.. .. .. . ..

i20~ - ------ -~I -

Time (miute. m-oS

--- -- 47 .4 1-

~~~~~~- -- -----.-- ,--.

180 -.- ;-4--. 4 - 4

7-- T _T4 7 --

__ _-~j-~:io

so± - A~

iou ~______________:77-_

t -

- 1

40- -- ~ -:

* ~ ~ s 10________

Tim I -.4.tes am.

........... 4-!-- ~ - ~

- '. 57;

-7--

7-a

6 1 --------.- - - - -

40 -- a - ---- C-- - - - -~*

16O~~~ - -. . . . . ..~~- C. - . - - - _ _ _ 1 ~.

_ _ _ DO_ 10 i O20 :-! -

A ~ " ~ ~ -- -

711

74 _

SC)iI~.--

-44 74

__ _ _ _ _ _ __ _ _ 0

* - -*---4- - - -- - - - - ----7

- -t----------11-- -5 20 0 - - -

Tm (mnts

S

19.

v---- -- - -

� - -- - ____________

m 0C61 . -- - -2-�����-

-,-- 4 "-*

___________________ - -�-- -. --- i----.--.-.-.t---,-- -,- -.

1-.,4-.- -�-

-I:1

160- -7I

___ ____ /-1

3

C, i��- - _____ --- 3

.7-.-.- --.-- -: - f.-j----..---_________ --

-4--- -[I

80�2j� ------- 3---- -

- .t- 4 I ___________________ ________________

* ..

4- *- �- �

£05 :- -- ���- ___________ _____ -

� -r� -

2�

� - �- �-. : 8

4-- _______________________ ____________________________

� = -. :7

it�=- � _________ ��-�'�--

* ..-.----..-.--. ;-------

o 50 100 zoo zsc�-

2000.

-0 -z -----

16~_________________

60~- -- - ~ - -- - -- ------

- ~5 inn- zoo--- - -

TieOists m

100_ _ _ __ _4-

Del..-.;ý-T *---- . z :--

4 ~ 4

-~~- .- --

j.-

____________________ - : 4

-- BiE-IR~* -_

0 z ~ - - _

Time-- - , ---- 4-.

Z(A-

0I 487 __ _ -,. . - -------

.Ti3L~C~~-~__ -- - ____

inn- C48 ------.- -

17 --- r--=1- 4

TA

Time___ __ _ --- 'I.,---

23.R el. lizzn ?.----

-r 3(1. -3 L (7

so-

.T

0 '0 40 60:;o 2: 140Time (minxutes) 30.

Iw

a - _______24.

7 - j ' :• ==_..i.,j

-- • : .---' - .-" . . . . . .I••-•.. 7-":-• '- •-; ::" -... ------- -

* _3

* . ... . •: ... . --. -: , .---- _1 --'•' .4 • -.- Tr-+*_•E -'--

or -F-,-i2 " - -- .-•-= =• i-:-- •-=:-:---=•• '--i- - • -.- -F . -_ -i--.o• -j :4: -t-• = = I---• :-a-, • '•7•:-• --:-

44

- - - - - -- -- ----- " ,- . - . - ---

L -I-- -I-:LL - : --.- : i--4...•+-:,-.... -,. -c-+-

--. $ a -- .. ....

S'__• - --. -.-.... +_ *•._...• __...+••___._.__ __ •_._ . --

i ' L~~~~~~~~~~~~~~- - - - - - - - --- - - - - - - - -,-,..•- --. ---''''•:-- • •."':''':, .:---- .

+ -- ,L. _ ___+..+.________

r,-

,: ~~-.~-;-4-_. +....

.+,. - -.-...- - . - . + + --- -t-- .,+. -';,_ - 4- 4-.. . ...

4-4

-- -- ,---i-i ------

i---Time -- 4 *utes)

S. • r -!i~ - - l -. I 4 r - - • -+_- _'•

I25.

_________ - -- ---- ------ i- -.------- �

I 1T�295�7� iE�)2 -- -$ 21-- ���i-----j-- 4 -- -x -

-- . - .- �- 4-r---- -�

180 --

- - - - -� - - z.z�-� -�

4 1 -*'---4 -4-4� -�

4

- 4 -- 5-4--.- -4

____ ___ I

4 :4

- - �1� 4 4 4 - S

- -4---- -- -I-- -. - - - -¶

r�1��*��� _________

4-f

---- a- 4 ----- 4--- 4

E -� ___U 100 4 . * -� ____

4- -- ------ 4---.--- - -- - - - -0 ___________________________________________________

_ .- _*----

i * IIT � -4-i-4<1 �0 -------*- - -t -. - -r

-4- -4 -4--- -- 4 - *1jE 4 S

II I ________ -i -911cr �- �t--:-- . * - - .. � - _________

��I-5 60F�---� �

--. -- 4- -- 4

-I g____________________________________________ ��?��

-1--. *- I

_____________ ________ A----------------------------------------__________________ � -� -. 4A43 � � -- w;w:�. 4

1

_____________ �- 4zo F �-�-.2�-- � i - __ -. -�-�-�

4.. �

-

-�

I - - I- -1-� .�±zt�-4- .4- .- �..-.± ___ ---e-:---- -¶ - 4 ----- 4- � I 4

W �I�-i c-A-- - -�- - --- -x'4 --.---5I

- 1...4

..... j 1-z�z� a-- cra.�ca���u

p ,I) JOb 1�iiTime (ImIalnes) -�

- - �-- __

,�,- -

4-

___ -.------ ________

- -- '6- --

* . . - �����7*�* 4 -s - - .------ - I* -- .7--

-� ______________ * - -

-I- ;;-Ret �w £�3�:: -

T00 �t �0ZCY -. :-:� 3 7

��r-r �I

I - .4-

_________________________________ � .- �. 1

_________ _______ -:4

* Fag i7�

I

r_____ _ _______ I___________ * ________________ �1�'----�

� __________ -r � - -7----:zzrz _____ - tI':I 2 -�

--- t **----

z4�±� 4- - 4 �____________________________ - -4-------

- -- 7 -*-,----------4---t- - S -- -- 4- - -- �-�- -�------- 4 ------- --- i, -

__________________________ -- 1--- -4---' -- * ---- 4 -'---------- - -

S * rc4go�o3� ---------- -- -�------- ______ -.S ..-- �---U-�4-J- r- -- -� -' -j�E�- - --- -- I

- .. - 4 - -- , - -5--

-- - - -4 ----- A---* ? � -- -- * U

'---7- I� --

�-a--.--4-7- � -����--- --- ' ---- 7 7-- �44-

1 -�=�T�-T>--?--- -- --- :1-- ---- - .-- - -

20 _______ - - -� *

-� -'�' ________ _________

II ______________________________

__________ 7 . - -. -�--�� - - -.- ----T?� -� � � -�1� � � - 4 -7 -

1��z" i�

5a* ______

U

C

J-7

40~~~~~--- -- --_ - _ _ _ _ _ _ _ -

7-Zrz7-4--4.. zz - 1Fý*

-. - -- ---- --

=77 --- -4

~zo - -~~ .- --4-___ _ 1' __ __ __ p __ __ __

- 44-.

47.. -

--------- 4------

o ~ ~ ~ - --------- "-- -

-~~ =--A 21Z

4 -t

E4L E41 80 10 !2-

~~~T- (-mainuies. . . .

Zak

20------- -~*-4 i 7 ~ 4 . -

247-

:Elil

V e(inutues)--

____ _ _ ____ _ _ ___ ___ ___ __ ____ ___ ___30.

T3i9-t- _-9:----~-

-- ý--- : NA~~~-

-- - -- - - - - - -_ _ _-_------------

- -. -z-...4--

T 30: O2:÷;02 -___________________

=~ ~ -J - ----------__

-- AV-- - vz -_ _____

7 -~~~

Fri1

-- 20 -~ 40 6e so ~ Z 10 :2D

Ti m ( nii mut-

--- -4

-~~ ~ ~~~ --- ----- ~- - - .. ---- ; ~

T- 4 - .

- ./ . .' . .....

0a 40 -os UoW

_____ ___ _______ -1I

i r ------ -

Ai

IQI- - - M

iL -----------

-- _ ------ =z

- :•v . u - - .-- -Ot' ...-T- .-i- *4 .. ... . ... . . .... . . , t.. ., •. . •

-- A

-- J+ + - -: - -- • |---:•-l +-+-- -- -- l-: -• - -•] .---- --,-- .... _ _ _ ___ ___ -i

014-

_ _--__ _ ___1.___1 .....-gs z - -- --

•• ;-_• -+ • :-:_-== ... • __.-_--. ___. ___::- :_- -- :---- --- ----., ------ + -+--!- _;: -. = '_T_+ • -• "- .---+:=---=- ----_ -_-_-_-_-__._,---_ -:

-----------------------------------------------------------------------------------.-- ... ,---, .. • 7+ ++] :+ •. -+ , - - -- - --+ ----. . . . ... +. . •.• ..

*'"- I'''T- ?:... . t:_+______-,---_- -• - 4--•--.• --- • ... _-_ _ _ • - ...-

--I . .•., +- . . - . . . . ... . . . - .. . .. . ... .. . .. . .

i :'• :• •----•- -•-_. - +- --- ---- i::-• • +- -•:-• +---: --

-. .-- ,- -, . . -- . ... . .*.-T_.-•-,.. •_•--

••... .• -4-. ..-- •- + . .--- --, .....- - --.-. -- --- -------

__ ;__ __T__ -.. .' '- •'-----4'----'-" " . ... I-+'.-• - • - -*

,• ,,...-- - ,,...+L- t"" ... •" -i -+ +I .. ~. .~::: : 1-+"-'-+' --++-- .. + -+ • -.i•__z •__ - __.+• -;--* --- :::• -- • -+ --'j+_-- .- '• ---- '• -. ::•

-1 •- - -- - -" --. -'t.- a__ " -•---.--- -- - --...... -.... .. +.' -,l- . - -.

I .. . .• -- •-- ,-- .------ ... •--+,+ +I •,--:+ L,--

__.. ..... .__ __ __ _ -*- II -: ---

34.

- F - - ~ ~ ~ ~ .. .......... -. 4 .... a

__-7 - - -4 --- ----. - .

c0 a.- -. ~ .--- ---

3 -T - t-- :: - 7-± ~

14- :4 =:41=- :7z4=T

-f I .2B

0- 10 p20 . so 90 1S~ Rel -H -

° :,

|t|_

The •.bjec-:ive o. ".•i$ -.--or'_-: is io ob•.i.• zs rut-1 e.n •-_.-s•-•w. •

_-•o.•s•bie of •-e z•.¢derz:ed oxiO..•on of •!-_rainu.-n in the pr-_sence of --he curv

r 0-.

.

cri•-czl role o!eyea by •ler -•-r. .•-s = stev 1o•-•rds •ders•-v-';•r•z =mzsset es

=r•i•l ro!e. ii is vl•nn.e•. ;o c•r.•" out •.e ful!o•ring t•o " of ex•erz•_•_n•. = "•= °-.

r•icroscope, eleclron •f;'z•.•on, •.u• X-re.y ""-'* -- -•

size and Feilds z d•r•clian =•ern r•.•ie-al o• z•norvh•s :•.aSeri•s. !I

S"• e.•Lz: e r•zl•-°-

{Z! Che-•nic•l sr.,di=• •iil be -•_-e-de in •u e.Hort 1o " " -- ';--= the

zz=ount of•- i=-'-co=•,•'-'i--d in the •---x:•d•.•on .•-':•---•-" .. •-•,c_• • s•-•,•.• •.II be

-'.e•. • --'•dt oer_•use s• le •.• .... .= •..z':•.e.=-=- • •lso ooss-•ly ---•r•o-•e so•---=

S,•_rc•-v. z_•a•ea" -.n" --•e v..-o•nc," . •s iz ;s •orzne•. Tire exmc• o-o•e•ure to

Soe •o'Ao•ed- • De b•-sed on prelizninary • •ne-•< in •ich the prodec•.S•---•:11 be ]:e•ted •t I]O'C. for l• hours z•.d ".he •eig'-•-•• !oss .--i_'A! be de• ed-

• O=•=•-. .-:-•-='•: :•-:i--•, zn" w•_.i:• the .or•d•ct •-=AI be des!co-ted a• room te-•=•-•. -- -

rare, •6.'_I] --!so oe •, •ee o-•.

S-

m • 1 .... .. '

36-

Qiuanzit;a: ye rhaL nthe rate of ox--cation of alumininun in

o~ resence w! HI~, have been lite o wcure alur-Lnintnn A few Studies

!I ,ý c~r:ied out durine the neict cuarter on less nure alu=min-um and on

azuun-mz.a at!vcs- 'The C =,e.; "-fths will~ Wbe DCoezermin~ed ypelmnr

ItiS wc' tlat iron has a moi=Fate :-i a~. ozidation (or rusting)

-n h-:ghly inu-mid atm'-n ipheres - D-1--ring --he ;-ez! quarter oreliminary and

qualittive enienson iron will be be-u to-trin h a-eo

ofS~n 0! ~n zn h=-d--: !h~sn~c - re 1vresence of iva-rious metal sal:ts-

I4

3L~

L~D'-dA jack-sor. jr. *and -Heary Leidheiscr. jr..

"ý-ithh. Sixth and Seventh Qi.trvRenor~s 'to theArmy Chf-mical Center under CoziLract No-. DAIS-IGS-495- -_518, janua-ry 19, 1961. AprR 2. !961, and

2- D_ S_ Ca~rr and B_ L. -H arris. Soluti;ons ior 11a;minaingConstant _Rl"_r lndustri~u1 and Engineering

Chemistry. -41. 201.1( 19419).

L-ange's lAa.=SDoork -3f S h Ediftion, 1454..55(1952!0-

- -- nzue's HaxmAbook of Chemist-r. 9th BEd~ton. 14ZO-27

(196N

Vp