DETAILED ACTION
Response to Amendment
The Amendment filed 01/28/2026 has been entered. Claims 1-20 remain pending in the application. Claims 7-20 have been withdrawn due to a restriction requirement. The nonstatutory double patenting rejections over copending Application No. 18/043,217 previously set forth in the Non-Final Rejection mailed 09/29/2025 is withdrawn since the copending steel is martensitic while the instant steel has a bainitic and ferritic microstructure. The Examiner agrees with Applicant’s explanation regarding the terms “A50” and “R/T” of claim 6 (remarks, pages 8-9) and the 112(b) rejections previously set forth in the Non-Final Rejection mailed 09/29/2025 are withdrawn.
Claim Interpretation
Regarding claim 1, the terms “comprising” and “contains” are interpreted as open-ended. The transitional term "comprising", which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. See MPEP 2111.03. In this case, the claimed chemical composition and microstructure are interpreted as not excluding additional, unrecited elements.
Regarding the longitudinal yield strength of claim 6, the term “longitudinal yield strength” is interpreted as a yield strength obtained from testing a specimen along the rolling direction used in the manufacturing process of the claimed steel.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-6 are rejected under 35 U.S.C. 103 as being unpatentable over CN 104513930 A of Zhang (as cited in IDS mailed 01/20/2023, with reference to English machine translation attached).
Regarding claims 1-6, Zhang teaches ultra-high strength hot-rolled multiphase steel plates and strips with good bending and hole expansion properties (Abstract, reads on claimed steel plate). Zhang teaches the steel can be used to manufacture products such as automobile chassis, suspension parts, and bumpers. One of ordinary skill in the arts understands a torsion beam is a structural part used in the automotive industry, including in chassis and suspension parts.
Zhang therefore reads on the limitation steel plate for a torsion beam of claim 1.
Additionally, the limitation “for a torsion beam” has been given little patentable weight because the recitation occurs in the preamble. A preamble is generally not accorded patentable weight where it merely recites the purpose of a process or the intended use of a structure, and where the body of the claim does not depend on the preamble for completeness but, instead, the process steps or structural limitations are able to stand alone. See In re Hirao, 535 F.2d 67, 190 USPQ 15 (CCPA 1976) and Kropa v. Robie, 187 F.2d 150, 152, 88 USPQ 478, 481 (CCPA 1951). In the instant case, the preamble merely recites the intended use of the composition, i.e. for a torsion beam, wherein the prior art can meet this future limitation by merely being capable of such intended use.
List 1
Instant claims (mass%)
Zhang - Steel H-1 (wt%)
Zhang – Broader disclosure (wt%)
C
0.04-0.085
0.09
0.07-0.14
Si
0.02-0.5
0.39
0.1-0.4
Mn
1.3-1.8
1.51
1.55-2.00
Cr
0.15-0.5
0.19
0.15-0.5 (at least one of Cr and Mo)
Mo
0.12-0.30
0.20
0.15-0.5 (at least one of Cr and Mo)
Nb
≤ 0.058
-
≤ 0.07 (at least one from Nb, Ti, V)
V
≤ 0.15
0.16
0.10-0.20 (at least one from Nb, Ti, V)
Ti
≤ 0.02
0.021
0.02-0.15 (at least one from Nb, Ti, V)
Al
0.02-0.1
0.026
0.01-0.05
P
≤ 0.02
0.011
≤ 0.015
S
≤ 0.005
0.002
≤ 0.004
N
≤ 0.005
0.002
≤ 0.005
Fe and inevitable impurities
Balance
Remainder
Remainder (“and unavoidable impurities”)
2Nb+V
0.096-0.17
0.16 (calculated)
0-0.34
0.5Cr+Mo
0.3-0.55 (claim 2)
0.3 (calculated)
0.075-0.75
CEIIw
≤ 0.50 (claim 3)
0.45 (calculated)
0.39-0.71
Bainite + ferrite
≥ 90 vol%
> 95 vol% (claim 4)
Broader disclosure
At least 80% bainite
Bainite
55-85 vol%
Broader disclosure
At least 80%
Pearlite and/or martensite
≤ 10 vol% (implicit – claim 5)
Broader disclosure
“a small amount of ferrite, martensite and retained austenite”
Longitudinal yield strength
≥ 620 MPa (claim 6)
715 MPa
≥ 700 MPa
Tensile strength
≥ 760 MPa (claim 6)
805 MPa
≥ 800 MPa
A50 elongation
≥ 16% (claim 6)
19.5%
13.3-19.5% (Inventive examples in Table 2 including G-1 and H-1)
180° cold bending property R/T
≥ 1.05 (claim 6)
0a
0a
Zhang teaches a steel with a chemical composition (H-1 in Table 1, Abstract, [0012], [0017]-[0025]), microstructure ([0009]), yield strength (H-1 in Table 2, [0009]), tensile strength (H-1 in Table 2, [0009]), and A50 elongation (H-1 in Table 2; Inventive examples in Table 2 including G-1 and H-1) overlapping with the claimed steel, as shown in List 1. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
Zhang therefore reads on the limitation comprising the following chemical components in percentage by mass:0.04-0.085% of C, 0.02-0.5% of Si, 1.3-1.8% of Mn, 0.15-0.5% of Cr, 0.12-0.30% of Mo, 0.058% or less of Nb, 0.15% or less of V, 0.02% or less of Ti, 0.02-0.1% of Al, 0.02% or less of P, 0.005% or less of S, and 0.005% or less of N, the balance being Fe and inevitable impurities, wherein the steel plate comprises one or two of Nb and V of claim 1, wherein a microstructure of the steel plate contains bainite and ferrite, and a volume fraction of the bainite is 55-85% of claim 1, wherein the microstructure of the steel plate further contains pearlite and/or martensite of claim 5, wherein the steel plate has a longitudinal yield strength of 620 MPa or more, a tensile strength of 760 MPa or more, an A50 elongation of 16% or more of claim 6.
Zhang further teaches a steel H-1 with a chemical composition, microstructure, yield strength, tensile strength, and A50 elongation lying with the claimed ranges with the exception of C, V, and Ti, as shown in List 1. Regarding the C, V, and Ti content, steel H-1 has 0.09% C, 0.16% V and 0.021% Ti, which is infinitesimally close to the claimed top value of 0.085% C, 0.15% V and 0.02% Ti respectively. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I.
Additionally or alternatively, Zhang teaches a carbon content of 0.07% to 0.14% to meet strength, elongation and porosity requirements ([0017]). Zhang teaches a vanadium content of 0.10 to 0.20% to obtain a precipitation strengthening effect ([0023]). Zhang teaches a titanium content of 0.02 to 0.15% to obtain a grain refinement or precipitation strengthening effect and improves strength without reducing elongation and porosity ([0022]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the C, V, and Ti compositions of steel H-1 of Zhang, such as within claimed ranges, to obtain desired strength, elongation, porosity, and strengthening effects, as taught by Zhang.
In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
While Zhang does not explicitly disclose values for 2Nb+V of claim 1, 0.5Cr+Mo of claim 2, and a carbon equivalent of claim 3, one can perform the calculations which result in values lying within or overlapping with the claimed ranges as shown in List 1. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
Zhang therefore reads on the limitation the amount of Nb and V satisfies the following formula: 0.096% ≤ 2Nb+V ≤ 0.17% of claim 1, wherein the chemical components of the steel plate satisfy 0.3% ≤ 0.5Cr+Mo ≤ 0.55%, wherein the element symbols in the formula denote the weight percentage of the corresponding elements in the steel plate of claim 2, wherein the chemical components of the steel plate satisfy: a carbon equivalent CEIIw ≤ 0.50%, wherein CEIIw =%C+%Mn/6+%(Cr+Mo+V)/5+%(Ni+Cu)/15, wherein the element symbols in the formula denote the weight percentage of the corresponding elements in the steel plate of claim 3.
Regarding the total volume fraction of bainite and ferrite of claim 1, Zhang teaches the microstructure is at least 80% bainite and a small amount of ferrite, martensite and retained austenite, wherein the bainite is mainly lower bainite ([0009]). Zhang teaches coiling at a temperature of 430-550°C to obtain an appropriate amount of carbides increasing the strength and reducing the strength difference between bainite, small amount of ferrite, and small amount of martensite in the microstructure ([0011], [0032], [0039]). Given the overlapping chemical composition, bainite content, tensile strength, yield strength, elongation, and processing, one of ordinary skill in the art would reasonably expect the steel of Zhang to necessarily possess the claimed total volume fraction of bainite and ferrite despite not explicitly disclosing or measuring the amount of ferrite.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP § 2112.01 I. “Products of identical chemical composition can not have mutually exclusive properties.” A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). See MPEP § 2112.01 II. Therefore, it is expected that the steel of the prior art possesses the properties as claimed in the instant claims since a) the claimed and prior art products are identical or substantially identical in composition (see compositional analysis above), b) the claimed and prior art products are identical or substantially identical in structure (see microstructure analysis above), and c) the claimed and prior art products are produced by identical or substantially identical processes (both have coiling steps with overlapping temperatures). Since the Office does not have a laboratory to test the reference alloy, it is applicant’s burden to show that the reference alloy does not possess the properties as claimed in the instant claims. See In re Best, 195 USPQ 430, 433 (CCPA 1977); In re Marosi, 218 USPQ 289, 292-293 (Fed. Cir. 1983); In re Fitzgerald et al., 205 USPQ 594 (CCPA 1980).
One of ordinary skill in the art would reasonably expect the steel of Zhang to necessarily possess the claimed total volume fraction of bainite and ferrite despite not explicitly disclosing or measuring the amount of ferrite or total of bainite and ferrite since the steel of Zhang has overlapping chemical composition, bainite content, tensile strength, yield strength, elongation, and processing with the instant invention.
Zhang therefore reads on the limitation wherein a total volume fraction of the bainite and the ferrite is 90% or more of claim 1.
Zhang therefore reads on all the limitations of claims 1-5.
Regarding the cold bending property of claim 6, Zhang teaches the ultra-high strength hot-rolled multiphase steel with good bending properties and that has a 180° cold bending performance of 0a ([0009], [0044], reads on claimed 180° cold bending property). However, Zhang does not explicitly disclose a R/T of 1.05 or more.
Given the overlapping chemical composition, microstructure, tensile strength, yield strength, and elongation, one of ordinary skill in the art would reasonably expect the steel of Zhang to necessarily possess the claimed R/T of 1.05 or more despite not explicitly measuring or disclosing it.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP § 2112.01 I. “Products of identical chemical composition can not have mutually exclusive properties.” A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). See MPEP § 2112.01 II. Therefore, it is expected that the steel of the prior art possesses the properties as claimed in the instant claims since a) the claimed and prior art products are identical or substantially identical in composition (see compositional analysis above), and b) the claimed and prior art products are identical or substantially identical in structure (see microstructure analysis above). Since the Office does not have a laboratory to test the reference alloy, it is applicant’s burden to show that the reference alloy does not possess the properties as claimed in the instant claims. See In re Best, 195 USPQ 430, 433 (CCPA 1977); In re Marosi, 218 USPQ 289, 292-293 (Fed. Cir. 1983); In re Fitzgerald et al., 205 USPQ 594 (CCPA 1980).
One of ordinary skill in the art would reasonably expect the steel of Zhang to necessarily possess the claimed R/T of 1.05 or more despite not explicitly disclosing or measuring the R/T value since the steel of Zhang has overlapping chemical composition, microstructure, tensile strength, yield strength, and elongation with the instant invention.
Zhang therefore reads on the limitation 180° cold bending property R/T of 1.05 or more of claim 6.
Additionally, or alternatively, it is well known in the art that steels can have a variety of shapes, and consequently various radii and thicknesses, to form complex automotive structural parts such as automotive chassis, suspension parts, and others (as evidenced by Zhang, [0005]). Neither the instant claims nor the instant specification provide evidence as to why the radius and thickness of the claimed steel meeting an R/T value of 1.05 or more is significant. The change in configuration or shape of a device is obvious absent persuasive evidence that the particular configuration is significant (emphasis added). In re Dailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966). It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the shape of the steel of Zhang, such as to that of a beam which is well-known in the art as a structural part in the automotive industry, and adjusting the radius (R) and thickness (T) of the steel of Zhang, such as within the claimed R/T ranges, to meet the requirements of a particular structural part for the automotive industry.
Response to Arguments
Applicant’s arguments, see pages 9-11, filed 01/28/2026, with respect to the rejections of claims 1-6 under 35 U.S.C. 103 have been fully considered and are persuasive. Applicant argues that Drillet explicitly excludes ferrite or at least suppresses the formation of ferrite (remarks, page 9). In response, amended claim 1 now requires a total of bainite and ferrite is 90% or more and a volume fraction of bainite is 55-85%. The broadest reasonable interpretation of “bainite” includes ferrite since one of ordinary skill in the art understands bainite is a mixture of ferrite and cementite. Nevertheless, Drillet does not teach microstructures that meet the new limitations simultaneously since 90% bainite of Drillet would meet the claimed total of bainite and ferrite but would exceed the claimed volume fraction of bainite. Therefore, the rejection has been withdrawn. However, upon further consideration, a new grounds of rejection is made in view of CN 104513930 A of Zhang.
Applicant’s arguments with respect to claims 1-6 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAYELA ALDAZ whose telephone number is (571)270-0309. The examiner can normally be reached Monday -Thursday: 10 am - 7 pm and alternate Friday: 10 am - 6 pm.
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/M.A./Examiner, Art Unit 1733
/REBECCA JANSSEN/Primary Examiner, Art Unit 1733
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