Note: Descriptions are shown in the official language in which they were submitted.
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TITLE
Austenitic Stainless Steel
Including Columbium
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates generally to stainless steel alloys and more
particularly to
the T201 LN stainless steel alloy, and still more particularly to
strengthening the T201 LN
alloy through the addition of columbium (Cb).
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Description of the Prior Art
Materials which are used at sub-zero temperatures should have good ductility,
toughness and strength, which are all properties that are achievable with most
of the
austenitic stainless steels. The T201LN alloy was specifically designed for
such applications
and is unique in that it is designated as an acceptable material for
applications in which high
yield and ultimate strengths are specified. The T201LN alloy, which is
disclosed in United
States Patent No. 4,568,387 to Ziemianski, is an austenitic stainless steel
having good low
temperature properties of austenitic stability, elongation and strength. As
described in the
'387 patent, the compositionally-balanced T201LN alloy consists essentially
of, in weight
percent, 0.03% carbon max., 6.4 to 7.5% manganese, up to 1.0% silicon, 16 to
17.5%
chromium, 4.0 to 5.0% nickel, up to 1.0% copper, 0.13 to 0.20% nitrogen, and
the balance
iron. The T201LN alloy is characterized by austenitic stability, high room
temperature
strength, minimized sensitization to welding, and high strength and ductility
at low
temperatures.
Although the T201LN alloy has been successfully used in sub-zero applications,
the
strength requirements cannot always be achieved in all gages to satisfy the
specifications of
some cryogenic applications. Therefore, it would be desirable to develop
methods to reliably
increase the strength of the T201 LN alloy so that it may more reliably exceed
the mechanical
requirements of material specified for cryogenic applications. Recent interest
has also
surfaced in increasing the strength of the T201LN alloy to expand its use in
structural
applications where it may possible be used to replace carbon steel in the
production of truck
frames and other applications.
Industry attempts to produce high strength 201 series stainless steel have
until now
involved simply evaluating the alloy to determine how much, if any, of the
alloy meets the
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strength requirements. Modifying the amount of nitrogen during melt has also
been
attempted. In any event, alloys are milled and the strength characteristics
are tested. Alloys
which do not meet the strength requirement would be scrapped. Extremely high
scrap rates
were anticipated based on prior production, to a lower 38,000 psi yield
strength. Therefore, a
more reliable means of producing higher strength 201 series stainless steel is
needed.
SUMMARY OF THE INVENTION
The present invention relates to methods for reliably producing high strength
201
series stainless steel. As defined in The Making, Shaping. and Treating of
Steel (10' ed.,
AISI, 1985), p. 1334, an AISI 201 series stainless steel includes: 0.15%
carbon max.; 5.5-
7.5% manganese max.; 1.00% silicon max.; 0.060% phosphorus max.; 0.030% sulfur
max.;
16.00-18.00% chromium; 3.50-5.0% nickel; and 0.25% nitrogen max. The method of
the
present invention focuses on the influence of Cb on the mechanical properties
of the T20ILN
alloy. Laboratory heats of T201 LN alloy, which were significantly alloyed
with nitrogen
(-0.15%) to stabilize the austenite, were made with varying amounts of Cb (as
low as
possible up to approximately 0.20%) to determine the influence the Cb would
have on the
mechanical properties of the alloy. It was found that a significant increase
of at least 5 k.s.i.
is obtained in both the yield and ultimate strengths as the Cb level is
increased above 0.0%5%,
and approximately 10 k.s.i. at Cb levels above 0.150%. The percent elongation
is decreased
from about 55% to 48%, measured hardness is increased from about 89 Rb to
about 98 Rb,
and grain size is decreased from about ASTM 6.5 to about ASTM 10 as Cb content
is
increased from about 0.003% to about 0.210%.
-3-
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Testing has shown that above a residual level of Cb (0.003%), impact energy
increases as Cb content increases to about .10% at the three temperatures
tested. Impact
energy decreases at above about .10% Cb. Ductility remains relatively high at -
50 F and
70 F. A decrease, but not a complete loss, of ductility occurs at a very low
test temperature
of -320 F.
-3A-
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Accordingly, an object of the present invention is to reliably increase the
strength of the T201 LN alloy so that it may exceed the mechanical
requirements of
material specified for cryogenic applications. In this regard, a .06% to .10%
addition
of Cb to a slightly modified version of studied T201LN alloy has been shown to
improve the mechanical characteristics of the alloy for applications in
temperature
down to -320 F.
It is a further object of the present invention to reliably increase the
strength of
the T201 LN alloy for temperatures above -50 F. In this regard, a .10% to .20%
addition of Cb has been shown to improve the mechanical characteristics of the
alloy
for application in temperatures above -50 F.
In light of the foregoing, the present invention is directed to an austenitic
stainless steel of the 201 series that includes, in weight percent, greater
than 0.003%
Cb. The present invention also is directed to a method for providing a high
strength
201 series stainless steel where in the method includes preparing a heat of a
201 series
stainless steel and maintaining the Cb in the heat at a level, in weight
percent, greater
than 0.003%.
In a more preferred aspect, columbium is present in an amount selected greater
than 0.003% up to 0.25% by weight, and preferably greater than 0.03% up to
0.21%
by weight.
In another aspect, the present invention provides a stainless steel which
consists essentially of, in weight percent 0.02% to 0.027% carbon, 6.4 to 7.5%
manganese, up to 1.0% silicon, 16.78 to 17.74% chromium, 4.0 to less than 5.0%
nickel, copper in an amount up to 0.43%, 0.13 to 0.17% nitrogen, greater than
0.075
up to 0.20% columbium, inevitable impurities, and a balance iron.
Other objects and advantages of the invention will become apparent from the
following description of certain presently preferred embodiments thereof.
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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows ferrite maps made on 1/2" thick slices, taken from the bottom of
the laboratory produced ingots, which were then polished and etched before
measurements (FN) were obtained with the Magne-Gage TM;
FIG. 2 is a schematic illustration of the tensile and subsize Charpy specimens
which were used to obtain the mechanical data for this study (with all
dimensions in
inches);
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FIG. 3 is a plot of the yield strength (0.2% offset), obtained from tensile
specimens of
the laboratory melted material of T201 LN alloy, as a function of Cb;
FIG. 4 is a plot of the ultimate strength, obtained from tensile specimens of
the
laboratory melted material of T201 LN alloy, as a function of Cb;
5 FIG. 5 is a plot of the ferrite content, as measured with the Magne-Gage, of
the as-
tested laboratory material, on the tensile blanks;
FIG. 6 is a plot of the magnetic response as measured with the Magne-Gage on
the
tensile samples after mechanical testing;
FIG. 7 is a plot of the % elongation, obtained from tensile specimens of the
laboratory
melted material of T201LN alloy, as a function of Cb;
FIG. 8 is a plot of the hardness, obtained from tensile specimens of the
laboratory
melted material of T20I LN alloy, as a function of Cb;
FIG. 9 is a plot of the grain size as a function of Cb obtained by
metallographic
examination of micros taken from laboratory melted material of T20ILN alloy;
FIG. 10 is a plot of the impact energies as a function of Cb content for the
testing of
subsize Charpy samples (0.180" except the data which are circled) at -320, -50
and 70 F;
FIG. 11 is a plot of the percent shear as a function of Cb content for the
testing of
subsize Charpy samples (0.180" thick) at -320, -50 and 70 F; and
FIG. 12 is a plot of the lateral expansion as a function of Cb content for the
testing of
subsize Charpy samples (0.180" thick) at -320, -50 and 70 F.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Initial testing was conducted which involved making Cb additions to T201 LN
material to provide four heats comprising the following additions of carbon,
nitrogen, and Cb.
Heat # C N C+N Cb Avg. Avg. Grain Plates with #6
Yield Tensile Sizes Grain Size
Yield - Tensile
2C 152 .018 .176 .194 .011 48,000 96,100 6 48,000 96,200
2C153 .014 .175 .199 .013 48,950 95,600 5-6 50,450 96,850
2C077 .022 .170 .192 .030 48,333 96,533 5-7 49,700 97,300
2C078 .025 .180 .205 .050 52.550 101,867 6-8 53,450 103,800
The initial testing involved providing eleven groups of plates from the four
heats as
follows:
Heat I.D. No. Gage R.T. R.T. Elong. G.S. Ft/Lbs. - Size Lateral
No. Yield Tensile 320F Expan. -
320F
2C077 21301 .370 46,700 95,400 59.7 5 55.5/52/59.5 3/4 30/30/30
91114 .437 49,700 97,300 59.1 6 44.5/47/55.5 3/4 37/44/38.5
24006 .437 48,600 96,900 61.8 7 68/53/64 3/4 44/36/43
2C078 21303 .370 52,000 101,000 57.5 8 42/43/42 3/4 33/36.5/32
21302 .437 53,450 103,800 58.3 6 60/60/60 Full 28/26/31
24005 .437 52,200 100,800 61 7 66/50/63 3/4 40/31/41
2C152 24007 .370 48,000 96,200 60.3 6 60/66/51 3/4 41/45/33
2C 153 24008 .370 49,100 96,800 59.2 6 63/59/63 3/4 43/39.5/43
24009 .370 48,300 95,000 61.2 5 67/67/79 3/4 42/44/50
91242 .370 51,800 96,900 P5695 6 75/76/72 3/4 35/37/33/5
24010 .370 46,600 93,700 5 54/55/50 3/4 35.5/37/34.5
Original
24010 .370 47,500 93,800 5
Retest
240102% .370 57,300 96,700 55/40.5/49.5 3/4 37/26/35/5
Stretch
All plates from all four heats showed excellent impact and lateral expansion
values at
320 F. The standard composition had been marginal at times and was of concern
to the
intended cryogenic tank fabricators. The pressure vessel code requires a
minimum of 15 mils
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lateral expansion after welding. The average lateral expansion values of 201
LN prior to this
trial were 31 mils. The average of the high Cb heat was 35 and the other heats
averaged 39.
This is the expected improvement due to the more austenitic compositions of
this trial.
The three heats of .17% to .18% nitrogen without Cb did not have sufficiently
high
enough yield or tensile strength after processing from ingots. Several groups
were marginal
and one plate failed with a 93,700 psi tensile versus 95,000 psi minimum.
(Slip # 24010,
Heat 2C153, yield strength was 46,600 psi).
The fourth heat (Heat 2C078) as shown has acceptable strength, which appears
to
result from the .05% Cb addition, as is discussed later. Finer grain size also
results from the
high Cb content. All plates with #6 grain size were shown by heat to separate
that variable
from the comparison.
During rolling, all plates had work below 1600 F. The first two heats had
more
reduction below 1500 F via a 1500 F hold in the reheat furnace at 150% of
the final gage
except for one plate of 21302. This plate was direct rolled without reheat
like the second two
heats (2C152 and 2C153). This plate still had work below 1500 F and compares
favorably
with the reheated plates.
Heat 2C078 shows considerably higher yield and tensile strength than the other
heats
without as much Cb. Impact and lateral expansion values at -320 were also
very good.
There is no restriction in the applicable specifications against the addition
of Cb or other
elements. The lower Cb (.03%) heat 2C077 does show that level of Cb to be
insufficient.
Earlier 201LN sheet experience over .17% nitrogen found blistering and
porosity to
be a problem. None of the plates from the above heats showed any blistering or
porosity.
Product checks found up to .198% nitrogen. If only nitrogen was used for
strength, it would
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appear that more than .20 % nitrogen would be needed, but this has not been
tried recently.
There is reluctance to continuous cast over .16% nitrogen.
The initial rolling of 2200 F oxidizing atmosphere was changed to 2150 F
reducing
atmosphere after seeing a rough surface due to heavy scale. No evidence of
intergranular
attack was seen after dip pickling. It was thought that the hot rolling
roughness may have had
a deleterious effect on the test properties. Room temperature tensile samples
were polished
without improving the properties. However, for the -320 F tensile test,
improvement was
seen in the elongations when a subsize round was used versus the flat sample
which had
several cracks starting at the hot rolled surface roughness.
There is no minimum tensile properties at -320 F currently, but earlier data
show low
elongations in certain 201L plates at -320 F.
Shown below are the -320 F and corresponding room temperature (R.T.) results:
Heat # I.D.# Sample Sample Test Yield PSI Tensile PSI Elong. %
Size Type Temp. ( F)
2C078 21302 .464"x 2" Flat -320 100,400 134,400 4.5
21302 Flat -320 115,900 134,500 5.0
21302 .250x 1.0 Round -320 106,100 218,400 25.0
21303 .350x1.4 Round -320 103,055 186,542 20.0
21303 .350x 1.4 Round -320 102,649 192.701 19.3
2C077 91114 .350x 1.4 Round -320 90,314 196,397 21.4
91114 .350x 1.4 Round -320 104,772 176,382 20.0
2C078 21302 .437x2.0 Flat R.T. 53,450 103,800 58.3
21303 .370x2.0 Flat R.T. 52,000 101,000 57.7
2C077 91114 .437x2.0 Flat R.T. 49,700 97,300 59.1
Previous 201LN product was annealed at 2025 F with later plates using 1950
F. An
anneal study done on hot rolled samples from heat 2C078 showed 1950 F to be
the best
choice. All plates in this study were annealed at 1950 F.
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Due to concerns about diminishing the impact properties, none of the plates
were
stretcher leveled initially.
After plate 24010 failed the tensile strength, it was given a 2% stretch to
evaluate the
effects. The results shown after the first two roller levelled results show a
large yield and
notable tensile increase. The impact properties were still acceptable after
stretching. It is
clear that they were not greatly diminished, if at all. Impact testing
recognizes that a test may
be low due to testing variance. This one sample with 40.5 ft. lbs. and 26 mils
lateral
expansion is still above acceptable values.
These increases in strength from stretching can be expected to be lost in the
welded
joints of the tank and do not contribute to the true strengthening of the
product as does a
compositional change. Special weld procedures currently used by the largest
201 LN
potential customer are adding to the total fabrication cost due to the need to
preserve the
marginal tensile properties of the standard 201 LN plate. These improvements
in the
composition for higher tensile strength would be of value.
As is described in greater detail below, additional testing was performed.
Three
laboratory heats of T201 LN were melted with various additions of Cb in the
range of 0.003-
0.210%. The material was hot rolled to -.3/16" (4.76 mm) and annealed at 1950
F. Tensile
and subsize Charpy specimens were obtained from each of the plates for
mechanical testing.
Measurements were made on the tensile specimens before and after testing to
determine the
ferrite content of the plate and the stability of the austenite. Micros were
also obtained from
the ends of the tensile specimens which were then polished and etched so that
the grain size
could be measured.
A significant increase of at least 5 k.s.i. is obtained in both the yield and
ultimate
strengths as the Cb level is increased above 0.075%, and approximately 10
k.s.i at Cb levels
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above 0. 150%. The percent elongation is decreased from about 55% to 48%,
measured
hardness is increased from about 89 Rb to 98 Rb, and grain size is decreased
from about
ASTM 6.5 to ASTM 10 as Cb content is increased from 0.003% to 0.2 10%. Above a
residual
level of Cb (0.003%), impact energy is increased slightly as Cb content
increased at the three
5 temperatures tested up to .10% Cb. Ductility remains relatively high at -50
and 70 F. A
decrease, but not complete loss, of ductility occurs at a very low test
temperature of -320 F
above.10% Cb. The addition of Cb enhances the mechanical properties of the
T201 LN alloy.
Based on the data obtained on laboratory melted and processed material, an
addition
of approximately .075% Cb is sufficient to enhance the strength mechanical
properties of this
10 alloy without significantly degrading any of the other mechanical
properties.
The specific procedure and results of the additional testing were as follows.
Three
fifty pound VIM laboratory heats were melted to the general chemistry aims of
the T201 LN
alloy which is commercially produced. Table 1 contains the chemistries of the
three
laboratory heats that were melted for this study along with the minimum,
average and
maximum of the three commercial heats of T201 LN which were previously melted.
The first
heat. RV # 1184, was melted to examine the influence of Cb additions in the
range 0.01-
0.10% by weight on the mechanical properties of T201 LN. However, the final
chemistry of
this first heat was slightly off the commercial chemistry of T201 LN.
Therefore a second heat,
RV #1185, was melted. Later in the investigation, it was decided to examine
the influence of
slightly higher Cb contents (up to 0.20%) on the mechanical properties of this
alloy, so a third
and final heat, RV #1212, was melted. Once each heat was melted, it was cast
into three
seventeen pound ingots with the Cb content adjusted to various levels in
between the pouring
of the three individual ingots/heat. The purpose of this was to have
essentially three identical
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alloys from which the influence of the varying Cb content on the mechanical
properties of the
alloy could be studied.
A half-inch slice was cut from the bottom of each ingot which was then
polished and
etched so that ferrite maps could be obtained on the as-cast material. The
Ferrite Number
(FN) measurements were obtained along a half-inch by half-inch grid on each of
the 2-3/8"
square ingot slices with the Magne-Gage to ascertain the stability, with
respect to austenite, of
these alloys. These ferrite maps are shown in Figure 1 for heats RV #184, RV
#1185 and RV
#1212 respectively. The ingots were ground and heated to 2150 F (-1 hr TAT)
for hot
working. They were cross rolled to obtain a width of seven inches and then hot
rolled to an
aim gage of - 0.1875". Each panel was then annealed at 1950 F for six minutes
(TAT)
followed by grit blasting and pickling. Tensile specimens were cut and
machined from each
of the plate samples in both the longitudinal and transverse directions.
Charpy v-notch
impact specimens were also cut and machined from each of the plate samples
from the
transverse direction. A schematic of the tensile and subsize Charpy specimens
(0.394" x
thickness of the plate material) used in this study are shown in Figure 2.
Samples were cut from the ends of the tensile specimens for microstructure
evaluation
after the mechanical tests were completed. These were mounted, polished and
electrolytically
etched in 10% oxalic acid at 6V for 20 - 30 seconds to reveal the general
grain structure. The
grain size of each sample was estimated per ASTM E 112 using the comparison
procedure
with the following two exceptions. The first is that the photomicrographs were
taken at a
magnification of 106X instead of 100X. The second is that the photomicrographs
were
compared to standards from Plate I and not Plate II, which is the recommended
standard for
austenitic stainless steels. Therefore, the grain sizes measured in this
report should be used
only to characterize and compare the material which is described within this
report.
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However, it should be noted that these minor variations in the grain size
measuring technique
should not significantly alter the grain size and/or the trend (grain size as
a function of Cb
content).
Table 2 contains the results which were obtained on or from the testing of the
tensile
specimens. Table 3 contains the results obtained from testing of the Charpy
specimens. The
results obtained from duplicate test specimens were averaged to simplify the
graphical
representation of the data. Where both longitudinal and transverse specimens
were tested, an
average of all the samples is also given. An example of this is the data which
are plotted in
Figures 3 and 4 of the yield (0.2% offset) and ultimate strengths,
respectively, as a function of
Cb content. As can be seen, both plots show an increase in the strength of
T201LN as the Cb
content is increased from -0.003 to 0.210%. A significant increase of at least
5 k.s.i. is seen
in both the yield and ultimate strengths as the Cb level is increased above
0.075%. The
increase is approximately 10 k.s.i. at Cb levels above 0.150%. In Figure 3,
there is an
abnormally high yield strength associated with a low Cb level material (RV
#1184 - Ingot A)
which does not conform to the trend shown by the rest of the data. However, it
should be
noted that this material had the highest ferrite level (-2.5%) as measured on
the tensile
blanks, before testing.
Figure 5 is a plot of the ferrite content measured on the tensile blanks
before testing.
Only three of the materials examined in this study had a significant amount of
ferrite. The
first two of these are from the laboratory heat RV #1 1 84 (ingots A & B)
which did not match
the commercially produced chemistry. The higher ferrite levels observed in
this heat are due
to the higher chromium and molybdenum and lower nickel and manganese contents.
The
cause of the higher-than-expected ferrite level in the material from ingot C
of laboratory heat
RV #1185 is unknown but may be due to fluctuations in the heat treating
process which
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reduces the ferrite level from that which is found in the as-cast material
(shown in Figure 1)
to that in the final product.
The magnetic response (FN) was also measured along the shaft of the tensile
specimens after testing to determine the presence of martensite which is a
measure of the
austenite stability. These data are shown in Figure 6 for future reference.
This measurement
is an indication of the amount of martensite in the material. However, the
relationship
between this measurement and actual amount of martensite is not known and
therefore should
only be used for comparison between these samples.
The elongation and hardness measurements obtained from the tensile testing and
the
grain size obtained from the metallographic examination of micros cut from the
tensile
specimens (from the ends which were not deformed during testing) are shown in
Figures 7, 8
and 9, respectively. The percent elongation decreases (Figure 7) and the
measured hardness
(Figure 8) of the material increases as the Cb content of the material
increases.
The data that were obtained from impact testing of the subsize Charpy
specimens (i.e.
< 0.394" thick) included the impact energies (Figure 10), percent shear
(Figure 11) and the
lateral expansion of the samples (Figure 12) as a function of Cb for three
different
temperatures (320 F, -50 F and 70 F). It should be noted that the data points
in Figure 10
which are circled were obtained from the material of Heat RV # 1212, ingot A,
which was
accidentally rolled to a lighter gage (0.157") than that of the rest of the
material which was
rolled to a gage of 0.180 - 0.185". Due to the fact that the impact energy is
dependent upon
the cross-section of the sample being tested, these samples (from Heat
RV#1212) would have
had at least 18% higher impact energy if they were the correct thickness
(0.180 - 0.185").
Therefore, these data were not considered when examining the impact energy, %
shear and
lateral expansion trends as a function of Cb content.
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The impact energies initially increase and then decrease as the Cb content
increases.
Very little, if any, loss of toughness was observed between the testing at 70
and -50 F.
However, the tests that were completed at -320 F showed a decrease in the
toughness of the
material above .10% Cb. However, it should be noted that the impact properties
at this
temperature still show a respectable level of toughness.
The Cb addition up to .10% was successful in increasing the strength of this
alloy
without significantly degrading any of the other mechanical properties tested.
Examination
of the data suggests that about .075% Cb is an appropriate addition to achieve
the desired
mechanical properties.
Due to the fact that Cb is a strong stabilizer (i.e., retards the formation
chromium
carbides at grain boundaries), the addition of Cb to this alloy may allow the
maximum carbon
content to be relaxed and still be acceptable from a corrosion standpoint.
This addition of Cb
along with a slight increase in the carbon content may insure the enhanced
mechanical
properties needed for these new markets (additional strength and toughness due
to the
increased austenite stability). Therefore, a variation of the T201 grade (Cb
0.100% & C
0.060% max.) may produce an acceptable product in the as-welded condition.
Based upon the results obtained on laboratory produced material, the addition
of Cb
acts as a grain refiner and enhances the mechanical properties of the T201 LN
alloy. It was
concluded that a significant increase of at least 5 k.s.i. is obtained in both
the yield and
ultimate strengths as the Cb level is increased above about 0.075%, and an
approximately 10
k.s.i. increase is obtained at Cb levels above 0.150%. Further, the percent
elongation is
decreased from about 55% to 48%, measured hardness is increased from about 89
Rb to 98
Rb and grain size is decreased from ASTM 6.5 to ASTM 10 as Cb content is
increased from
0.003% to 0.210%. In addition, above the residual level of Cb (-Ø003%), the
impact energy
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is increased as Cb content is increased up to about .10% at the three
temperatures tested.
Ductility remains relatively high at -50 and 70 F. At above about .10% Cb. a
decrease, but
still acceptable ductility occurs at the low test temperature of -320 F.
While certain presently prefered embodiments have been shown and described, it
is
distinctly understood that the invention is not limited thereto but may be
otherwise embodied
within the scope of the following claims.
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16
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SUBSTITUTE SHEET (RULE 26)
CA 02316332 2000-06-22
WO 99/32682 PCT/US98/27602
17
Table 2
Sample Cb Initial Dimensions Sample Hard- Initial Ferrite Final Femte
I.D. # (Wt %) Gage Width Orienta- ness Reading Reading
Lion (Rb) FN(1) FN(2) FN(1) FN(2)
1184A 0.003 0.180 0.501 L 86.5 2.3 2.3 18.2 18.5
0.179 0.501 11 2.3 2.3 20.5 19.5
0.176 0.501 T 90.4 1.5 3.9 19.8 16.4
0.172 0.502 " 1.8 3.9 19.5 17.5
1184B 0.029 0.186 0.501 L 90.3 1.5 1.3 13.6 15.7
0.186 0.500 1.0 1.8 11.3 12.3
0.188 0.501 T 92.5 1.8 2.6 17.5 16.7
0.189 0.501 2.8 1.5 18.2 15.1
1184C 0.100 0.183 0.499 L 90.5 0.0 0.0 9.8 7.4
0.183 0.498 0.0 0.0 8.7 7.4
0.188 0.500 T 95.3 0.0 0.0 8.7 8.5
0.187 0.500 11 0.0 0.0 8.5 8.5
1185A 0.003 0.186 0.498 L 95.3 0.0 0.0 11.0 10.5
0.185 0.499 " 0.0 0.0 15.1 13.4
0.183 0.499 T 90.0 0.5 0.0 11.6 12.6
0.181 0499 0.0 0.3 14.1 13.1
1185B 0.046 0.186 0.501 L 88.0 0.0 0.0 10.8 9.5
0.187 0.501 0.0 0.0 10.0 8.5
0.181 0.501 T 94.0 0.0 0.0 11.3 11.3
0.182 0.501 11 0.0 0.0 11.0 10.5
1185C 0.120 0.185 0.498 L 94.2 1.3 1.3 14.1 11.3
0.186 0.498 1.3 1.3 15.4 11.6
0.186 0.498 T 96.3 0.8 0.8 15.1 15.4
0.187 0.497 1.0 1.0 13.4 15.4
1212A 0.078 0.156 0.499 L 94.3 0.0 0.0 12.8 10.5
0.157 0.500 0.0 0.2 13.9 12.3
0.158 0.499 T 0.0 0.0 10.8 11.3
0.158 0.500 0.0 0.0 12.6 11.5
1212B 0.160 0.180 0.499 L 97.6 0.0 0.0 10.8 10.3
0.181 0.499 0.0 0.0 13.6 11.5
0.186 0.499 T 0.0 0.0 12.1 13.3
0.186 0.499 0.0 0.0 12.3 13.1
1212C 0.210 0.181 0.500 L 97.8 0.0 0.2 16.9 17.2
0.178 0.499 0.0 0.0 12.3 14.6
0.180 0.500 T 0.0 0.0 12.8 10.3
0.181 0.499 0.0 0.0 12.6 13.9
-17-
SUBSTITUTE SHEET (RULE 26)
................ .
CA 02316332 2000-06-22
WO 99/32682 18 PCT/US98/27602
Table 2 (continued)
Sample Uniform Elongat Grain Grain Strain Strength (p.s.i.)
I.D. # Deformed Region ion (%) Size IU Size Hardening Yield Ultimate
Width Gage Anneal Ind Exp. (0.2%)
Anneal n(1) n(2)
1184A 0.421 0.148 55 7.5 0.23 0.43 57100 105200
0.420 0.148 53 0.23 0.43 57500 103900
0.417 0.146 53 7.5 7.0 0.24 0.44 51100 104500
0.423 0.143 54 7.5 0.24 0.44 48500 103800
1184B 0.423 0.155 54 6.5 0.24 0.44 49400 103200
0.423 0.153 54 0.24 0.42 49900 102000
0.420 0.154 54 7.0 6.5 0.24 0.40 48800 103800
0.417 0.155 54 7.0 0.24 0.38 48200 102700
1184C 0.422 0.154 50 10.0 0.23 0.39 58500 108200
0.428 0.153 51 0.24 0.39 56400 108200
0.422 0.158 50 9.5 9.5 0.23 0.39 53600 109400
0.424 0.158 50 9.5 0.23 0.39 55000 109300
1185A 0.415 0.153 57 6.5 0.26 0.45 49100 101300
0.415 0.154 57 0.26 0.46 47900 103000
0.417 0.153 55 6.5 6.0 0.26 0.46 46100 103300
0.415 0.152 55 6.0 0.25 0.46 47500 102800
1185B 0.422 0.151 54 6.5 0.26 0.46 45700 98600
0.418 0.150 54 0.26 0.44 44900 96500
0.418 0152 55 6.0 6.5 0.26 0.45 47800 103900
0.420 0.152 55 6.5 0.26 0.44 48600 103300
1185C 0.423 0.151 51 9.0 0.23 0.38 54700 104500
0.424 0.153 52 0.24 0.39 55100 105700
0.423 0.156 50 8.5 10.0 0.24 0.40 50800 108600
0.420 0.154 52 9.5 0.23 0.40 56100 109200
1212A 0.425 0.133 52 8.5 0.24 0.41 55200 108400
0.420 0.133 52 0.24 0.43 54700 108400
0.417. 0.130 52 8.0 8.5 0.25 0.42 54200 109200
0.418 0.130 51 8.0 0.24 0.41 54400 109600
L 1212B 0.420 0.153 51 10.0 0.23 0.38 57900 110300
0.417 0.148 51 0.23 0.39 58600 112100
0.415 0.153 50 10.0 9.5 0.23 0.39 57900 113400
0.422 0.157 49 10.0 0.23 0.39 58700 113100
1212C 0.420 0.152 50 10.0 0.23 0.41 58500 113400
0.420 0.148 50 0.24 0.38 57300 112600
0.425 0.150 46 10.0 10.0 0.24 0.39 56400 112000
0.421 0.151 47 10.0 0.24 0.39 57100 112400
- 18-
SUBSTITUTE SHEET (RULE 26)
CA 02316332 2000-06-22
WO 99/32682 PCTIUS98/27602
19
Table 3
Sample Cb Testing Annealed @ 1950 F for 6 min. Reannealed @ 1950 F for 6 min.
I.D. # (wt %) Temp (TAT) (TAT)
( F) Impact Lateral Impact Lateral
Energy Expansion Energy Expansion
(ft-lbs) % Shear (in) (ft-lbs) % Shear (in)
1184A 0.003 -320 21.0 10 0.023 28.5 10 0.026
1184A 0.003 -320 18.5 10 0.018 23.0 10 0.034
1184A 0.003 -320 24.0 15 0.021 16.0 5 0.021
1184B 0.029 -320 42.0 20 0.025 27.5 10 0.038
1184B 0.029 -320 22.5 15 0.024 26.0 10 0.037
1184B 0.029 -320 40.0 15 0.033 27.0 10 0.041
1184C 0.100 -320 24.0 10 0.018 13.5 5 0.020
1184C 0.100 -320 20.0 5 0.020 13.0 5 0.013
1184C 0.100 -320 19.0 5 0.021 13.0 5 0.016
1185A 0.003 -320 24.0 10 0.014 26.0 5 0.035
1185A 0.003 -320 30.0 10 0.021 25.0 5 0.041
1185A 0.003 -320 24.0 15 0.016 25.0 5 0.028
1185B 0.046 -320 30.0 10 0.034 32.0 10 0.035
1185B 0.046 -320 28.5 10 0.032 27.0 10 0.024-
1185B 0.046 -320 26.0 10 0.023 24.0 5 0.029
1185C 0.120 -320 17.0 5 0.013 17.5 5 0.019
1185C 0.120 -320 15.0 5 0.018 14.0 5 0.019
1185C 0.120 -320 16.0 5 0.016 14.0 5 0.018
1212A 0.078 -320 14.0 5 0.013 19.0 5 0.020
1212A 0.078 -320 19.0 5 0.011 14.0 5 0.020
1212A 0.078 -320 25.0 5 0.022
1212B 0.160 -320 11.5 5 0.016 13.0 5 0.020
1212B 0.160 -320 15.0 5 0.017 12.0 5 0.019
1212B 0.160 -320 13.0 5 0.015
1212C 0.210 -320 11.5 5 0.011 11.0 5 0.012
1212C 0.210 -320 14.0 5 0.010 11.5 5 0.015
1212C 0.210 -320 11.0 5 0.013
11 84A 0.003 -50 38.0 80 0.044 46.0 60 0.051
1184A 0.003 -50 42.5 75 0.059 44.0 55 0.044
1184A 0.003 -50
1184B 0.029 -50 47.5 85 0.057 45.0 60 0.055
1184B 0.029 -50 51.5 90 0.058 53.0 50 0.054
1184B 0.029 -50
1184C 0.100 -50 38.0 60 0.043 42.0 45 0.048
1184C 0.100 -50 38.5 65 0.032 42.0 55 0.059
1184C 0.100 -50
1185A 0.003 -50 41.0 60 0.040 46.0 35 0.041
1185A 0.003 -50 38.5 65 0.055 46.0 35 0.054
1185A 0.003 -50
1185B 0.046 -50 43.0 65 0.051 50.0 50 0.054
1185B 0.046 -50 44.0 75 0.038 52.0 50 0.049
SUBSTITUTE SHEET (RULE 26)
CA 02316332 2000-06-22
WO 99/32682 20 PCT/US98/27602
Table 3 (continued)
Sample Cb Testing Annealed Lu 1950 F for 6 min. Reannealed @ 1950 F for 6 min.
I. D. (wt %) Temp (TAT) (TAT)
( F) Impact Lateral Impact Lateral
Energy Expansion Energy Expansion
(ft-lbs) % Shear (in) (ft-lbs) Shear (in)
1185B 0.046 -50
1185C 0.120 -50 36.5 70 0.039 39.5 55 0.051
1185C 0.120 -50 39.0 80 0.044 40.0 45 0.043
1212A 0.078 -50 33.5 75 0.025 32.0 60 0.047
1212A 0.078 -50 31.5 70 0.026 33.5 65 0.049
1212A 0.078 -50
1212B 0.160 -50 36.5 70 0.037 36.0 50 0.040
1212B 0.160 -50 34.0 80 0.040 37.0 50 0.047
1212B 0.160 -50
1212C 0.210 -50 34.0 50 0.025 34.0 40 0.044
1212C 0.210 -50 30.5 50 0.025 32.0 40 0.046
1212C 0.210 -50
1184A 0.003 70 42.5 90 0.053 41.0 70 0.052
1184A 0.003 70 42.0 95 0.056 42.0 75
1184A 0.003 70 40.0 60 0.055
1184B 0.029 70 48.0 95 0.064 51.0 85 0.059
1184B 0.029 70 48.5 90 0.058 46.0 75
1184B 0.029 70 50.0 75 0.059
1184C 0.100 70 39.5 80 0.055 42.5 55 0.047
1184C 0.100 70 40.0 85 0.053 44.0 65
1184C 0.100 70 41.5 55 0.044
1185A 0.003 70 41.0 90 0.047 45.0 50 0.058
1185A 0.003 70 41.5 90 0.061 44.5 55
1185A 0.003 70 44.0 50 0.049
1185B 0.046 70 45.5 95 0.051 50.0 60 0.054
1185B 0.046 70 45.0 90 0.056 51.0 60
1185B 0.046 70 49.5 50 0.053
1185C 0.120 70 45.0 95 0.056 42.5 55 0.060
1185C 0.120 70 41.5 85 0.059 45.0 60
1185C 0.120 70 42.0 50 0.051
1212A 0.078 70 29.5 95 0.052 34.0 65 0.047
1212A 0.078 70 28.0 90 0.050 34.0 65
1212A 0.078 70 31.5 65 0.051
1212B 0.160 70 32.0 90 0.044 39.0 50 0.047
1212B 0.160 70 32.0 90 0.046 37.0 50
1212B 0.160 70 36.0 60 0.042
1212C 0.210 70 30.0 80 0.043 34.0 50 0.046
1212C 0.210 70 30.0 85 0.047 34.0 45
1212C 0.210 70 32.0 55 0.036
-20-
SUBSTITUTE SHEET (RULE 26)
