Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 20 April 2026 has been entered.
Status of Claims
Responsive to the amendment filed 20 April 2026 claim 1 is amended and claim 6 is cancelled. Claims 1-5 and 7-11 are currently under examination.
Status of Previous Rejections
Responsive to the amendment filed 20 April 2026 new grounds of rejection are presented.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1-5 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 5100612 A (hereinafter “Obata”) in view of US 20160047008 A1 (hereinafter “Margaria”), and Olawale, et. al, Processing Techniques and Productions of Ductile Iron: A Review, International Journal of Scientific & Engineering Research, Volume 7, Issue 9, September-2016, p. 397-423 (hereinafter “Olawale”).
Regarding claim 1, Obata teaches a method of making spheroidal cast iron (see abstract or OBJECT AND SUMMARY OF THE INVENTION). Obata teaches that the desired cast irons are high in sulfur (see cols 1-2), meeting the limitation of “increasing sulfur content.” Obata teaches that a rare earth alloy element is added to the molten iron either before or simultaneous to addition of a spheroidizing agent (see abstract or OBJECT AND SUMMARY OF THE INVENTION). Obata teaches that a sulfur containing material is added to the molten iron to adjust the rare earth content (see abstract or OBJECT AND SUMMARY OF THE INVENTION).
Obata describes the process at cols 3-4. Obata teaches that the sulfur reacts with the RE in order to form a sulfide, which will nucleate the spheroidal graphite (col 4). Obata teaches that this prevents cementite (col 4). Obata further describes examples such as EXAMPLE 1. Obata teaches that the elements re added to a furnace. Either the furnace or ladle meets the limitation of a “nodularizing unit.”
Obata does not teach adding the RE to the nodularizing unit prior to the molten metal. Obata teaches adding RE to molten metal (Example 1). Obata does not teach to have the RE on a surface of a nodularizer. Obata envisions a single prealloy (Example 1).
Margaria teaches a method of treating a liquid cast iron with an inoculant, into which the growth of graphite is promoted (See abstract, BRIEF SUMMARY). Margaria teaches that the inoculant includes fusible support particles, with a surface particle that promotes the graphite (See abstract, BRIEF SUMMARY). Margaria teaches that the surface particles may include rare earths (see [0041]). Margaria teaches that the support may be an alloy such as FeSi (see [0032]-[0037] and [0047]). FeSi meets all limitations of a “nodularizer.” Margaria teaches that the inventive inoculant provides a low sensitivity to the cast iron composition, and allows for good uniformity when a part with varying thicknesses is cast (see BRIEF SUMMARY).
It would have been an obvious matter to the skilled artisan to have practiced the method of Obata, but to have used a powder with the rare earths on the surface of a FeSi alloy as taught by Margaria, because Margaria teaches that the inventive inoculant provides a low sensitivity to the cast iron composition, and allows for good uniformity when a part with varying thicknesses is cast (see BRIEF SUMMARY).
Olawale provides a review of Ductile iron production methods (see title, Introduction). Olawale teaches inoculation, such as with Nodularizers like FeSi (See 2.1 Graphite Nodularizer and Inoculants of Ductile Iron and 2.2 Graphite Nodularization with Magnesium). Olawale teaches various means of introducing the inoculant to the iron (see pp. 400-415). Olawale teaches that for a ladle or for a tundish, the “sandwich” method of applying the inoculant and a cover to the ladle or tundish is provided (See pp 406-409 and Figs 9, 10, and 11). Olawale teaches that this technique delays reaction time and improves the efficiency of the process (see p. 406).
It would have been an obvious matter to one of ordinary skill in the art to have altered the method of Obata, as by using a powder with the rare earths on the surface of a FeSi alloy as taught by Margaria, because Margaria teaches that the inventive inoculant provides a low sensitivity to the cast iron composition, and allows for good uniformity when a part with varying thicknesses is cast (see BRIEF SUMMARY), and further to have used a sandwich inoculant in the ladle known in the art because Olawale teaches that this technique delays reaction time and improves the efficiency of the process (see p. 406).
Regarding claim 2, Obata teaches that the rare earth can be La or Ce or a mischmetal (See col 3). Obata teaches that an alloy of La and Ce is added (Example 1).
Regarding claim 3, Obata teaches iron sulfide is added (see cols 3-4 and Example 1).
Regarding claim 4, Obata teaches in Example 1 that the alloys made contain 0.02% or 0.019% of rare earths, falling in the range as claimed and anticipating the whole range.
Regarding claim 5, No 2 of Obata includes 0.020% S (Example 1), falling in the range as claimed and establishing a prima facie case of obviousness for the range.
Regarding claim 9, Obata adds ferrosilicon and a recarburizer (Example 1). Obata adjusts the carbon to 3.75% and silicon to 2.00% in the melt (Example 1). The claimed amounts of C and Si fall in the ranges as claimed and anticipate the whole ranges.
Claim(s) 7-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Obata in view of Margaria and Olawale as applied to claim 1 above, further in view of US 20050103161 A1 (hereinafter “Horie”).
Regarding claim 7, Obata is applied as stated above. Obata does not tehc wherein a source of the iron is scrap or recycled scrap. Obata does not describe any source of the iron melt.
Horie teaches a method of reusing steel scrap for generation of spheroidal cast iron (See abstract or DISCLOSURE OF THE INVENTION). Horie teaches that the method uses scrap to make good quality of cast iron without cost increases (DISCLOSURE OF THE INVENTION).
It would have been an obvious matter to the skilled artisan at time of invention to have practiced the method of Obata, and to have sued scrap as taught by Horie, in order to make good quality of cast iron without cost increases as taught by Horie (DISCLOSURE OF THE INVENTION).
Regarding claim 8, it would have been an obvious matter to have used the scrap as taught by Horie, as stated above. Horie teaches that new metal (pig iron) is not added ([0011]). Because Horie does not teach adding new metal to the process, this would mean 100% scrap.
Claim(s) 10-11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Obata in view of Margaria and Olawale as applied to claim 1 above, further in view of Electric Arc Furnace Melting, ASM Handbook, vol 15, 2008, pp. 87-98 (Hereinafter “ASM Handbook”).
Regarding claim 10, Obata does not teach to add ferromanganese.
ASM Handbook teaches processes for electric arc furnace melting of ferrous materials (See p. 87). ASM Handbook teaches that in order to adjust the carbon composition of the metal, and to stop carbon boil, ferromanganese may be added to the melt (see The Refining Period on p. 94 and The oxidation, on p. 94). ASM Handbook teaches that final chemistry additions re made just before tapping (p. 97).
It would have been an obvious matter to one of ordinary skill in the art to have altered the method of Obata, as by adding ferromanganese to the iron, because ASM Handbook teaches that this controls the carbon content (see pp. 94 and 97).
Regarding the particle size of the ferromanganese, there is no size specified. However, the material is being added to the molten metal in order to control an overall chemistry (see ASM Handbook, p 94 and 97). Therefore the particle size of the added material is not believed to distinguish in any way, wherein the ferrosilicon is melted and distributed. Applicant is directed to MPEP 2144.04 IV.
Regarding the amount of manganese in the melt, the material is being added to the molten metal in order to control an overall chemistry (see ASM Handbook, p 94 and 97). ASM Handbook teaches that the ferromanganese is added in order to adjust the carbon composition of the metal (cited above0. This the amount of Mn is a results-effective variable with regard to the chemistry, and would have been optimized by the skilled artisan.
Response to Arguments
Applicant's arguments filed 14 January 2026 have been fully considered.
Applicant argues that the claims are not indefinite under 35 USC 112. No rejections are made under 35 USC 112 at this time.
Conclusion
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CHRISTOPHER S. KESSLER
Primary Examiner
Art Unit 1734
/CHRISTOPHER S KESSLER/ Examiner, Art Unit 1759
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