Bohler-Edelstahl GmbH & Co. KGv.Rovalma S.A.

Patent Trial and Appeal Board

Apr 20, 2016

12376866 (P.T.A.B. Apr. 20, 2016)

Trials@uspto.gov Paper 42
571-272-7822 Entered: April 20, 2016

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

BÖHLER-EDELSTAHL GMBH & CO. KG.,
Petitioner,

v.

ROVALMA, S.A.
Patent Owner.
____________

Case IPR2015-00150
Patent 8,557,056 B2
____________

Before MICHAEL P. TIERNEY, RAMA G. ELLURU, and
ROBERT A. POLLOCK Administrative Patent Judges.

POLLOCK, Administrative Patent Judge.

FINAL WRITTEN DECISION
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73

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I. INTRODUCTION
Petitioner, BÖHLER Edelstahl GmbH & Co. KG (“BÖHLER
Edelstahl”), filed a Petition requesting inter partes review of claims 1–4 of
U.S. Patent No. 8,557,056 B2 (“the ’056 patent”). Paper 1 (“Pet.”). Patent
Owner, Rovalma, S.A. (“Rovalma”), filed a Preliminary Response. Paper
12 (“Prelim. Resp.”). We determined that there was a reasonable likelihood
that Petitioner would prevail in challenging those claims as unpatentable.
Pursuant to 35 U.S.C. § 314, therefore, we authorized an inter partes review
to be instituted, on April 22, 2015. Paper 14 (“Dec.”).
After institution, Patent Owner filed a Patent Owner Response (Paper
25, “PO Resp.”), and Petitioner filed a Reply (Paper 30, “Reply”). Patent
Owner also filed objections to Petitioner’s exhibits 1013, 1013 (corrected),
and 1014. Paper 27.
An oral hearing was held on February 12, 2016. A transcript of the
hearing has been entered into the record of the proceeding as Paper 41
(“Tr.”).
We have jurisdiction under 35 U.S.C. § 6(b). This Final Written
Decision is issued pursuant to 35 U.S.C. § 318(a) and 37 C.F.R. § 42.73.
For the reasons that follow, we determine that Petitioner has shown by
a preponderance of the evidence that claims 1–4 of the ’056 patent are
unpatentable.
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A. Related Matters
The ’056 patent is not currently asserted in any parallel proceeding.
Pet. 2; Tr. 64:13–15.
B. The ’056 patent
The ’056 patent involves hot-work steel that has a high thermal
conductivity for use as tool steel. Ex. 1001, Abstract. Hot-work steels are
used for producing hot-work steel objects (e.g., extrusion and die-casting
dies, forging tools, and punches) and, therefore, need to have special
mechanical strength properties at high working temperatures. Ex. 1001,
1:18–25. For example, hot-work tools produced from hot-work steel, along
with having adequate hardness and strength, “must have not only high
mechanical stability at relatively high working temperatures[,] but also good
thermal conductivity and good high-temperature wear resistance.” Id. at
1:31–37.
The Specification of the ’056 patent reveals that tool steels typically
have a thermal conductivity of about 18 to 24 W/mK at room temperature,
and “conductivities of the hot-work steels known from the prior art are
approximately 16 to 37 W/mK.” Id. at 1:48–52. A problem that the ’056
patent sought to solve is the inadequacy of thermal conductivity for various
applications. Id. at 4:11–19. The Specification addresses this problem by
providing: (1) a hot-work steel composition having high thermal
conductivity, as well as; (2) a process by which a specific thermal
conductivity of hot-work steel can be achieved. Id. at 4:23–31; 6:41–44.
With respect to the former, the ’056 patent provides three general
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chemical formulas for hot-work tool steel compositions (id. at 5:1–60) and
five Examples of hot-work steel alloys suitable for particular applications
(id. at 14:20–16:28). In addition to iron and “unavoidable impurities,” “the
tool steel according to the invention contains the elements C (or C and N or
C, N, and B), Cr, Mo and W1 in the ranges [>2% by weight, 0 to 10% by
weight, and 0 to 15% by weight, respectively].” Id. at 5:64–6:1. High
thermal conductivity may be achieved by minimizing chromium and carbon
in the steel matrix. Id. at 6:5–9. “Chromium can only be kept out of the
matrix, by not being present at all. Carbon can be bound in particular with
carbide formers, where Mo and W are the lowest-cost elements and, both as
elements and as carbides, have a comparatively high thermal conductivity.”
Id. at 6:9–13; see also id. at 12:16–20 (“A depletion of chromium together
with the reduction in the carbon content in the matrix leads to an improved
thermal conductivity, in particular if this is brought about by tungsten and/or
molybdenum carbides.”); 6:49–61 (disclosing additional carbide formers);
7:6–13.
Carbides are crystalline particles of carbon bonded to other elements
such as tungsten, chromium, vanadium, and molybdenum and embedded
within the solid solution steel matrix (see, e.g., PO Resp. 2–3; Ex. 1001
6:49–61) as illustrated below in Figure 1 of the ‘056 patent.

1 Chromium, molybdenum, and tungsten, respectively.
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Figure 1 is a schematic of primary carbides 1 and secondary carbides 2
embedded in iron-rich metallic matrix 3. Id. at 7:41–51. The Specification
discloses that the thermal conductivity depends largely on the structure of
carbides within the matrix, wherein the generation of relatively large and
elongated carbides is “particularly advantageous” in increasing the overall
thermal conductivity of the steel. See Ex. 1001 at 6:62–65, 7:36– 8:35; PO
Resp. 9, 22.
In addressing the process by which a specific thermal conductivity of
hot-work steel can be achieved, the Specification teaches the selection of
production conditions to “influence the resultant carbide size,” and, thus
affect the thermal conductivity of the steel. See Ex. 1001, 12:21–38. Table
6 of the Specification, for example, demonstrates that different heat
treatments—in this case, austenitizing temperatures and cooling protocols—
result in different thermal properties.2 Id. at 17:47–55, 21:24–36.

2 We note, however, that the Specification does not indicate how, or
whether, the differences in thermal conductivity shown in Figure 6 relate to
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According to the Specification, the disclosed process for setting thermal
conductivity in hot-work steel to a desired value entails metallurgically
creating an internal structure of the steel “in a defined manner such that the
carbidic constituents thereof have a defined electron and phonon3 density
and/or the crystal structure thereof has a mean free length of the path for the
phonon and electron flow that is determined by specifically created lattice
defects.” Id. at 4:36–47. The resulting internal structure of carbidic
constituents may thus provide:
an increased electron and phonon density and/or which has as a
result of a low defect content in the crystal structure of the
carbides and of the metallic matrix surrounding them an
increased mean free length of the path for the phonon and
electron flow. This measure . . . allows the thermal conductivity
of a steel to be set in a defined manner.
Id. at 4:50–63.
C. Illustrative Claim
Of the challenged claims, claims 1 and 4 are independent. Claim 1,
reproduced below, is illustrative (italics added):

Figure 1 or any aspect of internal structure. See Tr. 101:21–103:7.
3 “Heat is transported through metals and alloys by phonons and free
electrons.” Exhibit 2009, 265 (Bayati and Elliott, Influence of matrix
structure on physical properties of an alloyed ductile cast iron, 15 MAT. SCI.
TECH. 265 (1999)). According to Encyclopaedia Britannica online, a
phonon is a discrete unit of vibrational mechanical energy arising from the
oscillation of atoms within a crystal. “Whereas electrons are responsible for
the electrical properties of materials, phonons determine such things as the
speed of sound within a material and how much heat it takes to change its
temperature.” http://www.britannica.com/EBchecked/topic/457336/phonon
(last visited April 20, 2015).
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1. A process for setting a thermal conductivity of a hot-
worksteel, which comprises the steps of:
providing a hot-work steel, including carbidic constituents
and, by weight, 2–10% Mo+W+V;
metallurgically creating an internal structure of the steel in
a defined manner such that carbidic constituents thereof
have at least one of a defined electron and phonon
density and a crystal structure thereof having a mean free
length of a path for a phonon and electron flow being
determined by specifically created lattice defects;
selecting:
a) a surface fraction and thermal conductivity of the
carbidic constituents and a particular surface fraction
and thermal conductivity of a matrix material
containing the carbidic constituents; or
b) a volume fraction and thermal conductivity of the
carbidic constituents and thermal conductivity of the
matrix material containing the carbidic constituents;
and
setting the thermal conductivity of the steel at room
temperature to more than 42 W/mK.
Ex. 1001, 21:59–22:14. Depending from claim 1, claims 2 and 3 recite
the steps of setting the thermal conductivity of the steel at room
temperature to more than 48 W/mK and 55 W/mK, respectively.
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D. Instituted Grounds of Unpatentability
We instituted the instant trial based on the following grounds of
unpatentability (Dec. 18–19):
Claims Basis References
1–4 § 103(a) EP ’8134 and CH ’8935
1–4 § 103(a) EP ’813 and JP ’2416
1–4 § 103(a) EP ’813 and JP ’6507
1, 2, and 4 § 103(a) EP ’813 and JP ’7068
II. ANALYSIS
A. Claim Construction
In an inter partes review, the Board interprets a claim term in an
unexpired patent according to its broadest reasonable construction in light of
the specification of the patent in which it appears. 37 C.F.R. § 42.100(b); In
re Cuozzo Speed Techs., LLC, 793 F.3d 1268, 1275–79 (Fed. Cir. 2015),
cert. granted sub nom. Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 890
(mem.) (2016). Under that standard, and absent any special definitions, we
assign claim terms their ordinary and customary meaning, as would be
understood by one of ordinary skill in the art at the time of the invention, in
the context of the entire patent disclosure. In re Translogic Tech., Inc., 504

4 European Patent EP 0,787,813 B1. Ex. 1003.
5 Swiss Patent CH 165,893. Ex. 1002.
6 Japanese Patent App. Pub. JP 1988-282241 . Ex. 1004.
7 Japanese Patent Publication H11-222650. Ex. 1005.
8 Japanese Patent App. Pub. H04-147706. Ex. 1006.
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F.3d 1249, 1257 (Fed. Cir. 2007). An inventor may rebut that presumption
by providing a definition of the term in the specification with reasonable
clarity, deliberateness, and precision. In re Paulsen, 30 F.3d 1475, 1480
(Fed. Cir. 1994). In the absence of such a definition, limitations are not to
be read from the specification into the claims. In re Van Geuns, 988 F.2d
1181, 1184 (Fed. Cir. 1993). Only terms which are in controversy need to
be construed, however, and then only to the extent necessary to resolve the
controversy. Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803
(Fed. Cir. 1999).9
For the reasons provided below, we construe the challenged process
claims 1–4 to require carbidic constituents and by weight 2–10% Mo+W+V
(molybdenum + tungsten + vanadium). Additionally, we construe the
challenged process claims as requiring the setting of the thermal
conductivity at room temperature to more than 42 W/mK (watts per square
meter of surface area). Based on the evidence of record, however, we hold
that that the claims are not limited to particular heat-treatment (thermo-
mechanical) processing conditions. Tr. 53:24–56:5. We also hold that the
claims are not limited to specific amounts of chromium, carbon, combined
amounts of carbon and nitrogen, or combined amounts of carbon, nitrogen
and boron. Pet. 6. Specifically, Petitioner has failed to demonstrate on this
record that we are required to read limitations into the claims from the
specification. Comark Commc'ns, Inc. v. Harris Corp., 156 F.3d 1182, 1186

9 In considering the meaning and patentability of the challenged claims, we
do not address indefiniteness or enablement under 35 U.S.C. § 112.
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(Fed. Cir. 1998) (“[F]ine line between reading a claim in light of the
specification, and reading a limitation into the claim from the
specification.”).
In the instant proceeding, BÖHLER Edelstahl proposes a construction
of the process steps in claims 1–4 in terms of the composition of the hot-
work steel as set forth in the ’056 patent. BÖHLER Edelstahl states that
[a]ccording to the ’056 specification, the claimed process for
selecting a thermal conductivity of a hot-work steel, and the
individual process steps, are carried out by selecting a specific
composition of the steel. Aside from selecting the steel
composition, the ’056 specification enables no other way to carry
out the process steps.
Pet. 4. For instance, BÖHLER Edelstahl asserts that the ’056 patent
Specification provides no measuring techniques, values, or range of values
for electron density, phonon density, mean free path length for phonon and
electron flow, surface fraction of carbidic constituents, thermal conductivity
of carbidic constituents, particular surface fraction of matrix material,
thermal conductivity of matrix material, or volume fraction of carbidic
constituents. Id. at 8–9.
Specifically, BÖHLER Edelstahl posits that the following steps of the
process of claim 1 should be construed to mean a particular hot-work steel
composition: (1) step 2 — “metallurgically creating an internal structure of
the steel in a defined manner such that carbidic constituents thereof have at
least one of a defined electron and phonon density and a crystal structure
thereof having a mean free length of a path for a phonon and electron flow
being determined by specifically created lattice defects;” and (2) step 3 —
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“selecting: (a) a surface fraction and thermal conductivity of the carbidic
constituents and a particular surface fraction and thermal conductivity of a
matrix material containing the carbidic constituents; or (b) a volume fraction
and thermal conductivity of the carbidic constituents and thermal
conductivity of the matrix material containing the carbidic constituents.”
Ex. 1001, 21:64–22:11. To construe these limitations, BÖHLER Edelstahl
relies on the statement in the ’056 patent that carbon and chromium in the
solid solutions state lead to matrix distortion, and therefore, a matrix
depleted of carbon and chromium increases the thermal conductivity of the
steel. Pet. 6 (citing Ex. 1001, 6:14–28).
Because the amounts of Mo, W, and V are separately recited in
claim 1 and no values or ranges are provided for electron density, phonon
density, mean free path length for phonon and electron flow, surface area, or
volume fraction (which depends on the steel composition), BÖHLER
Edelstahl asserts that these steps are limited to the remaining elements of the
hot-work steel composition other than Mo, W, and V, and correspond to
“providing said hot-work steel composition further including less than 2%
by weight Cr and any of (a) 0.26 to 0.55% by weight C, (b) 0.25 to 1.00% by
weight C and N in total, or (c) 0.25 to 1.00% by weight C, N and B in total.”
Pet. 6, 8–9, 13.
BÖHLER Edelstahl asserts that this same hot-work steel composition
also corresponds to the following steps in claim 4: (1) step 2a —
“metallurgically creating an internal structure of the steel in a defined
manner such that it has in its carbidic constituents an increased electron and
phonon density and/or which has a result of a low defect content in a crystal
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structure of carbides and of a metallic matrix surrounding them an increased
mean free length of a path for a phonon and electron flow;” and (2) step 3 —
“selecting: (a) a surface fraction and thermal conductivity of the carbidic
constituents and a particular surface fraction and thermal conductivity of a
matrix material containing the carbidic constituents; or (b) a volume fraction
and thermal conductivity of the carbidic constituents and thermal
conductivity of the matrix material containing the carbidic constituents.”
Ex. 1001, 22:26–60; see Pet. 7–10, 14. As support, BÖHLER Edelstahl
notes that the recited optional “low defect content in a crystal structure of
carbides and of a metallic matrix surrounding them,” requires at least some
defects in the crystal structure, which is minimized by reducing the
chromium content. Pet. 7–8 (quoting Ex. 1001, 10:16–27).
As to the fourth and final step that claims 1 and 4 have in common,
“setting the thermal conductivity of the steel at room temperature to more
than 42 W/mK,” BÖHLER Edelstahl posits that this limitation should be
construed as follows:
[A] fair construction of process step (4) is to provide a hot-work
steel composition (already limited by the compositions defining
process steps (1)–(3)) that is further limited by the additional
ingredients and ranges defining the three operable compositions:
providing said hot-work steel composition, wherein the
content of W and Mo in total amounts to at least 1.8% by
weight and the amount of V is from 1 to 4% by weight,
further including carbide-forming elements Ti, Zr, Hf, Nb,
Ta with a content of from 1 to 3% by weight individually
or in total,
0 to 6% by weight Co,
0 to 1.6% by weight Si,
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0 to 2% by weight Mn,
0 to 2.99% by weight Ni,
0 to 1% by weight S, and
remainder, iron and unavoidable impurities.
Pet. 10–11, 13–15. As support, BÖHLER Edelstahl notes that the ’056
patent Specification describes how thermal conductivity is affected not only
by the type and amount of carbide forming elements and the amount of
chromium, but also the additional elements in the matrix. Pet. 10 (quoting
Ex. 1001, 9:56–65). BÖHLER Edelstahl concludes that “[a]side from
selecting a specific steel composition, the ’056 specification reveals no
specific manufacturing techniques needed to practice the claimed process.”
Pet. 12. BÖHLER Edelstahl’s constructions for the two independent claims
1 and 4 are identical.
Finally, BÖHLER Edelstahl proposes a construction of the limitation
of claim 2, “setting the thermal conductivity of the steel at room temperature
to more than 48 W/mK,” as requiring a chromium content of 0.5% by weight
or less, and the limitation of claim 3, “setting the thermal conductivity of the
steel at room temperature to more than 55 W/mK,” as requiring a chromium
content of 0.3% by weight or less. Pet. 12.
Rovalma responds that the challenged claims are process claims, not
composition claims, and should be construed as such, not limited to a
particular composition. Specifically, Rovalma states that
[t]he thermal conductivity of the material is set in accordance
with the claimed invention, namely, by selecting the components
Mo+W+V, by metallurgically creating the specific internal
structure to define the conductance behavior of the carbidic
constituents, by selecting either a given surface fraction and
thermal conductivity of the carbidic constituents or the relative
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volume fractions and thermal conductivity of the carbidic
constituents and the matrix, and by setting the thermal
conductivity to more than 42 W/mK.
Prelim. Resp. 6–7. Rovalma asserts that the thermal conductivity of a steel
having carbidic constituents can be set by acting on the internal structure of
the steel regardless of the specific steel composition. Id. at 6, 10, 13. “In
other words, the thermal conductivity of a steel having a specific
composition can be set to different values by following the process steps
claimed in the ’056 Patent.” Id. at 13. Consistent with their plain language,
we construe the “setting” step of the challenged claims as requiring the
setting of the thermal conductivity at room temperature to more than, e.g.,
42 W/mK.
Rovalma further argues that the step of “metallurgically creating an
internal structure of the steel in a defined manner” should be construed to
mean “heat treating the steel . . . under specific conditions selected to
achieve the desired internal structure[,]” “and hence thermal conductivity.”
PO. Resp. 38, 39. Rovalma argues that “the ‘defined manner’ will differ
based on the steel composition used, the desired thermal conductivity, and
the specific hot-work application for the tool steel.” Id. at 39–40.
In support of this construction, Rovalma asserts that one of ordinary
skill in the art would have known that chemical “composition is just one
factor that affects the steel’s final internal structure. It is a fundamental
principle that the thermal processing conditions applied to the tool steel will
affect the internal structure of the finished tool steel.” Id. at 39 (citing Ex.
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2006 43); see Tr. 49:18–51:16, 52:20–23, 53:24–54:6.10 Rovalma further
argues that the subsequent “selecting” and “setting” steps of the challenged
claims further inform the “defined manner” in which the steel is treated to
create the final internal structure and thermal conductivity. PO. Resp. 46–
47. With the limited exception of Table 6, discussed above, the ’056
Specification discloses no specific manufacturing protocol for the practice of
the invention. Consistent with this lack of guidance regarding how to treat
steel to create the desired internal structure and thermal conductivity, we do
not find the claims limited to particular heat-treatment (thermo-mechanical)
processing conditions.
Prior art cited by Rovalma, however, underscores that one of ordinary
skill in the art recognized that thermal processing conditions affect internal
structure and, thus, thermal properties. Bayati and Elliot, for example, teach
that heat transport “depends on lattice defects, microstructure, impurities,
and the processing of the metal or alloy,” and that matrix structure “play[s] a
significant role” in determining thermal conductivity. Ex. 2009, 265; see
also id. (noting that matrix structure changes “which occur during heating
and promote ferrite formation (such as tempering of martensite and the stage
II reaction in the austempered matrix structure) increase the thermal
conductivity” of ductile iron); id at 266 (“The results for the ductile iron

10 Rovalma further demonstrates this principle using the Netzsch Report (Ex.
2003) (showing that thermo-mechanical processing of a steel composition
can affect microstructure and thermal conductivity). See PO Resp. 25–27.
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show that the matrix structure makes a significant contribution to the thermal
conductivity”).
Moreover, as discussed at pages 2–4 of the Patent Owner Response,
the generation of carbides in metal matrices was well understood such that
by “[u]sing equilibrium phase diagrams and knowing the effects of
processing operations, those skilled in the art can predict which carbides will
be present in a given steel and their microstructural distributions following
various heat treatments.” PO. Resp. 4 (citing Exs. 2005,11 200612).
Similarly, readily available tools such as the Thermo-Calc software package
enabled “those skilled in the art to model the formation and precipitation of
carbides in multi-component alloys.” Id. at 5 (citing Ex. 2006).
Accordingly, we accept Rovalma’s assertion that at the time of the
invention, “one skilled in the art could model the formation and precipitation
of carbides within steel as a function of time and temperature.” PO Resp. 5,
n.1.
BÖHLER Edelstahl, relying on Table 6 and column 17, lines 43
through 46 of the Specification, argues that the ‘056 patent Specification
teaches that the basic setting of thermal conductivity is obtained by chemical
composition, and only an additional fine setting is achieved by different
thermal treatments.” Reply 9–11. To the extent this may be true, the
challenged claims merely require that the chemical composition of the steel

11 ASM Materials Engineering Dictionary, pages 57, 156, 448, 449, 477,
490, and 491 (J. R. Davis ed., 1992).
12 George Roberts et al., Tool Steels 45–107 (5th ed. 1998).
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include carbidic constituents and 2–10% by weight of molybdenum,
tungsten, and/or vanadium. In the present case, we are not persuaded that
additional compositional limitations should be imported into the claims. See
SuperGuide Corp. v. DirecTV Enters., Inc., 358 F.3d 870, 875 (Fed. Cir.
2004). (“Though understanding the claim language may be aided by the
explanations contained in the written description, it is important not to
import into a claim limitations that are not a part of the claim. For example,
a particular embodiment appearing in the written description may not be
read into a claim when the claim language is broader than the embodiment.”)
Read in the context of the understanding of one of ordinary skill in the
art at the time of the invention, we do not agree with BÖHLER Edelstahl
that the claims should be construed to correspond to specific compositions
set forth in the Specification of the ’056 patent, or that the claims are limited
to specific amounts of chromium, carbon, combined amounts of carbon and
nitrogen, or combined amounts of carbon, nitrogen and boron. Rather, we
construe the step of “metallurgically creating an internal structure of the
steel in a defined manner” as “heat treating the steel under conditions
selected to achieve the internal structure defined by the ‘selecting’ steps, and
which result in the recited thermal conductivity of the steel at room
temperature.”
B. Obviousness of Claims 1–4 over EP ’813 in Combination
With Other References
BÖHLER Edelstahl asserts that claims 1–4 are unpatentable under
35 U.S.C. § 103(a) as obvious over the EP ’813 used in individual
combination with four other references. Pet. 32–59.
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a. Overview of Asserted References
EP ’813 discloses low chromium, heat-resistant ferritic steels having
advantages including “higher toughness, thermal conductivity and
weldability” as compared to high chromium ferritic steels. Ex. 1003, 2:16–
20, 4:7–16. Tables 2 and 3 of the reference disclose the chemical
composition of low chromium steels having a carbon component. Id. 10–11.
Example 8 comprises, by weight, 1.07% chromium, 0% molybdenum,
2.61% tungsten, and 0.21% vanadium. Id. at 10. Example 32 comprises, by
weight, 0.98% chromium, 1.05% molybdenum, 1.01% tungsten, and 0.23%
vanadium. Id. at 11. Accordingly, we find that EP ’813 Examples 8 and 32
each include “carbidic constituents” (i.e., carbon in conjunction with carbide
formers such as chromium, tungsten, and vanadium) and, “by weight, 2–
10% Mo+W+V” as set forth in the challenged claims. See PO. Resp. 58
(admitting that “the prior art disclosed ‘providing a hot-work steel, including
carbidic constituents and, by weight, 2-10% Mo+W+V’—step 1 of the
challenged claims”).
As with EP ’813, CH ’893 discloses low-chromium steel
compositions having valuable characteristics including “relatively high hot
tensile strength, toughness and resistance against temperature variations.”
Ex. 1002, p. 1 ¶3, p. 3, ¶ 6. The second embodiment disclosed on page 4 of
the reference comprises 0.27% carbon, 3.32% tungsten, and no chromium,
molybdenum or vanadium. CH ’893 thus discloses the benefit of high
thermal conductivity (“resistance against temperature variations”) and at
least one embodiment comprising “carbidic constituents and, by weight, 2–
10% Mo+W+V” as set forth in the challenged claims.
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JP ’241 discloses low chromium steels having, e.g., improved high
temperature abrasion. Ex. 1004, 2–3. Claim 2 of the reference encompasses
a steel composition comprising, by weight, “C: 0.10–0.40%, Si: 0.10–
1.00%, Mn: 0.20–2.00%, Cr: less than 0.95%, Mo: 0.50–3.50%, W: 0.50–
3.50% and Nb: 0.10–1.00%, and further containing more than one or two
variations selected from Ni: 0.50-3.50%, Co: 0.50–3.50% and V: 0.10–
1.00%.” Id. at 2, claim 2. JP ’241 thus discloses steel compositions
comprising “carbidic constituents and, by weight, 2–10% Mo+W+V” as set
forth in the challenged claims.
JP ’706 discloses a low chromium steel plug compositions B and C
for seamless pipe manufacturing comprising 0.30% carbon, 0.5% chromium,
1.50% molybdenum, 2.00% and 3.00% tungsten, respectively, and no
vanadium. Ex. 1006, Table 1. Accordingly, JP ’706 discloses steel
compositions comprising “carbidic constituents and, by weight, 2–10%
Mo+W+V” as set forth in the challenged claims.
JP ’650 discloses alloy steel having excellent forgeability and wear
resistance comprising, e.g., M6C carbides and amounts of molybdenum,
tungsten, and vanadium within the claimed range. Ex. 1005 ¶ 4. As set
forth in Table I of the reference, composition No. 2 comprises 0.31%
carbon, 0.03% chromium, 6.01% molybdenum, 0.87% tungsten, and 3.04%
vanadium. Id. ¶ 16. Accordingly, JP ’650 discloses steel compositions
comprising “carbidic constituents and, by weight, 2–10% Mo+W+V” as set
forth in the challenged claims.
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b. Application of Asserted References in View of Knowledge in the
Art
Rovalma argues that the ’056 patent “teaches you to go after
microstructures [as shown in Figure 1] that have carbides that have high
thermal conductivity, maximize their proportion in the overall final
structure, and eliminate some of the defects in the matrix.” Tr. 50:4–24.
According to Rovalma, “[o]nce you know the types of carbides you want
and the types of crystalline structures in the various phases of steel you
want, that can be predicted based on this simulation software that’s built on
years of experimental analysis of the different phases and so on.” Tr. 75:2–
8. In other words, concludes Rovalma, once the desired microstructure is
known, “[t]he simulation software would tell you how hot you have to heat
during austenitization, how quickly should you quench it.” Id. at 75:13–15.
Although the asserted references establish that steel formulations
having the chemical composition required by the challenged claims were
well known, Rovalma argues that:
[n]one of the references consider that the thermal conductivity of
a steel is a resultant characteristic of the steel’s microstructure,
or more specifically, that it can be determined as a function of
the area (or volume) fractions of the carbide and of the matrix
material, together with the thermal conductivity of the matrix and
the thermal conductivity of the carbides. Even more importantly,
none of the references suggest setting the thermal conductivity
of a hot-work steel by manipulating the steel’s microstructure in
a defined manner.
PO. Resp. 56.
We do not find Rovalma’s argument persuasive.
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As noted above, one of ordinary skill in the art at the time of the
invention would have recognized that thermal processing conditions affect
internal structure and, thus, thermal properties of steel. Bayati and Elliot, for
example, teach that heat transport “depends on lattice defects,
microstructure, impurities, and the processing of the metal or alloy,” and that
matrix structure “play[s] a significant role” in determining thermal
conductivity. Ex. 2009, 265; Tr. 67:3–13. As Rovalma further explains at
page 7 of its Patent Owner Response,
Heat is transported through metals by phonons and free electrons.
Ex. 2009 at 265. In pure metals, heat transfer is primarily
influenced by the metal’s free electrons. Id. Lattice defects and
impurities in a metal or alloy scatter the electrons within the
metallic matrix, thus reducing the rate that heat can transfer
through the metal. Id. In non-metals such as carbides, thermal
conductivity is primarily influenced by vibration within the
lattice of atoms or molecules (these vibrations are referred to by
the quantum mechanical term “phonon”). Id.; Paper 14 at 3.
Concurrent with this understanding of heat transfer through metallic
matrices and metal carbide inclusions, one of ordinary skill in the art would
also have understood that “optimization of the microstructure has been
known for a long time.” Tr. 66:9–16; see PO Resp. 5 (citing Ex. 2006); id.
at n.1). Thus, “[u]sing equilibrium phase diagrams and knowing the effects
of processing operations, those skilled in the art [could] predict which
carbides will be present in a given steel and their microstructural
distributions following various heat treatments.” PO Resp. 4 (citing Exs.
2005, 2006). Similarly, “readily available thermo-chemical databanks and
software programs such as Thermo-Calc, allow[ed] those skilled in the art to
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model the formation and precipitation of carbides in multi-component
alloys.” Id. at 5 (citing Ex. 2006) (referencing footnote 1); see Tr. 75:10–15.
Because EP ’813 and other asserted references disclose steel
compositions comprising the claimed “carbidic constituents and, by weight,
2-10% Mo+W+V,” along with the desirability of steels having high thermal
conductivity, the skilled artisan would have had reason to increase the
thermal conductivity of these compositions. Given the understanding in the
art regarding heat transfer through metallic matrices and entrained metal
carbides, and the ability to model the effects of thermal processing on steel
alloy microstructure, one of ordinary skill in the art would have had a
reasonable expectation of success in arriving at the claimed invention.
Having thus “set” the claimed “thermal conductivity of the steel at room
temperature [of] more than [e.g.,] 42 W/mK,” the skilled artisan would have
at least inherently completed the “selecting” steps set forth in the challenged
claims.
Accordingly, we find claims 1–4 of the ’056 patent obvious over the
asserted prior art as read in light of the knowledge of the ordinarily skilled
artisan.
III. PATENT OWNER’S OBJECTIONS TO PETITIONER’S EXHIBITS
Rovalma objects to Exhibits 1013 (original), 1013 (corrected), and
1014 on grounds relating to the certification of translations. Paper 27. We
dismiss Rovalma’s objections as moot because we do not rely on any of the
objected-to Exhibits in our Final Decision.
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IV. CONCLUSION
Petitioner has demonstrated by a preponderance of the evidence that
claims 1–4 of the ’056 patent are unpatentable under 35 U.S.C. § 103(a) as
obvious over EP ’813 used in individual combination with CH ’893, JP
’241, JP ’650, or JP ’706.
V. ORDER
For the foregoing reasons, it is
ORDERED that claims 1–4 of the ’056 patent are held unpatentable;
FURTHER ORDERED that Patent Owner’s Objections to Petitioner’s
Exhibits are dismissed as moot; and
FURTHER ORDERED that because this is a final decision, parties to
the proceeding seeking judicial review of the decision must comply with the
notice and service requirements of 37 C.F.R. § 90.2.

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PETITIONER:

Maxwell Petersen
Maxwell.Petersen@lewisbrisbois.com

Thomas Dougherty
Thomas.Dougherty@lewisbrisbois.com

PATENT OWNER:

Marc Vander Tuig
mvandertuig@senniger.com

Robert Evans
revans@senniger.com

John Schroeder
jschroeder@senniger.com