——
—.———
_’
__——
_——.—-
——
_—
—.
_—_—
-———I
_————
—_———
——
——
——
”

 

x Mmmzm m

mm 32% Lek fié‘ gag-w

W“,

"-t‘ -\-Qco-- a- J .
6

MM\ v-' '
.9. . ... '. .

p

 

 

' “.1. -

 

~
’ ‘ O
5 V-

u D
i. g
‘ 3-3—3335” ‘1!"- 3‘ '
. ‘.-‘.,t V. a -I .’|
. . 4. . ' .
o ,1) .5? _, "rm ,5;

U‘

‘ TH [if-Si
l

 

 

 

J / .mg. “the:

 

AN INVESTIGATION of the EFFECT

GRATN SIZE on DEEP DRAWTN

An Investigation of Effect of

Grain Size on Deep Drawing

Thesis
Submitted to the F culty
of
liich'g an State College
of Agriculture and Appliec Science
In Partial Fulfillment
of the
Requirements for a Degree
of
master of Science
3*».
Stuart EILEigglair

June, 1930.

ACKNOWLEDGMENTS
The writer wishes to express his

appreciation to Prof. H.E. Publow, under
whom this work was done, for his ever ready
assistance and suggestions.

.I also wish to express my appreciation
to Albert Schweizer and Milton H. Grams of
the MOtor Wheel Corp. for their assistance

in obtaining physical tests.

1.
INTRODUCTION
An Investigation of the Effect of

Grain Size on Deep Drawing.

The phase of cold working of steel that is en-
countered in deep drawing is a subject upon which thcre
has not been a great deal of research. It seemed that
it might be possible to find somt quality in steel
whereby a beginning might be had towards standardization.
It would then be possible for a company buying steel to
specify what physical properties as well as chemical
analysis the steel should have in order to give definite
properties on being cold worked.

The amount of investigation that would be necessary
to obtain data for such a standardization would be
greater than could be accomplished in this work, due to
lack of time and equipment. The phase that has been
chosen as a beginning is to determine the effect that
is produced by different grain sizes in deep drawing
steel.

This is of course only a step towards the goal,
but it seems entirely possible that companies should
be able to determine easily the properties which are
inherent in that steel and to know how far it may be
cold worked with safety. If, therefore this work
is continued where time and ecuipment allow, the

result should be gratifying.

2.

The experimental work consists mainly of a
series of heat treatments on a number of low
carbon steel samples having the same composition.

The samples were tested and observed after treat-
ment and the observations correlated to determine
what qualities had been produced and what their
use would be in actual operation.

Another experiment included the investigation
of a sample that had failed in practice. The
author endeavored to correct the fault and in so

doing determine that had caused the failure.

3.
Experimental Work I

The object of the eXperiment was to determine if
possible the effect of grain size on the deep drawing
properties of a low carbon steel.

If the effect of grain size is to be considered
it is then logical that an attempt be made to produce
as large a grain as possible and also as small as
possible. To do this twelve samples of steel having
the composition of carbon 0.22% and manganese 0.31%
were placed in a muffle furnace in a neutral atmos-
phere and heated to 19000 F. for one hour. It was
known from a previous work (Bull. No. 9, M.S.C.
Engineering Experiment Station) that this would pro-

duce a grain of nearly maximum size in the “as received"
pieces. Another group of "as received" pieces were
heated to 16500 F. for one hour, quenched in water and
drawned for one hour at 15900 F. This treatment pro-
duced an unsatisfactory result as far as reducing the
grain size was concerned, however, on testing the phy-
sical properties were improved. Due to the fact that
grain growth had occurred it appeared that the drawing
temperature had been too high. The pieces heat treated
with some "as received" samples were tested for Rockwell
hardness and for ductility on an Emerson Southworth
Hydralic Ductility machine.
The result of the ductility test is not a true

indication of the deep drawing oualities of the metal.

4.

This is evident in comparing the manner in vhich the
metal is distorted in the testing machine with that of
the presses used in the plant. The shape of the
metal that is cold worked is controlled by dies both
above and below the stock so that the Operation is
not one in which the metal undergoes a great tensile
strain, but the metal must have the property of
distortion without breaking. Witt the ductility
testing machine there is no die above the steel be-

ing tested, but the ball below is pushed upwards
distorting the test sample and acts as a die Fig.
11 shows a diagram of a test piece in the ductility
machine. The difference that would prevail between
the testing and the actual cold working on the press
is caused by there being no die above the piece so
that the metal receives a different type of distor-
tion than would be evident in actual practice due to
the pressure being increased until the test sample
is broken.

The observations that were taken in recording

the test were as follows: load at .250 inches de-
flection; deflection at maximum load; maximum deflection
and maximum load. The load at .250 inches deflection
is a rough measure of the hardness, but it cannot be
depended upon to give accurate results each time.
The deflection at maximum load is the most important
property to consider for through that value it is
possible to Judge how much depth of draw a certain

piece may be expected to withstand in practice without

Dag/“am ofa Par/x00 offlfe
Dad/#09 Mac/7M e

Def/£62700
‘ I na’ical‘ar

(Ila/oer 670/»;

///// 5:;

(Ila/oer (/0/77/9

“““

 

II"

 

 

1

 

 

\
/

 

 

 

///

Lawer Clam/o

A.

Lower (/am/o

 

L 00d fl/a/o/Ied

Hy. //

failure.

Tie type of fracture which occurs in using the
ductility tester is also an indication as to its cold
drawing properties. It is a desirable quality for
the distorted portion of the test piece to have a
smooth, fine texture on the exterior and that the
fracture may extend around the extended portion
paraIEfl with the base of the piece. The break should
not, however, be too near the t0p and extend entirely
around that portion as that would probably indicate
brittleness. The hot rolled "as received" stock pro-
duced a different appearance after testing than any of
the heat treated pieces. The break did not occur
alike each time, sometimes being around as found in
the heat treated pieces and sometimes across the top,
but in all cases the material became exceedingly thin
throughout the upper portion of the stock.

Figure 1 shows the type of break occurring in the
heat treated specimens. It is noticeable that the
upper portion has not become very thin and that in tne
region of the break the material has what might be
considered a “small neck”. Figure 2 shows a typical
"as received" test sample. In this case the sample

failed around the distorted portion, but the break
occurred as the heat treated sample. As far as
location is concerned the upper portion has become
uniformly thin throughout the whole upper surface.
‘Witk the heat treated stock the break usually appeared
as desired, parallel to the base, but the appearance

varied according to the grain size and the condition

of the grains.

' l

fheat tree.

 

a
I ~ .
r~ae.xu'

l‘rqg.¢

 

 

\ . .7;
f
LJ .1.
I .:
. ,,\
1 .
. .
.3
K
4!; O
x-
s. .~
.c.
\.‘I.
J
.5.)
0
’y
w. a
0

..1'(,A1~[;

J '.

'c'

 

 

 

 

The data
follows:

Heat
Treat.

Piece
No.

As Rec. Hot

rolled

1-12

23-32

35-42

51-53

54-56

63-65

66-68

78-80

81-83

84-85

88-89

19000
1 hr.
s.c.
1620O
W.Q.

D.l590°

16000

D.l310°

1610o
B.Q.

D.l300°

16100
B.Q.

13.1360o

16100
% hr.
s.c.

16200
B.Q.

13.14600

18500
8.0.

D.142OO

16500

taken on

Load @
.25 in.
Deflec.

10,000#
10,300#

9,800#

12,000#

11,200#

11,000#

10,600#

10,400#

10,000#

10,000#

% H.S.C.

1890o
s.c.

10,1oo#

R.H.1590O

1890O
s.c.

9,700#

the various pieces tested as

Max .
Defl.

.447
.375

.400

.435

.425

.415

.370

.420

.405

.420

.405

.400

Def.@
max.
Load

.315
.345

.360

.335

.370

.346

.342

.345

.370

.345

.332

.345

max.
Load B

Hardness

11,900#
12,000#

11,700#

14,000#

13,600#

13,000#

12,500#

11,800#

11,500#

11,700#

11,500#

11,500#

Rockwell

61
56

61

75

70

68

62

55

61

61

40

48

R.H.l500°
Nomeclature: S.C. - slow cool, D. - drawn, H. - hour
R.H. % reheat, W.Q. - water quench, B.Q. - brine quench

4.

 

 

ad ~o —.\.p ..

fi‘la' Us“; M“M‘V’§"“ ‘1- ~M on“ I
' l

.- w 'J— : ' - .
I .
.. .

Fig. 3. Fig. 6.
"As received" hot Heated to 1900°F.
rolled BLOCK. for one hour. Slow
x100. called.X100. I
_ ”Fig. 8. Fig. 15.
.Water Quenched from lOSJOF. Brine quenched from,.‘
‘Drawn at 15950E. X100. 16000F. Drawn at
"" 3‘ » ‘lSlOUF. x100.
. " ‘7 '

.; out a Lariat

.‘

.L': .rf..L '1.
.f" . “r. f V, , ~ , .I
‘ GJ-L laiL'Il L‘eiLUAiULJi, 'lej ‘1'

‘._r\.r“1’ .' ‘J ' " . ‘ V _ .‘
.uel. Lb... Jb nu. . .,

 

 

 

. \fi .-

. .nr'. -_. .... .9
.II ul‘.‘\1“.

 

 

 

 

 

 

 

 

 

cow

10

.n-c--." 10-F~_~I'F-. -- fl.‘ ‘wu- II. a— Q -—---—ll - .n.- a..-‘ ....--_I ‘

Fig. 4. ,
"As .received" piece. " f
. x500 . ' g

r
I

.5

i

5

E

i

i .
L...

--... -—"‘-‘ - . .' - ' C c Q I I. O I- o «I. I. In-“ I

O

I
S
to '
-II- _- .~,-.. .

 

 

 

 

 

 

 

 

 

 

«a», .

.- JO

 

 

 

 

 

.IF-q

 

 

11

 

 

      

.1 3. x e .
_ l... .
w. . .r
. 'c
.. L. .. e
.. - a. . y
a ..
l . . .. .0V 0 I .
. .. ... . .
O a . c u . a .9
r . . . v .
. "M I. Can“

.. rim! \ _ .1 . -.fl..v v...” .

  

Ii

.c.gifi
.fiocia "LSViSOSI HA"

X

C”

Is Is ."
. UUp

 

 

 

 

 

 

 

 

The resulting comparison of properties occurring

in the first three sets tested including the "as re-
ceived" pieces gave quite widely varying results, a
condition which is entirely an expected circumstance.
As will be noted, the maximum elongation of the "as
received" pieces is far greater than the heat treated
samples. This is a result of excessive stretching
causing a thin portion throughout the top. The greater
elongation is caused by the thinning of the piece at
the top, a condition which would be very undesirable
in actual practice on account of the loss in strength
that would be evident in a finished piece. The main
difference between the coarse and finer grained heat
treated test pieces is their exterior appearance. The
coarser grained pieces are inclined to cause a rough
surface which could not be tolerated in practice. The
differences in deflection at maximum load and hardness
is not great enough to be considered important so the
reason for rejecting the coarse grain will rest with
its rough exterior after cold working. In Figures3, 4,
and 5 are shown the "as received" stock at different
magnifications. Figure 3 shows the steel to be banded
to some extent, Figures4 and 5 show the condition of the
pearlite and Figure 6 shows the large grained sample

at 100x, while figure shows the same specimen at 500x.

The test pieces were cut through the portion pro-

Jecting caused by the ball in the testing machine.

These pieces were polished, etched, and photographed to

 

show several characteristics. In the "as received"
pieces figure 10 shows the result of cold working. The
elongation of grains is very apparent and in comparing
with figure 4 there seem to be but minor changes in the
atmearance of the ferrite and pearlite other than the
elongation of both. The band of ferrite does not appear
to have changed and that may be an answer to the question
as to why the thin portion appears across the top on the
"as received" stock and not on the heat treated pieces.
Figure 8 and figure 9 showing the stock which washeated
to 16200 F, quenched in water and drawn at 15900 F does
not have the banded ferrite, however, the pearlite seems
in this instance to have precipitated in bands and the
ferrite is fairly free of banded structure. This condi-
tion, in my opinion, would promote the possibility of a
thin portion occurring across the top asthe ferrite is
more ductile and has less strength than the pearlite,
therefore if these types of metals are deformed it

would be expected that the piece having ptntions that
were reasonably ductile extending throughout the piece
would for the same maximum load give much more elonga-
tion. The pearlite in the banded condition seems to

act as a reinforcment and when the break occurs there

is not the extending and reducing of area as is present
in preceeding sample, but the break occurs nearly simulta-
neous around the piece accompanied by less reduction in

thickness of the test sample

14

 

O \l .kiJ
'1 l i >1;-")-‘L:;JJJ{ i a
-. , L
1" " ‘
Qt‘JL V J a- 1 '1‘. g ‘ k“ ’L
'."‘.."
.LLk-a
.r z;
I «L I.__,—~ J
' ' ,, __ _.' .f‘" - r‘
L:>J‘.9-11J.U1. aura-J. : laifu

 

 

 

P i V d h
r t . . a
O l ' l l | d I .
a q l l . .. P
. c. I. I i_ LI 0 ‘ . -
~ . z . _ .. u. .. e
e .
- V .
a ‘I .
.
A _ s i . \\.
.. . 00 .3 .. . .
u.‘ v w n . . .2 r . . .1
I. x i . . 0 I! l~ h r v ~
0 a . s . c .4
1 N. .V . . ..
a I
. 4 . e .s . p.
. . . y
o u
u 4 . . . .. u a
\ l r \ I - .‘
p . . .
u. a . . . .
h .. . . . .
. I I D .
a o . n c!
a _ . . . u a
.0 . x . . D
I A

 

 

 

 

Figure 12 shows the large grains in the strained
portion. In figures 13 and 14 are shown the beginning
of fractures. Figure 13 shows the fracture in the
coarse grain in which the ferrite seems to flow into
the cracking portion. The pearlite located directly
in the crack has somewhat the same appearance as the
ferrite in the neighboring regions, but the pearlite
that is just removed from the disturbed region has no
sign of distortion in evidence. In figure 14 another
fracture is shown of a finer grained piece. The state-
ment that was made regarding the previous coarse
grained piece seems to apply in thisone also as what
pearlite there is, even though it does not appear in
the normal condition, is not.distorted and the ferrite
grains have been extended greatly flowing into and
towards the fracture.

It was evident after counting the grains that to
obtain small grains of minimum size a different heat
treatment was necessary. To obtain a smaller grain
a faster quench would tend to assist such.a condition
providing the correct temperature was used to draw back
to the normal state. Pieces 33 to 43 were heated to
16000 F. quenched in brine, reheated to 16000 F. and
again brine quenched. Some experimental draws were
then made to attempt to get the desirable grain size
characteristics along with a hardness that would be
practical to consider. This proved difficult to
accomplish. The remaining pieces were drawn at 13100F.

for 1% hours and furnace cooled producing a hardness

an

16

Fig. 10.

Showing distorted

"as race ived"

X500.

 

 

   
    

grain in

piece.

\
‘1

‘ . 4n fl? oHRO-M-

i
" o wanna—1g

‘. ‘ . _ , “7- ‘
t .. we 3»
s " ii ”rut/K ‘ 1 "F M #%
. . g: ' 313.;
' _ '_.;;-.. . y I; . , ~ , ' 1
I , ,3 ‘ . F}. I, ,. , . 5' ‘
F. i fl§§$ i“t {w
I
; Sho agfiistorte a‘rge ‘* 3
”4.5.1 _
I” . {5‘
‘wg-
‘I I ’ I
‘ braillso X5000
,i
I
as], ,\ :41:
.t'. , .
i”
3' " ‘
- . 3.1 5
° ' rent".
3 “ ';'\.- 74. 5 5"". - 'l‘vé‘ai‘22. I
‘4"; fl "’ ”t 7* 1-31,": ;£'t’ ‘ '
.. ,.'. ~56 v - ""2“
fl. _ : " D ' ‘ -" L‘ ii;
1:123“. ‘ ' ..; “4‘" "a?“ "
. ‘ ,gr?“ ‘Iifvfif' ' 91;
. .. .
;. ..'..’ O’I‘L" . - ,," .9. o
f f; 39?, 2: 04.? J
‘.3‘ , a . .
l _ ."
fist.“ 4. " . 4
4.”: r‘ n g - -s- 1-“ ~ Q 0...... . the o . ww‘» :‘Waé’é ‘- D' ’ J“"* " ' ‘ er 1

\4

J;

dLQI LSJILJaiL

I ‘r v- \(
okL-UJ‘. gall-AS‘JIL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

\

.ofi‘in‘ I. 00.....I.- 11..“‘.
a“ .....r #- .flf .. ._ .fiq .

   

c

  

HIV 1.: .

.ow.

 

:4-J ;;.i;.dcii£'
A hi Stujcflll s is

._ ‘ ‘— , .r fir-yl
'U‘JC‘L“; 1.3..1.).{_, :1 .A."

V)

i \

‘J ‘lO L‘EIJ 11....Llied. (3)11], 'L’..tJ.-"{Cli6-

Lenihig sail e mi studoeil

etc? .ieosiq

 

 

 

 

 

 

 

 

18.

of 73-75. The structure is shown in figures 15 and 16.
The results were not (esirable so a trial heat was made
of heating to 16000 F. for % hour and quenching in oil.
This produced a rockwell B. hardness of 81 plus which is
too high to consider and the piece which is shown in
figure 17 was not tested. A treatment then was tried
of heating to 15700 F. for 15 minutes, oil quenching

to 13000 F. where it was held for fifteen minutes and
slow cooled. This produced a Rockwell B hardness of
54, but the grains were larger than those found in the
"as received" pieces. Three pieces were then taken,
heated to 16000 F. for 10 minutes and brine ouenched
giving a Rockwell B hardness of 100 plus. Two of

the pieces were then reheated to 1600 F. for ten
,minutes and brine ouenched giving a Rockwell B hard-
ness of 111. One of the remaining pieces was again
reheated to 1600 for ten minutes and brine quenched,
this however did not materially change the hardness.
FigureslB, 19 and 20 show the photographs of these
pieces in the quenched state. Experimental draws
were taken on the three pieces to determine again

the treatment necessary to produce the desirable
results. Small pieces were cut from each of the

three ouenched pieces which are numbered 48A, 49A,

and 50A. These small pieces were all drawn at

13000 F. for 15 minutes and slow cooled. The hard-
ness on the single and triple quench wasthe same

or Rockwell B 63-68, so the single ouenched piece

was used for the remainder of the experimental heats.

19

 

'-

~¢ up“.-

17.

Fig.

011 quenched from

lGOOOF. X500.

fl

-l s.c--I. ‘II. -I‘

f

 

“I . "17- .VI .5151
“(I'll L:_;ii:)i'iéji.oil) saizi irilj"1'i Luna. sup £10

.QQ-ol" LLJI .C-(JcX {Shit-31:

z‘: I I}- -.'l.
L». .~.lu .Ll . '1’.

'—J

i.~,u.io.isup Siil'I‘J sLL-i'i‘ LLL'iJ. Laiionuw slautC

J.

_ ,. L;- , . .. . . "
.(vUCX O (wk—J1 ILLU.11 .OL'KJ}: or.“(-’0(\J|’-)£

 

 

 

 

 

.. ,1 I
x .. .wn‘

\. ..f
O

 

 

 

 

 

 

Figures 21, 22, and 25 show pieces after this treatment.

The next draw or pieces 485 and 480 were rejected
as the temperature recorded was questioned asto its
accuracy. The next draw chasen or piece 48D was heated
from 15500 F. to 15800 F. for 45 minutes and slow cooled.
At thispoint a strange phenomena was observed in etching
which nearly led to erroneous conclusions. It first
appeared that by regulating the drawing temperature
accurately that grainless steel might be produced as
is shown in figures 24, 25, 28 and 29. Upon further
investigation it was found to be an error in the etching
technique for by using a light etch the cementite could
be brought out without any indication of a grain boundry
whatsoever. It can be observed that the cementite
granules seem finer and more equally distributed in
the pieces that are drawn at 13500 F. or above than in
the pieces which are drawn at a lover temperature.
Figures 26, 27, 30 and 31 show the same pieces referred
to above only they are etched deeper.

Other experimental draws were made at 13500 F. on
48E., 1330-13400 F. on 4so,:134o-1550°F on 48G, 13300F.
on 481, 1290°F. for 1} hours on 48J and 1240°F. for 1
hour on 48K. From the results of these draws the.
temperatures of 1300°F and 13600F. were chosen. Pieces
51 to 54 were heated to ieoo°p,, brine quenched and
drawn at 1300°F. for % hour a:d.slow cooled. Figures

32 and 35 show the light and normal etch of these pieces.

It

 

Fir. 21.

t

i .

j Brine quenched from
i , .0 _

I 1000 F. Drawn at

lSOOOE. X500.

fi.‘ A,
r15. :0.

Triple brine-quenched

from 16000F. Drawn at lSOOUF.

X500.

 

 

.. ’ .« I nut-‘3 uq Q v;'073-~O¢‘_ov¢ -. .“ ~.~
\t‘ ‘. I: .' v't ~, _ «a
s' .. - wwww+
. m» *-«

. so .

a 4:

F15. 22.
Double brine quenched
from lbOOOF. Dravn at

isoo°F. xaoo

Fig. 54.

Brine quenched from

a- ._ ~- on
1600 b. Drawn at 1050 F.

to 15800F. light etch.

X100.

J.

UL

I A

1L)

.iiOJ

I

9

J

. ’_4
{3 'rr
V,}' 14:

Leno ....s;1r<-~
1

1".
.0

l
J». D'
' k.» "
1’4 “‘
V L L .a.

r:. k“ r
o A --
- .V
I Q v . A‘
.< - .4
. in.
O _} - -

41.‘I'..‘:3.0~(:

,il .5;

r
I

say:

L. ,. -
L: 001

U -‘ . .-
(itsi C3

. (25.1.?

{.4
. .

L p . _
L:L-’C;.L 3‘)

ni'i 13.0.;st 5.1113

- \t‘.’ r b ' '
38 “JMLL .u vLJI

.Kluié}' .t’EULK‘gi

.‘ \I» ’ Cl h. . - f
:1..’:.li .‘\ LL ‘1. “LII.

 

 

 

 

 

 

 

 

 

 

 

‘Vo‘- .\

light etch- K500”,

:Fig. 20.

.
up.- “- v "'

Brine quenched from.

16000F; Drawn at

135003. LO 153093.

.
n--‘é-L ~ . ivu‘w iw‘paw- “4 rm- ..£A_)AJ'~ -"'

Fig. 27.
Brine quenched from
16000F. Drawn at
1550°F to 138QUF.

Deep etch. X500. 1

- “van-.0 I-l' . . ‘- --’ t

a. m ”“14. unm-nrq ve—vp-e

PM I “nu—u. I-.1-
'-

1‘15. 46.
Brine quenched from
loOuOF. Drawn at isoQOF.
to lbddoF. Deep etch.
X100.
,w m v.1-li___.,-_wi ,1 _a-_h,11
t
Fig. 26. l
Brine quenched from 3

1600°F. Dratn at 2
,15aoor. light etch.
1100."

4"-

.xMLa-‘k'.: ¢_‘x 0--

. -"4‘ . ' :.."‘ V " A.‘ ,' ’r ‘ r ‘ .‘ "' a. ' I. ~ 3 ‘ ' ‘1
. .KJ ‘- L 1.3....x.) .Al.) L}; \1 -‘ —~ 1‘. Lak» l l lchlld In: ‘Ji ‘3“.1. ’1 l

' l .. . . m “ L’ L . . - . rib z ‘
cups. as. _;'/.:'l.‘. . ~ t i um 11 {:3'1 - . *L LOU]:

L

,t “(mi 93 .- heel c. .hotcci

‘ . - v . 1; . ~.— "7....
.tci; . MC; .nSJS chair
' _ v rv
. ‘ V‘ . <—-- 'L o\ ‘ c -;\«L h

J. '11 {.:_'i‘.‘.'.);iiiu;.' 5.111; w "KI I.:‘:7‘l'i1)iii.‘UiJ sal'IEL
J :3 [I .310 . F; 00.31 3‘ 6 i1 ‘.-’j_;'1f [up CCJI
11 .1 C401 .Ztthoi eJ hctcci

.001? .Uth .HOJs qas(

 

 

 

Hr I01... in .

. I

",c.

. -.
.‘ .._-
. n. ‘3'
.r'
1‘

           
        

 

 

  

 

\d
ls
D. I
on 0.. - v.I.v
. . .11.. .. . . ... . , ..
. . .....w . . ..w..a....r....« 4.3.4. . .. . ..
... u . I . 9|. . .... . .‘.. n ‘ ’0-A . I
.. ... .\..l1:\1..~|.1y.~tf. 1‘: LJ. 5! ...a”. anal-(FAWN... . . .i ..r . u
: . _ . .. ...}... _ 3....-- 13.3.... ...). ... st. T-..
. . r . .1: c.. ... ... . ... t. .. _ .w .. . s ..
.. y . . 1.: ..r..- N. . ... en. ... r, I {a .b. . .
. . .. , V... . 1...... ....l..J..... W..\Ila ...Kiqi‘.u.i.1\\.u.,ru5 Je..?...).. ..I .
. ,. L 1.. .. . . .o’wl Inla.c . .1... .Ww.u..o x-n|..vv..l\ .ta ...-[..-u. .. .. 05:
. . . . .22.... ..., .. . ... .1... . .. . ..... ...... . .. ....
t A. \ .. ..-. ... ..... (£53.12 ..v. s s. 7...”. . . ...... ......“ ... ..... . ..4 I ,
. (0 . .AI-Ptul . .. ... \ .\1.‘.... a... : ... ..vaufihp 4.. ...... Rah .’ .. ....J ..1510 . . v .4. 1...... . .
. ....1 Ir, . .. .3 m. .‘. 1va J...... ....fi. ..... bul.~.~._ ......... .. .H.. , ...... .....
. . Du‘ . . . a... c. ..Q. .JA... .. .v..r~¢\\-.f t . 11.. .. . . . .
I ‘ n . . r . l..nr...00v\W. . .n.$ul .6.‘..\v~ I .4111. . v\. 5L . .. .. a u.
...- . . #90. {..211 .r. . ...: i. ... .... ... .
rt lit. .. ...... :1... ... .1..\uc .....ov . ... x. I .....Ao; .1. oru.».\; .1
t l . . .. . ... ., .... .
.. 3.13.... M4. a. ... a 3).. ...... ...: . 7.1....“ 5.904.... . .n . ..
. . k. ; . c. 4 ... ..I .j. N I.
10.; 0.....1 \. .15..“- L..u.m.... .|..n....... . -..... 1‘3. .- .bJ ..| . ..\.. u on u‘ .b.»
\l .... . ..I.4 -. T..: . l . .. .9... .. .. ....\ .. . ..
. ...... . . .. .....(v . .. .. ... ~ .
w.»- kosa..~v.‘k...:. A... ...c.. . .19.. ......u . .. $.14!
Er. ....Ir. are? . 5...... f. ..
. . . it... .... .
I: .5.

 

 

 

 

 

 

 

 

 

 

I.. - *
o

- - ...-"H'.’ ‘ ..‘a )— ' i.
LII-- ‘ 5....“ Jule-L..- M-L-—-D—" nit-‘1‘

 

a3

Fig. 290 .2

Brine Luenche¢fnon§

lbuooF. Drawn at '

§

”é“...

1350013 nghtl- neigh-
' ... 7. . . .‘-_:3 I T
beQ".. ..I IL..." ,‘r a‘. ' ‘T ":1
h" .u (1.. . f; _ ' ’. .t ' '. u.

I I ‘- ' ' ‘ ~

g
‘ :-
fl“ '-’

 

Fig. 50.
Brine quenched from :
1600°F. Drawn at
lBSOOF. Deep etch.
X100.

f”“‘"“"'""‘ Fig: 32."
i Brine quenched fromn:
3 léaooF. Drawn at-lSOOOF.

w— w‘ 'MI-F m u to

 

‘-
. b
3'.— ‘- “~‘u-.vum-.-uw -...

. x :J o C L T . ta-‘ . ' I i
. L13 LBdOutlg;5Lgin vaTI LSHOung :MLFIi
{J {‘3 ii .FJ'LC. .r'. Lu .JJ. .7 f] ;1 115'1 . {L \ \. J.L

.oua ;336 .ZVCC$£ .LQJe ong.I .TLOCCI

.mq .pifi .IE .gxfi
.....L."I'i 1.53.10-13.11) 8.3.1 11 L“ "1'1 Lenonsup 9.11151
1"(le ' ‘. ---- -. T I' (J‘ V- a ~- ‘\I' ’ r ~-\ V I‘
.: upul J. “IS-L .; ..Ji 3; u’b.( .LCULJI
\ " V- -.. .. - -. - .. ,. . ‘ (’ ,'.
.UUbX .HQJB JAU.I .muJb :3;C .E Lbbl

0 {J\_ (I):

 

 

 

 

WT ., .2“'J‘I v“. .. .
' "7373‘ 'r‘"“.-‘.vr?z$" & '-
k? "K n “.'.‘. ,1
...}... , 4t hf?“

   
   
      

C ‘ I ".n-("

+ . "L'J‘"I::"‘,

I. Q q, .1“
k". . '

    

 

 

 

 

 

 

 

 

 

 

 

 

.113»! (View. wv

 

 

 

 

 

 

 

 

2‘7”“ 12*.” , i
i
2 i
313.,33. . §

0

wwwqo -’r~...~v.a'—..P~ _-.—.—.-~.~..‘...-

FT“

 

“Deep etch. X000.

Brine quenched from§
16000F.  Drawn at 13000F.

L 0

v .
‘- " Q-fln-jih-s“-. an;

J‘..'V1_ I > ‘ . 3| '\ " '

.‘ I - .l . -
= «.0. . r in 2583:;u huts-.3

 

Fig. 36.

Brine quenched from

 

lbOOOF. Drawnat'isetor.

I
2 . .;
2 Light etch. X500. ;
a . :
3! .
i

24

-vk o '

Fig. 30.
Brine quenched from

lcOOOF. Drawn at 13600F.

;.Light etch. x100.

r! 1"“ f ‘-
0

~ -..—“h- J- -*

Fig. 57.
Brine quenched from
16000F. Drawn at 13600F.

Deep etch. X500.

‘-
”...,
w .
atlx.’ ‘1.

.1.Ui1:'.;;JJ-J;J lex‘j.

, 1 (J '
I p ( ~
l ‘ ’ \ | l
A A 4 J. - 0 .4 v ._/ -J

.a.-<.,.17 .3013 J..._,11

(JR K
UJ‘QI 3.3

.C'

LadOflvUp abii;
_ L. ,
11.34516 .'b. L U .11

QQY' JiOJS tbaeC

(IL

[L

...; ‘L'i

sakL‘.l'1

L453]; 3

Luuoueuw euitfl

\.
A.

11.4".5'1C .9.“ up .)I

,xh’... .11333 Li‘JSQ

L311L).muy 3.41:1

\v .50 V r .
;n1J..I( .d cL WI

 

a o
\‘
.
w I I
o , .
.-
u I
, \ .
A . .
_ d
. .o c.
S I
. .-
\
C u
n

.s»
-..»

 

 

 

 

 

 

 

 

 

 

 

 

25.

Figure 54 shows a portion which has been distorted.
Pieces 54 to 56 were heated to 1600°F., brine

quenched and drawn at 1360 for 45 minutes followed by
a slow cool. From a study of the test results on
page it can be seen that this treatment produced
the most desirable results for cold drawing. The
metal is harder in thisstate than it is in the "as
received" state, but its drawing properties are better
as far as ability to be distorted and other properties.
It merely means that stronger presses might have to be
used and the metal would be much harder on leaving the
presses, a feature which is usually very desirable.
Figures 35, 36 and 37 show this steel under various
conditions.

The feature desired at this stage was to produce

results of the above by one heat treatment alone.
Pieces 63 to 66 were heated to 1610°F. for one-half
hour and furnace cooled. This produced physical
prOperties that were desirable, but grain growth

has commencedas shown in figure 38, causing a grain
size that isin excess of that desired.

Three pieces 78 to 81 were then heated to 18500F.
for two hours. It was then slow cooled to 11900F. or
just below the Arl, held for 15 minutes and then re-

heated to 14300F. for 15 minutes and slow cooled.
Thisgrain size was too large as shown in figure 59,
although the physical tests were desirable. The
pieces 81 to 84 were then heated to 16500F for 5 hour

£6

315' 05' , Fig. 39., i .;

.Heated to lLlOOF. ’ _ Heated to ldbuQF. 9 f

f hr. and 810W~ ‘ , hr. Slow cooled to 11900
cooled. X100. 1 - W. Reheated to leZO3E,

ani slow cooled; X100,

{‘0

Flé. a0, fl¢. 4Q.

Heated to 163003 Criminal of the stock
... ... ._- . ..vi U

— r,_" '— --

3; hrs; and Slow ‘ i which would not draw.
a r. .

cooled. K100. ‘ ? Xioo.

.90- .m- iv ‘1.”

If
\_I t,

‘\
It ‘J ,
. l

p .A \~ bx k-‘J‘ ..'~. :3” 't...

r' . ‘ ’ n r

Lu .‘3.LL,C:) IUL‘: ,1
r ~- 5 r

- .L Lu L17». )‘T‘ILQJL .

L.‘ g E ;L(.. (ii) I i. i. J. Li

..‘Y 7 .L .L
33 and Lo L;H.Vll
‘1 I- ‘ '. r' w -
:4.» \J(.i hiuv’f lit)--.n.

.idv—L

:‘xlr

 

”1‘

it.

 

 

 

 

W1, -. 5"
9°ch2:..¢..-5¥

     
   

 

 

 

 

.r
\

 

 

 

 

 

 

2'7

...-......” '9 .‘R I I” f -' Q I I ‘< ' .... .5 1

 

Fig. 48.
. :Briné quenched from 161003.
f ' Drawn at 130003. x500.

 

b

'
0
LA— 9! Own-'0 ... -- "' '5 ‘ -‘ ""I" 0 '- 0th- v-bd-.......w..-.._,_.~_ ____._ I ___'-
I

 

.1

FL'

f; L. r

\l

" 2‘)
. Li‘k/‘Jl’

.rrn

‘ J;

(J

L4 _L'_ ; . ' -,
JJQJ lCJwLi» gilllllk-ln

it)“; .-;'1'. 3.4;; 1,197 1‘;

1.1L Ti

. ..‘
o ('L'KJJ‘I

,. rs

.\/t) .¢)ir‘_

’,.e-.1i:);.9up emu

L

I

t.

A.) m. _
.1 L051 J8 hfifiTC

 

 

.

.\A ‘. ....

...7 ‘.YC .
:.

A O. .s \ .\
\F.W \‘FN‘.

 

~ .\. v» .N ..‘I .

.s. ..

 

 

and slow cooled resulting in physiczl properties that
.were right, but a grain size again too large for a
desirable.
'The next heat was run endeavoring to obtain a
smaller grain through heat treatment alone. Pieces
84 and 85 were heated to 18900F. for 2% hours and slow
cooled. The photograph is shown in figure 40. Pieces
88 and 89_received the same as 84 and 85 except that
they were drawn at 15000F. There isvery little
difference in the physical tests and the grain size
differed only slightly. It seemed that by heat treat-
ment alone without quenching a smaller grain could not
be obtained.
In the figures 41, 42 and 43 are the curves showing
the relation between grain size and the various physical

tests. The pieces are designated by the numbers on the

curves as follow:

1 -- Piece No. 7 5 -- Piece No. 67
2 __ H II 81 6 -- II I! 51
3 -5. ll II 24 7 -_ N I! 53
4 -- " " A.R.

The curve shown in figure 42 showing the relation

between depth of draw at maximum load and grain size

illustrates that through heat treatment the characteris-
tic of draw depth is improved over that of the hot

rolkad "as received" stock and with the heat treated
pieces the smaller grain demonstnated qualities some-

what better than the larger.

 

Def/echo” /'/7 I fiche;

390

.360

.3 70

".360

.350

.340

.350

.320

5M0

.300

.290

 

 

2;. 9

/? e /01‘/‘on Ae/fiaxeen Bap/)9 01(0de of
”70]. Load cf 6f4/0 .3729 0.5"

09/29/777 Med 0/7 an Emery foa/Zwar/A
lfibcfiflfi'/%myflhe

0%

llllu'l I ||

2 4 6 8
6/27/77; “ ThouaandJ/oer J7. mm.

Fig. 41

50

Rte/027m befweefl 670m 6719 &
P701. 1 add a: Defer/77 Med 0/) 4/7

 

 

 

E5. _-__ [me/7 Jaufbworl‘fi Dw/x/xp/ ”acme.
§
g /4
§
§ /3 — ‘0
E
'\ /z

// l l l l l l l 'J

0 2 4 6 ‘5

Grown" 77700.:0/70’5 per 5y mm

Fig. 42.

fie/af/oo be/n/éen Gram J/ze &
load 0/ c7 flap/)5 of firm/V of .25 0
M. our De/évrM/oeo’ 0/) 0/7 [/77 er y
dbl/7% 14/0/72 0 ucfi/xfi/ Mac/7x773.

a,
I

 

Thai/sands Ma: Load
\ \
\ m
l

L l l I l 1 ll

2 4 6 <3
G/‘a/na- Thoma/7d; per 6‘7. mm.

B

 

<0
C)

_Fig. 43.

51.

In figure 42 giving the relation between grain
.size and maximum load the grain size seems to be a
direct indication of its prOperties regardless as
to whether it is heat treated or not. There is a-
small gradual rise in the maximum load from the
larger to the smaller grains.

Figure 43 shows a curve very similar to figure
42 except that the "as received" piece takes a slight

change in position relative to the other points.

C»)
F
o

COKCLUSTON

In drawing conclusions from the work done the
curves in figures 41, 42 and 43 are the best indica-
tions of the results obtained.

The most important relation in consideration of
the cold working prOperties isfound in figure 41. The
maximum deflection is plotted in reference to the grain
size and here is founda rather uneXpected quality as
there is comparatively little difference between the
maximum deflection for the different grain sizes in
the samples that were heat treated not considering the
hot rolled "as received" stock as heat treated pieces.
In first considering the pieces that were just heat
treated without any quench it was found that the grains
had all atained some growth over that of the hot rolled
"as received" stock and all the grain sizes ranged at
less than 1000 grains per square m. m. The deflection

in all cases was found to be very similar, which is as
should be considering the comparatively little difference
in the heat treatment which they received.

The remaining pieces all received a quench in vary-
ing media and were then drawn to or near a normal condi-
tion and in these is found some varying results in the
deflection at maximum load for the different grain sizes,
but it isevident that there is a slight general rise as
the grains become smaller.

The hot rolled "as received" stock has a value so

far below the pieces referred to that it was not even

placed on the curve. The ability of a piece to with-
stand cold working is evidently effected to a great
extent by the condition of strain it is in. In the
heat treated pieces the condition present would in all
cases be less strained than would be found in the hot
rolled state. This condition seems an explanation as
to the reason for the very low value of the hot rolled
stock shown in figure 41. It seems entirely reasonable
not to expect steel in a strained condition to withstand
the deformation that steel in an annealed state will.

It is found that the appearance of the draw does
not change to a great extent after the grain size has
reached approximately three thousand per square m.m.
and it may have that smooth fine appearance somewhat b
below this size.

The curve shown in figure 42 illustrates the
relation between grain size and the load at a deforma-
tion of 0.250 inch s. This curve showing a fairly
regular rise in load as the grain diminishes can
hardly be assumed to be an effect produced by grain
size alone due to the smalkar grains being produced
through the quenching and drawing back towards the
normal state. In considtring the grains above four
thousand per square m.m. there is a fiendency for the
pieces to still contain some indication of the quenching
treatment. As has been stated previously these values
are an approximate indication of the hardness in most
cases and as would be expected, the hardness is higher

on pieces which have had a lower draw.

The curve shown in figure 43 showing the relation
between the maximum load and grain size is somewhat
similar to the preceding curve, however, the rise is
more gradual. It seems, nevertheless, another case
where an increase in hardness has raised its resiStance
to deformation for it was found in the sample that the
small grain gave a greater Rockwell B value.

The hardness on all the test pieces regardless of
heat treatment gave a higher value after cold working.
The pieces were ground off to form a slight flat portion
at the top of the strained region and the hardness in
all cases was found to ninety plus Rockwell B. This
hardness is not a duplicate of what conditions would
prevail in an actual deep drawing cold working operation
as the piece has been strained to the point of fracture,
but it is an indication that all the heat treated pieces
will harden to some extent after receiving cold work.

It seems obvious from the curves that grain size
is a factor in the improving of deep drawing qualities,
but the heat treatment necessary to obtain the various
grain sizes isalso a large factor in the improved

qualities over that of the hot rolled state.

Experimental Work II

This experiment deals with a steel that would
not draw and the object was to determine the cause
of its condition and attempt to correct the fault.

The original stock, which had an analysis of
carbon 0.24% and manganese 0.60% was tested on the
ductility machine which indicated its deflection
only 0.210 inches at maximum load, which was 14,000
pounds. The Rockwell B hardness was 81 so there
appeared from the physical tests to be a number of
corrections to be made.

Photographs shown in figure 44 and 45 were taken
of the original stock. In figure 44 is shown the
severely banded structure and in figure 45 is seen
banded structure is pearlite which seems to be drawn
out into threads.

The most desirable method of correcting this

defective steel is of course by one heat alone. It
was not possible to accomplish this as is shown by

the following information.

The following data gives the heat treatment and

the results of physical tests on the various pieces:

 

 

Piece No. Heat Load @ Deflec. max. MEX Rock.

Treatment .250 in. @ max. Defl. Load
Def 1 er: . Load T.-

Original .210" .255- 14,000# 81

Ne1 1380°%H 15,000# .250" .290" 15,100# 79
s.c.

NG2 1908043. 14,300# .260" .310" 15,850# 71
U. 0

N03 16100 B.Q. 14,900# .270" .325" 15,800# 76
14600 s.c.

NG4 10003 s.c. 13,800# .320" .360" 15,500# 61
1430 8.0.

NG5 19000 s.c. 15,800# .535" .430" 17,65d# 75
13000 s.c.

Nomeclature: H - hour, S.C.- slow cooled, B.Q - brine

quenched.

From the above data it is evident that the defect

must be of a serious nature when such varied and vigorous

treatment was necessary to produce qualities that would

cold draw.

With the piece N04 shown in figure 46 the

qualities are very nearly what a piece should be except

that the deflections are not as great as are in a

normal piece and the strength seems extremely high.

The strength might be desirable in the dies of a press,

but the author is of the Opinion that the high strength

would cause great distortion to the stock due to the

resistance that it would offer to being shaped.

The

piece N05 shown in figure 47 hasthe qualities of de-

flection greater than the preceding piece, but the same

_. ‘V m;——-—-;

 

Fig. 4t. ‘ 7 Fig. 47.
'Heatei to lQOOOF. ; Heated to lQOOUF. Slow
Slow cooled. Re- i { cooled. Reheated to I
heated to 145063. 2 isoour. Slow cooled. ,
slow'ogoled. X100. & X100. 5

Fig.'45’
"As received" stock that

would not draw. X500.

.‘-'J'n.'r-. ~ -.'

o _ .Maq. 5.1“ [v

"' “‘ ' «an-‘amn-v M:. _-

r L- ‘f'

.' \l\ _54.

afif‘

.\\' ,-hu—n
LL;

3 C :1

.{1 \
'- C...
, i to

II :‘J C N

J" " ir':

(.21 OJ led Bali

'-

.beltca N018

new". c J iaJ‘Jaii

 

 
      

   
  
  

.r‘.

        

 

 

 

 

 

 

 

 

 

 

38.

question enters as to what effect the high strength,
and in this case the high hardness, would have when
placed between two dies instead of one as is found in'
the ductility machine. ‘

There seems to be two, perhaps thrte factors, that
might be the cause Of the condition Of this steel. The
manganese content might have an effect in producing the
'hardness as it is on the uppfr limit allowed in cold
drawing, but a more logical and probable reason is that
during the hot rolling Operation the temperature was
allowed to fall too low. Another factor that had some

bearing is the presence of slag. In figure 45 the
portions that are drawn out thread-like are slag particles
which would also be undesirable, especially when found

in the condition shown in the photograph.

If the piece had been hot rolled under favorable
conditions it is the author's Opinion that the stock
would have given fairly satisfactory results on cold
regardless of the presence of an excess of slag and
the manganese being on the upper limit, but in con-
sideration of the eXperimental heats tried on the
steel "as received" it seems evident that there is

no treatment except hot rolling which may be given

this steel that would be economically advisable.

l.

3.

6.

03
t0
0

Bibliography and Reference List.

S. C. Spaulding., - "Effect Of Reheating on Cold
Drawn Bars" Trans. A.S.S.T. 9 page 685-707 (1926)

G. T. Beilby, - "The Hard and Soft State in Metals"
J. Inst. Metals. No. II page 5 (1911)

Jeffries, "Grain Growth Phenomena in Metals"
Amer. Inst. Min. Eng. 56 page 571, 1916.

J. A. Van Den Broek, - The Effects Of Cold Working
on the Elastic Properties Of Steel" Iron Steel
Inst. Vol. 9, & Engineering July 1918.

H. M. Howe, - "Grain Growth".
Amer. Inst. Min. Eng. 56 page 582; 1916.

M. S. thesis of J. W. Percy, "Grain Growth of Low
Carbon Steel" 1926.

Grain Growth in Low Carbon Steel, H. L. Publow and
L. J. Waldron,Bull. #9 Mich. Eng. Exp. Station 1927.

M. S. thesis of L. J. Waldron, "Grain Growth and
Refinement in Hypo-Eutectoid Steels. 1928.

A Study in the Rate of Grain Growth in Low Carbon
Steel, H. L. Publow and S. E. Sinclair, Bull. #29

Mich. Eng. Exp. Station, 1930.

 

mnjmsAN STATE wumnswv LtBRLRIES
;

”"1 “if“; I i'W’ W! !
‘7 5M 5) fi’"r"i
129' 03174 9'07

3

M
51' “
l; ‘
3 2

 

...

—.—~.V._‘