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The psychology of Froebel's play-gifts online

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Held at Atlantic City, New Jersey
June 26-29, 1917



Office of the SMreUryTreatnrcr, University of PeniisylvanUi, PhlUdclphU, Pa.



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Entered acoording to Aet of ConcreH by the

AioniOAX SoomT fob Tanorb Matbbials,

in the ofBoe ot the Librarian of Consreea. at Waahington.

Tha O ooh fy ia not req^onaiblek aa a body, for the atatementa and ofiinkna
advaneed in tUa imblication

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Ferrous Metals. p^^b

Topical Discussioii on the R61e of the Several Alloying Elements in the

Alloy Steels 5

Manganese — ^Henry M. Howe 5

Nickel— R. R. Abbott 9

Silicon— W. E. Ruder 15

Vanadium — G. L. Norris 20

Chrome Vanadiimi — ^F. J. Griffiths 33

General Discussion 45

Annealing Temperatures and Grain Growth — D. J. McAdam, Jr 58

Discussion 75

Some Applications of Magnetic Analysis to the Study of Steel Products —

Charte W. Burrows 87

Discussion 105

Non-Ferrous Metals.

Hardness of Hard-Drawn Copper — E. H. Peirce 1 14

Discussion 122

Electrolytic Determination of Tin on Tinned Copper Wire — G. G. Grower 129

Discussion 153

Light vs. Heavy Reductions in Cold Working Brass — W. Reuben Webster 156

Discussion 162

Testing of Sheet Brass— C. H. Davis 164

Discussion 199

Interior Surface Defects on Brass Condenser Tubes as a Cause of Corrosion

— W. Reuben Webster 204

Inspection of Brass and Bronze — ^Alfred D. Flinn and Ernst Jonson 212

Discussion 224

Cement, Concrete and Ceramics.

High-Silica Portland Cement— A. W. K. Billings 239

Discussion 254

Apparent Specific Gravity of Non-Horapgeneous Fine Aggregates —

A. S. Rea 256

Properties of Cement-Lime-Sand Mortars — ^Warren E. Emley 261

Discussion 273

Economical Proportions for Portland-Cement Mortars and Concretes

—J. A. Kitts 279

Discussion 295

Effects of Grading of Sands and Consistency of Mix upon the Strength of

Plain and Reinforced Concrete — L. N. Edwards 301

Discussion 358


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4 Contents.

Effect of Rate of Application of Load on the Compressive Strength of

Concrete — D. A. Abrams 364

Discussion 375

Tests of Concrete Slabs to Determine the Effect of Removing Excess

Water Used in Mixing — ^A. N. Johnson 37S.

Discussion 385

Tests of Concrete Road Aggregates — ^J. P. Nash 394

Discussion 417

Comparison of Heat-Insulating Properties of Materials Used in Pire-

Resistive Construction — W. A. Hull 422

Discussion 443

Failure of a 30-in. Tile Drain at Albert Lea, Minnesota— R. W. Crum . . 453

Discussion 464

Suggested Improvements in the Manufacture of Silica Brick — C. E.

Nesbitt and M. L. Bell 467

Discussion 483

Miscellaneous Materials: Preservative Coatings, etc

Optical Properties and Theory of Color of Pigments and Paints — H. E.

Merwin 494

Discussion 527

Metal Primer Testsr- H. A. Gardner 531

Discussion 539

Determination of Absolute Viscosity by the Saybolt Universal and

Engler Viscosimeters— Winslow H. Herschel 551

Discussion 569

Effect of Controllable Variables on the Toughness Test for Rock— F. H.

Jackson, Jr 571

Discussion 586

Testing Apparatus and Metliods of Testing.

Rapid Semi-Autographic Tests for Determining the Proportional Limit

— H. F. Moore 589

Discussion 596

An Alternating Torsion Testing Machine— D. J. McAdam, Jr 599

A New Consistency Tester for Viscous Liquid Bituminous Materials

—Provost Hubbard and P. P. Pritchard 603

Discussion 621

Method for Studying the Effects of Temperature upon the Physical

Condition of Asphalts, Waxes, etc.^. A. Capp and F. A. Hull 627

Discussbn. 635

Distribution of Pressures through Earth Fills— A. T. Goldbeck 640

Discussion 655

Subject Index 662

Author Index 669

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THE ROLE of manganese.
By Henry M. Howe.

Passing by the deoxidizing and desulfurizing effect of
manganese as foreign to our present piupose, its effect on the
mechanical properties of the steel seems to me in the last analysis
due primarily to its retarding action both on the transformations
and on the coalescence of the micro-constituents into progres-
sively coarser masses, which while increasing the ductility
lessens the cohesion in general, including the hardness and the
elastic limit, and thus lessens the effective strength.

We may consider the action of manganese first in Hadfield's
manganese steel, containing about 12 per cent of manganese,
and second in carbon steel, in which the proportion of manganese
rarely exceeds 1.50 per cent.

Before considering the retarding of the transformations
by manganese let us refresh om* memory as to these transforma-
tions, and as to the three prominent states of steel, between
which they play, (l) the common low- temperature alpha or
pearUtic state, (2) the high-temperature or non-magnetic aus-
tenite state into which the metal passes spontaneously when
heated up through the transformation range, say 725 to 900° C,
Acl-Ac3, and (3) the intermediate or martensitic state, in which
carbon steel is caught in transit from the austenite to the pearlite
state by means of a rapid cooling, as for instance on hardening
by quenching small pieces in water. The alpha state is magnetic
and relatively soft and ductile, as in annealed carbon steel;


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6 Topical Discussion on Alloy Steels.

the intermediate or martensitic state is magnetic, hard, and
brittle as in hardened steel; while the non-magnetic high tem-
perature or austenitic state when preserved in the cold, as in
manganese steel, combines great ductility with hardness of a
peculiar kind to which I will refer shortly.

In carbon steel this transformation is so rapid that it occurs
to a very marked degree even in the water quenching of thin
pieces, as is familiar to us in the fact that when this steel is
made non-magnetic and austentic by heating say to 900° C,
and is then quenched in water, it transforms as far as the mag-
netic, hard, brittle, martensitic state of common hardened
steel even in this rapid cooling.

Most of the alloying elements, and notably carbon, man-
ganese, and nickel, retard this transformation greatly. Thus
2 per cent of manganese plus 2 per cent of carbon retard it so
that in the water quenching of thin pieces the austenite state
is preserved. With 5 to 7 per cent of manganese it is so slow
that even in air cooling it goes only as far as the intermediate
martensitic state. Hence the brittleness of these steels of
intermediate manganese content. With say 12 per cent of
manganese the transformation is so sluggish that the austenitic
state is preserved even through a common slow cooUng. The
water-quenching of manganese steel in current manufacture
is not to prevent the loss of the austenitic state, but to suppress
the precipitation of the iron-manganese carbide, cementite,
which woidd ocair during slow cooling. The broad plates of
this cementite would embrittle the mass by forming partings
of low cohesion. It is derived from the large carbon content
of the ferro-manganese used, the cheapest source of manganese.
Carbon-free manganese steel should not need quenching.

The industrial value of this manganiferous austenite or
manganese steel seems to be due to its combination of great
ductility with great effective hardness. I say effective hard-
ness, because initially it is rather soft. My own experiments^
indicate that the Brinell hardness of an undeformed specimen
is only 125, or that of steel of about 0.22 per cent of carbon when
annealed, that of ultra low-carbon steel being about 75. But
the hardness increases very greatly on the slightest deforma-

> ''The Metallography of Sted aad Cast Iron," p. 464, 1916. '

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Howe on the RAle of Manganese. 7

tion. Even that incidental to the Brinell test increases the
observed Brinell hardness to 223 easily, or to that of 0.60-per-
cent carbon steel when annealed.

This hardening under deformation is one of the first things
that forces itself on the user of this material. The first strokes
of the hack saw cut it rather easily, but the defom^ation thus
set up in the path of the saw qui(±ly causes such hardness as
to bring the sawing to an abrupt end, thus giving the absolutely
false impression that the material has a soft skin. This harden-
ing causes the apparently contradictory combination of effective
hardness with very low proportional limit, even as low as 28,250
lb. per sq. in. The proportional limit represents the cohesion
of the imdeformed material, the effective hardness represents
the cohesion as exaggerated by the deformation incidental to
service. In the same way the act of tensile rupture may increase
the Brinell hardness to 540,* or that of about '0.50-per-cent
carbon steel when hardened.

The surface of the jaw of a manganese-steel rock crusher,
deforming under the great pressure, quickly hardens itself,
so that the combination of a very hard surface with a ductile
back develops spontaneously. As fast as this hard surface
wears away it is replaced by a new one made equally hard by
the deformation which it at once receives.

This hardening probably represents in part the same
cause which leads to the increase of cohesion in general, including
the hardness, of all the malleable metals under all forms of
deformation, such as wire drawing, and in part the marten-
sitizatioiiof the austenite. That is to say, the arrested trans-
formation from austenite through martensite to the alpha state
which is due in cooling through the transformation range but
is restrained by the retarding action of the manganese, is now
stimulated by the deformation sufficiently to .cause it to pro-
ceed as far as the martensitic state, with consequent hardening
and enibrittling effect. This martensitization through the
stimulation of the arrested transformation by deformation is a
common property of austenitic steels which have only a moderate
excess of the retarding elements over the quantity needed for

1 Hadfidd and Hopkinson, Transactunu, Am. Inst. Min. Bii«re., Vol. 50. p. 486 (1914),
and Journal, Iron and Steel Institute, Vol. 89. 1, pp. 112 and 124 (1914).

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8 Topical Discussion on Alloy St^ls.

causing the retention of the austenitic state. It occurs strikingly
in austenitic 20-per-cent nickel steel.^

Turning now to carbon steel, the retarding eflFect of man-
ganese on the structural changes shows itself by leading in
general to finer structure,* to finer ferrite masses, finer network
structiure, and finer pearlite, indeed probably often to the replac-
ing of lamellar pearlite with sorbite. This greater fineness leads
to better quality in general, and to a higher elastic limit in
particular, though of course with a corresponding sacrifice of
ductility. The great value of manganese for this purpose has
not begim to receive the attention which it deserves. It is
probable that a manganese content of say 1.25 per cent, with a
correspondingly lessened ciarbon content, may be used so as to
lessen the danger of cracking and the residual stresses when
a high elastic limit is sought, because this large manganese
content in and by itself raises the elastic Umit by giving a fine-
ness of structiure which otherwise would be sought by increased
violence of cooling or by the use of a lower drawing temperature.
In other words, the use of 1 .25 per cent of manganese lessens the
needed violence of cooling, and permits the use of a higher
residual drawing temperature, in both ways tending to mitigate the
stresses, and in the former way lessening the chances of cracking.

An additional way in which manganese retards and lessens
the rapidity of cooling needed to cause hardening is its retarding
the transformation itself.

The lessening of the rapidity of cooling to which I have
referred may be brought about in various ways, for instance by
substituting oil for water quenching, or air cooling for oil quench-
ing, or quenching in water covered with a film of oil, or with-
drawing the quenched object from the quenching bath after a
predetermined time.

What I have said is wholly consistent with the tendency of
manganese to increase the danger of cracking for given rapidity
of cooling and for given carbon content. It is by enabling us to
lessen the carbon content, or the rapidity of cooling, or both,
that manganese may be made to lessen the danger of cracking.

iCarpeiit«r, Hadfield. and Longmuir, Seventh Report, AOoys Reaearch Conunittae,
(Britiah) Inst. Mech. Bng., 1905. p. 949.

t Henry M. Howe, "Life History of Network and Ferrite Grains in Carbon Sted.*'
Proceedings, Am. Soc. Test. Mats., Vol. XI, pp. 322 and 365 (1911). Howe and Levy, Pro-
uedings, Cleveland Inst. Engineers, July 1914, p. 237.

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THE ROLE of nickel.
By R. R. Abbott.

In its most simple and fundamental form steel is a more or
less rigid mechanic^ mixture of pearlite and iron, the pearlite
itself being a much finer mechanical mixtiire of cementite (FesC)
and iron. In common with such mechanical mixtures the physi-
cal properties of this alloy bear some ratio to the percentage of its
constituents. For various reasons the ratios of these physical
properties are not straight-line functions of the carbon contents.
One of these reasons is that fact that, practically, we do not have
a perfect mechanical mixture, but the iron always carries some
carbide in solution, the amount of which increases with the carbon
content of the alloy. Another reason is the changing ratio
between the areas of the botmdaries between the iron and the
cementite, and the amotmt of these two constituents as the
carbon content varies.

Fig. 1 represents relations existing between the carbon con-
tent and the elastic limit, tensile strength, reduction of area and
precentage of elongation of piure iron-carbon alloys up to 0.9
per cent of carbon (approximately from to 100 per cent of
pearlite). Fig. 1 does not represent ordinary steels, as the influ-
ence of nothing but carbon is considered. For the sake of sim-
plicity and because it represents very accurately true conditions,
it has been drawn as two lines with the break at 0.45 per cent of
carbon. It also represents perfectly annealed alloys. Cementite
is extremely hard, strong and brittle: iron is soft and ductile:
therefore we should expect to obtain with any single alloy, physi-
cal properties depending upon the percentage composition of
the constituents.

Now it is very evident that in order to make a change in the
physical properties of any individual alloy of this series, we could
proceed in one of three ways: (l) To change the nature of the
pearUte; (2) to change the nature of the iron; and (3) to change
the natiure of both the pearlite and the iron. The second cannot
be entirely distinct from the first procedure, because of the iron
in the pearlite.


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Topical Discussion on Alloy Steels.

In practice the physical properties of this simple iron-pearlite
alloy is changed by three methods:

1. Addition of various elements to it;

2. Changing the relative amount of free iron present; and

3. A combination of both methods Nos. 1 and 2.

Under method No. 1, if more than the normal amount of any
element present in a simple carbon steel is added, the steel is




c c 60000


t E 40000

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^ —





"p/ —


c /n.

— i —









c o

0.10 0.20 0.30

0.A0 I 0.50

0.60 0.70 0.80 0.90

Carbon, percent.
Fig. 1. — Physical Properties of Pure Carbon- Iron Alloys,

known as an alloy steel. Under method No. 2 come the various
processes of heat treatment.

When nickel is added to our iron-pearlite alloy it dissolves
entirely in the iron, and the physical properties of the alloy are
changed approximately to the extent we should expect, when we
consider that it is a solid solution of nickel and iron for one ele-
ment and a pearhte with this solution for one of its constituents,
for the other.

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Abbott on the RAle of Nickel. 11

The effect of alloying nickel with pure iron is to increase the
elastic limit, tensile strength, and reduction of area, but to
decrease the percentage of elongation. This effect is the same
when carbon is present, and it is found that a given amount of
nickel produces about the same change in physical properties,
irrespective of the percentage of carbon.

The average effect of nickel up to 8 per cent, upon an iron-
carbon alloy is as follows :

0.01 per cent of nickel increases elastic limit 40 lb. per sq. in.

0.01 " " " " tensile strength. 42

0.01 " " " ". reduction of area . 005 per cent.

0.01 " " " decreases elongation 0.010 " "

Expressing this for a 3.5-per-cent nickel steel, which is the
most common commercial alloy, we see that such a nickel steel
should have 14,000 lb. per sq. in. higher elastic limit, 14,700
lb. per sq. in. higher tensile strength, 1.5 per cent greater reduc-
tion of area, 3.5 per cent less percentage of elongation than a
steel of the same analysis, but without the nickel. (By the per-
centage of reduction of area and elongation, is meant the actual
nmnber of units of change. For example: A steel with no nickel
has a reduction of area of 53 per cent and an elongation of 26
per cent; the same steel with 3.5 per cent nickel woidd have a
reduction of area of 54.5 per cent and an elongation of 22.5
per cent.)

The elastic limit and tensile strength are then increased by
nickel due to the increased properties of the solid solution of the
nickel in the iron. The reduction is practically altered but little,
but the elongation is quite appreciably decreased.

When a plain carbon-iron alloy is heated above the upper
critical point (Ac3), the cementite is dissolved in the iron of the
pearlite at the passage through the lower critical point (Acl) and
this solution progressively dissolves the remaining iron during
the heating up to the Ac3 point, at which point it is all dissolved
and the solution is homogeneous. Upon cooling, the reverse action
takes place, but when nickel is present this separation of the
cementite from the iron-nickel solution does not progress as com-
pletely nor as easily as from a plain iron solution, and therefore
the pearlite areas in a nickel steel are larger and much poorer


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Topical Discussion on Alloy Steels.

defined than would be the case in the same steel without nickel.
This effect becomes more marked the more rapid the cooling,
and since the pearlite areas are much stronger than the iron
areas we find that in practice a nickel steel, compared to one
without nickel, when air cooled, will have a higher increase in
tensile strength than that given above, which represents pre-
fectly annealed alloy.

When steel is broken down too rapidly in rolling, it frequently
shows a decided segregation of the pearlite areas along Unes par-

0.10 a2o



OAO "*^ 030

0.4O aSO^^'* 0.60
Carbon, percent.

Pig. 2. — Critical Temperatures for a Pure Iron-Pearlite Hypo-Butectoid


allel to the rolling direction. Nickel apparently tends to intensify
this effect and occasionally imder even normal rolling this con-
dition is encountered in nickel steel.

Fig. 2 represents the critical temperatures for a pure iron-
pearlite hypo-eutectoid alloy upon heating. Line GOS repre-
sents the upper absorption point (Ac3), MO the magnetic point
(Ac2), and PS the lower absorption point (Acl).

The lower and upper absorption (critical) points upon heat-
ing, as well as the magnetic critical point, are all lowered by the

Digitized by


Abbott on the RdiE of Nickel. 13

addition of nickel. The amount of tlie lowering is given approxi-
mately by the following:

0.01 per cent of nickel lowers GO 0^.235 CX

0.01 " " " " OS 0M80C.

0.01 " " " " MO about 0^.087 C-

0.01 " " " " PS 0«.103C.

In working with the Ac2 point these figures are not based
upon as accurate an investigation as for the Acl and Ac3 points.
As the nickel contents are increased and the critical temperature
progressively lowered, it is evident that finally the upper absorp-
tion point will reach the temperature of the atmosphere (20^ C.)
and we will have an austenitic alloy; the greater the amount of
carbon the less nickel it takes to reach this«condition. Also as
the nickel, increases points O and S (Fig. 2), move to the left
until they finally successively coincide with G. As soon as the
line MO or any point on OS are brought below the temperature
of the atmosphere, we have a non-magnetic alloy.

When a piece of steel is quenched from above the upper
absorption point rapidly enough the result will be the complete

Online LibraryDenton Jaques SniderThe psychology of Froebel's play-gifts → online text (page 1 of 47)