US3132937A - Cast steel - Google Patents

Cast steel Download PDF

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Publication number
US3132937A
US3132937A US201328A US20132862A US3132937A US 3132937 A US3132937 A US 3132937A US 201328 A US201328 A US 201328A US 20132862 A US20132862 A US 20132862A US 3132937 A US3132937 A US 3132937A
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US
United States
Prior art keywords
cast
steel
cobalt
amounts
present
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US201328A
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English (en)
Inventor
Edward P Sadowski
Raymond F Decker
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Huntington Alloys Corp
Original Assignee
International Nickel Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Nickel Co Inc filed Critical International Nickel Co Inc
Priority to US201328A priority Critical patent/US3132937A/en
Priority to GB21934/63A priority patent/GB1033812A/en
Priority to ES288880A priority patent/ES288880A2/es
Priority to DK274063AA priority patent/DK103593C/da
Priority to AT463363A priority patent/AT264565B/de
Priority to LU43884D priority patent/LU43884A1/xx
Priority to CH726063A priority patent/CH452206A/fr
Application granted granted Critical
Publication of US3132937A publication Critical patent/US3132937A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
    • C22C38/105—Ferrous alloys, e.g. steel alloys containing cobalt containing Co and Ni
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium

Definitions

  • the present invention relates to ferrous-base alloys and, more particularly, to cast ferrous-base alloys containing nickel.
  • 839,296 are commercially available iron-base alloys containing, in percent by weight, about 18% to about 25% nickel, small interrelated amounts of carbon and columbium (niobium) and amounts of titanium and/or aluminum in the aggregate of at least about 1.5%.
  • These wrought Bieber alloys can be subjected to an age-hardening heat treatment while in the martensitic condition to provide hitherto unattainable combinations of strength and ductility at room temperature and lower.
  • the aforementioned Decker et al. U.S. application was concerned with wrought ferrous-base alloys containing about to about 27% nickel together with interrelated amounts of cobalt and molybdenum which could also be age hardened while in the martensitic condition.
  • Another object of the invention is to provide a novel ferrous-base alloy suitable for use as castings.
  • the invention also contemplates providing a novel cast, thermally-homogenized steel.
  • An additional object of the present invention is to provide a novel process for producing ultra-high strength castings.
  • the present invention contemplates a cast, hardenable steel having a martensitic matrix and containing, in percent by weight, about 14% or even about 16% to about 17.5% nickel, about 8% to about 12% cobalt, about 4% to about 5% molybdenum, up to about 0.45% titanium, e.g., about 0.1% to about 0.45% titanium, about 0.05% to about 0.45 aluminum, small unavoidable amounts of carbon not exceeding about 0.05 and up to about 0.1% zirconium with the balance being essentially iron.
  • the cast steel of the present in vention usually contains residual and effective trace amounts of elements usually employed in finishing and/ or deoxidation of maraging steel.
  • Such elements include silicon, manganese, boron, calcium, rare earth elements (from the addition of mischmetal), lithium, magnesium, uranium, etc. Effective amounts of these elements include amounts up to about 0.2% silicon and up to about 0.2% manganese.
  • the cast steel can also contain up to about 3.5% chromium with the chromium replacing nickel weight for weight and can contain small amounts of supplementary hardening elements such as tungsten, vanadium, columbium, tantalum, beryllium, copper, etc.
  • the amounts of such supplementary hardening elements which can be employed to increase the strength of the cast steels of the present invention are inversely related to the amounts of cobalt and molybdenum.
  • Acceptable miaximum amounts of supplementary hardeners used singly when the cobalt and molybdenum contents are both at the low end of the respective ranges are about 0.45% vanadium, about 2% tungsten, about 0.5 columbium, about 0.5% tantalum, about 3% copper and about 0.3% beryllium. When employed in combination, lesser maximum amounts of the supplementary hardeners must be employed. It is to be understood that the expression balance being essentially contemplates the inclusion in the alloys of residual, contaminant and/ or unavoidable amounts of impurities and/or incidental elements normally occurring in steel and/ or normally associated with the aforementioned alloying elements.
  • martensitic matrix refers to an alloy matrix which includes low temperature transformation products of austenite.
  • the steel of the present invention contains about 16.0% to about 17.5% nickel, about 9.5% to about 11.5% cobalt, about 4.4% to about 5.0% molybdenum, about 0.10% to about 0.45% titanium, about 0.05% to about 0.45% aluminum, up to about 0.03% carbon, up to about 0.1% zirconium, with the balance being essentially iron.
  • Impurities such as sulfur, phosphorus, nitrogen, oxygen, hydrogen, antimony, tin, selenium, tellurium, arsenic, and bismuth are advantageously kept at as low levels as commercially possible.
  • the cast steel of the present invention is produced by melting selected stock in air or under an inert atmosphere (including vacuum) in a melting furnace. Good results are obtained when electrolytic nickel, Armco iron, electrolytic cobalt and ferro-molybdenum are melted in a high frequency induction furnace using an argon blanket. After the charge is molten, silico-manganese is added followed by aluminum, titanium, boron, zirconium and calcium. Of course, if the carbon content of the initial charge is too high, such can be reduced by the use of oxygen. After all alloying and deoxidation and/or desulfurization additions have been made to the molten alloy, the metal is cast at temperatures of about 2700 F. to about 3000 F.
  • either direction i.e., from about 2050 F. to about 2150 F.
  • a protective atmosphere e.g., argon
  • the casting After the casting has been homogenized, it is cooled in air or more slowly to room temperature or at least to a temperature safely below the temperature required to transform the matrix thereof from austenite to martensite or a martensite-like phase.
  • the alloy After the alloy has been transformed by cooling, the alloy is age hardened by heating for about on to about ten hours at a temperature of about 800 F. to about 1000 F. and, advantageously, or about three hours at 900 F.
  • the age hardening heating is advantageously conducted in an oxidizing atmosphere, e.g., air, not only to induce strength characteristics in the alloy but also to provide a corrosion-resistant surface layer.
  • an oxidizing atmosphere e.g., air
  • protective coatings of substances such as nickel or cadmium can be used.
  • Iron includes small amounts of silicon, manganese and/or calcium in amounts within the ranges set forth hereinbelorc together with small amounts of impurities and incidental elements.
  • Cast steels within the present invention as set forth in Table I exhibit an advantageous combination of tensile characteristics such as yield strength (Y.S.) measured in thousands of pounds per square inch (K.S.I.), ultimate tensile strength (U.T.S.), Elongation (El.) measured in percent in one inch, reduction of area (R.A.) measured in percent and notch tensile strength (N .T.S.) together with good impact resistance as measured in foot pounds (ft. lbs.) in accordance with the Charpy V-Notch (C.V.N.) test conducted at room temperature.
  • Illustrative values of tensile and impact characteristics measured on cast alloy specimens which were homogenized at 2100 F. for four hours, air cooled to room temperature, then age hardened for three hours at 900 F. and air cooled are set forth in Table II.
  • Tables III and 1V show that while optimum characteristics are obtained when steels of the present invention are thermally homogenized at about 2100 F. for four hours, other homogenizing treatments conducted at temperatures from about 1800 F. to about 2200 F. for up to about eight or even up to about sixteen hours can be employed without excessive sacrifice of properties.
  • ferrous-base alloys or steels of the present invention as defined hereinbefore fall within a broad class of cobalt-containing steels which, in general, are highly useful as wrought and hardened structures.
  • cobalt-containing steels outside the present invention can exhibit low 'Charpy V-Notch impact values, e.g., below about 10 ft.-lbs., low percentages of elongation, e.g., below about 5%, and/ or low tensile and yield strengths, e.g., below about 230 K.S.I.U.T.S.
  • Iron includes small amounts of silicon, manganese, boron, zirconium and/or calcium together with small amounts of impurities and incidental elements.
  • the use of columbium, vanadium and/or copper in the alloys of the present invention detrimentally affects the toughness of the alloy.
  • Lowering the nickel content, the cobalt content and/ or the molybdenum content below the aforementioned specified ranges causes alloys of the present invention to lose strength whereas raising the cobalt and/ or molybdenum content above the specified ranges deleteriously affects the ductility of alloys of the present invention. Raising the nickel content above the specified range causes a loss of strength in the cast alloys of the present invention.
  • an increase in the amount of aluminum and/or titanium increases the strength of the alloy.
  • Cast steels of the present invention are particularly advantageous when compared to other wrought steel compositions employed in the cast condition.
  • a steel containing 18.5%, nickel, 7% cobalt, molybdenum, 0.4% titanum, 0.1% aluminum and 0.02% carbon together with small amounts of manganese, silicon, sulphur, phosphorus, boron, zirconium and calcium was cast, homogenized for four hours at 2100 F. and aged at 900 F. for three hours.
  • steels of this nominal composition exhibit low yield strengths and ultimate tensile strengths coupled with elongations below about 5%, reductions in area of about 12%, notch tensile strengths of the order of about 300 K81. and Charpy V-Notch values below about ft.-lbs.
  • the wrought steel composition when cast, exhibits a combination of mechanical characteristics including low ductility in combination with relatively low yield strength.
  • This combination of mechanical characteristics is substantially poorer than the combination of characteristics exhibited by similarly treated alloys of the present invention particularly suited for use as ultra high strength castings.
  • the cast steels and/ or ferrous-base alloys of the present invention are commercially advantageous in that they exhibit an outstanding combination of engineering characteristics when subjected to the relatively simple, quenchfree heat treatment disclosed hereinbefore.
  • the alloys of the present invention can be machined with ease to finish tolerances. Subsequent age hardening effects little dimensional change and does not induce severe strains and/or distortion in the finish-machined casting.
  • Other known ultra-high strength casting steels which require austenitizing, quenching and tempering heat treatments, are often difiicultly through-hardenable in large sections as compared to the readily through-hardenable steels of the present invention.
  • the known ultra-high strength cast alloys of Table VI After being austenitized (usually at a plurality of elevated temperatures), quenched and tempered in accordance with various recommendations of the originators and/ or producers thereof, the known ultra-high strength cast alloys of Table VI exhibit combinations of tensile and impact characteristics as set forth in Table VII in comparison with the average characteristics of the steel of the present invention homogenized for four hours at 2100 F. and age hardened after martensitic transformation at 900 F. for three hours.
  • Table VII shows that the far more readily heat treatable steel of the present invention exhibits, on the average, a yield strength comparable to those of the known ultra-high strength cast steels, enhanced ductility as indicated by percent elongation and percent reduction in area, enhanced impact resistance as indicated by the Charpy V-Notch results and enhanced resistance to stress, resistance to crack initiation and resistance to crack propagation, in the presence of notches as indicated by the ratio of the notch tensile strength to the ultimate tensile strength, said notch tensile strength being measured on a tensile specimen having the same notch characteristics as set forth hereinbefore in reference to Table II.
  • Cast steels of the present invention can be employed as dies, cast armor, high speed impellers, aircraft castings, hydrospin blanks, gun parts, parts for heavy road equipment, tools, forming equipment such as rolls, etc. Because of the unique combination of characteristics exhibited by the cast steels of the present invention, the steel can be employed as cast components in situations Where no other known cast steel can be employed. For example, by the use of the steels of the present invention, cast structures of heavy section can be produced having mechanical properties independent of the mass of the structure. The steels of the present invention can also be used in the wrought storm. For example, a steel of the present invention similar to steel N0. 11 which was hot rolled, annealed at 1500 F. for 1 hour and aged at 900 F.
  • the cast steel compositions of the present invention are to be distinguished from prior known steel composi tions which were particularly adapted to be employed in the wrought condition. It is well known that in many instances, casting provides a more economical and practical way to manufacture components of complicated design.
  • the alloys of the present invention provide the art with an ultra-high strength, cast material having substantially the advantages of the known wrought steels together with additional advantages as discussed hereinbefore making them particularly adaptable for use in casting processes.
  • An age-hardenable steel exhibiting particularly advantageous properties when employed as a thermally homogenized casting consisting essentially of, in percent by weight, about 14% to about 17.5% nickel, about 8% to about 12% cobalt, and 4% to about 5% molybdenum, up to about 0.45% titanium, about 0.05% to about 0.45 aluminum, up to about 0.05% carbon, up to about 0.1% zirconium, up to about 0.45 vanadium, up to about 2% tungsten, up to about 0.5% colum-bium, up to about 0.5% tantalum, up to about 3% copper, up to about 0.3% beryllium with the balance being essentially iron, the amounts of said elements in the group consisting of vanadium, tungsten, columbium, tantalum, copper and beryllium being inversely related to the amounts of cobalt and molybdenum and being maintained such that the maximum specified amounts are employed only when the cobalt and molybdenum contents of the steel are near the low end of the specified range and when only
  • a cast, thermally-homogenized age-hardenable steel consisting essentially of, in percent by weight, about 16% to about 17.5% nickel, about 9.5% to about 11.5% cobalt, about 4.4% to about 5.0% molybdenum, about 0.1% to about 0.45% titanium, about 0.05% to about 0.45% aluminum, carbon in unavoidable amounts up to about 0.03%, up to about 0.1% zirconium, with the balance being essentially iron.
  • a cast, thermally-homogenized steel consisting es sentially of, in percent by weight, about 16% to about 17.5% nickel, about 9.5% to about 11.5% cobalt, about 4.4% to about 5.0% molybdenum, about 0.1% to about 0.45% titanium, about 0.05% to about 0.45% aluminum, carbon in unavoidable amounts up to about 0.03%, up to about 0.1% zirconium, with the balance being essentially iron, said cast steel being characterized by a Charpy V-Notch impact strength of at least about 13 foot-pounds combined with a ratio of notched to unnotched tensile strength of at least about 1.3 when in a condition resulting from homogenizing at about 2100 F. and thereafter aging after transformation for about 1 to about 10 hours at about 800 F. to about 1000 F.
  • An age-hlardenable steel consisting essentially of in percent by Weight, about 16% to about 17.5% nickel, about 9.5% to about 11.5 cobalt, about 4.4% to about 5.0% molybdenum, about 0.1% to about 0.45 titanium, about 0.05% to about 0.45% aluminum, up to about 0.03% carbon, up to about 0.1% zirconium, with the balance being essentially iron.
  • a process for producing an ultra-high strength cast structure comprising pouring a molten mass of ferrousbase alloy consisting essentially of about 14% to about 17.5% nickel, about 8% to about 12% cobalt, about 4% to about 5% molybdenum, about 0.05% to about 0.45% aluminum, up to about 0.45% titanium and up to about 0.05% carbon into a mold, freezing said mass of ferrousbase alloy under grain-refining conditions to form a cast structure, thermally homogenizing said cast structure at a temperature of about 2050 F. to about 2150 F., transforming the thus homogenized cast structure to provide therein a martensitic matrix and thereafter aging the transformed cast structure at a temperature of about 800 F. to about 1000 F. for about 1 to about 10 hours to harden and strengthen said matrix.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
  • Conductive Materials (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
US201328A 1962-01-03 1962-06-11 Cast steel Expired - Lifetime US3132937A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US201328A US3132937A (en) 1962-06-11 1962-06-11 Cast steel
GB21934/63A GB1033812A (en) 1962-06-11 1963-05-31 Alloy steel
ES288880A ES288880A2 (es) 1962-06-11 1963-06-10 Mejoras introducidas en la fabricación de aceros al níquel-cobalto-molibdeno
DK274063AA DK103593C (da) 1962-06-11 1963-06-10 Stållegering og fremgangsmåde til varmebehandling heraf.
AT463363A AT264565B (de) 1962-06-11 1963-06-10 Nickel-Kobalt-Molybdän-Stahl und Verfahren zu seiner Wärmebehandlung
LU43884D LU43884A1 (de) 1962-06-11 1963-06-11
CH726063A CH452206A (fr) 1962-01-03 1963-06-11 Acier au nickel-cobalt-molybdène

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Application Number Priority Date Filing Date Title
US201328A US3132937A (en) 1962-06-11 1962-06-11 Cast steel

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US3132937A true US3132937A (en) 1964-05-12

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US (1) US3132937A (de)
AT (1) AT264565B (de)
DK (1) DK103593C (de)
ES (1) ES288880A2 (de)
GB (1) GB1033812A (de)
LU (1) LU43884A1 (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3313662A (en) * 1964-08-20 1967-04-11 Allegheny Ludlum Steel Maraging steel
US3341372A (en) * 1965-07-12 1967-09-12 Int Nickel Co Process for heat treating cast maraging steels
US3369892A (en) * 1965-08-20 1968-02-20 Chromalloy American Corp Heat-treatable nickel-containing refractory carbide tool steel
US3378913A (en) * 1964-03-25 1968-04-23 Caterpillar Tractor Co Friction welding maraging steel
US3396013A (en) * 1966-03-21 1968-08-06 Int Nickel Co Beryllium-containing maraging steel
US3650845A (en) * 1968-03-28 1972-03-21 Mitsubishi Heavy Ind Ltd Method of manufacture of steel turbine blades
US4013458A (en) * 1974-06-17 1977-03-22 The International Nickel Company, Inc. Cast maraging steel
FR2637615A1 (fr) * 1988-10-11 1990-04-13 Rauma Repola Oy Acier maraging et procede pour le preparer
US20060081309A1 (en) * 2003-04-08 2006-04-20 Gainsmart Group Limited Ultra-high strength weathering steel and method for making same
US20100037992A1 (en) * 2006-08-03 2010-02-18 Gay Gerald Method for transforming steel blanks
US20100047108A1 (en) * 2006-08-03 2010-02-25 Gay Gerald Process for manufacturing steel blanks
CN106282760A (zh) * 2016-10-18 2017-01-04 河池学院 一种关节机器人的旋转轴材料
US20170342517A1 (en) * 2015-02-25 2017-11-30 Hitachi Metals, Ltd. Hot-working tool and manufacturing method therefor
US20240367248A1 (en) * 2021-08-16 2024-11-07 Ab Sandvik Coromant Method of making a tool
US12617034B2 (en) * 2021-08-16 2026-05-05 Ab Sandvik Coromant Method of making a tool

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108754338B (zh) * 2018-05-11 2020-08-28 敬业钢铁有限公司 一种高磁感低铁损取向硅钢的生产工艺

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB427593A (en) * 1933-06-29 1935-04-26 Krupp Ag Improvements in iron alloys
US2102238A (en) * 1931-10-01 1937-12-14 Int Nickel Co Copper-nickel-titanium alloys

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2102238A (en) * 1931-10-01 1937-12-14 Int Nickel Co Copper-nickel-titanium alloys
GB427593A (en) * 1933-06-29 1935-04-26 Krupp Ag Improvements in iron alloys

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3378913A (en) * 1964-03-25 1968-04-23 Caterpillar Tractor Co Friction welding maraging steel
US3313662A (en) * 1964-08-20 1967-04-11 Allegheny Ludlum Steel Maraging steel
US3341372A (en) * 1965-07-12 1967-09-12 Int Nickel Co Process for heat treating cast maraging steels
US3369892A (en) * 1965-08-20 1968-02-20 Chromalloy American Corp Heat-treatable nickel-containing refractory carbide tool steel
US3369891A (en) * 1965-08-20 1968-02-20 Chromalloy American Corp Heat-treatable nickel-containing refractory carbide tool steel
US3396013A (en) * 1966-03-21 1968-08-06 Int Nickel Co Beryllium-containing maraging steel
US3650845A (en) * 1968-03-28 1972-03-21 Mitsubishi Heavy Ind Ltd Method of manufacture of steel turbine blades
US4013458A (en) * 1974-06-17 1977-03-22 The International Nickel Company, Inc. Cast maraging steel
GB2223763B (en) * 1988-10-11 1993-04-07 Rauma Repola Oy Maraging steel
GB2223763A (en) * 1988-10-11 1990-04-18 Rauma Repola Oy Maraging steel
FR2637615A1 (fr) * 1988-10-11 1990-04-13 Rauma Repola Oy Acier maraging et procede pour le preparer
US20060081309A1 (en) * 2003-04-08 2006-04-20 Gainsmart Group Limited Ultra-high strength weathering steel and method for making same
US8252129B2 (en) 2006-08-03 2012-08-28 Aubert & Duval Method for transforming steel blanks
US20100047108A1 (en) * 2006-08-03 2010-02-25 Gay Gerald Process for manufacturing steel blanks
US8101004B2 (en) * 2006-08-03 2012-01-24 Aubert & Duval Process for manufacturing steel blanks
US20100037992A1 (en) * 2006-08-03 2010-02-18 Gay Gerald Method for transforming steel blanks
US8551397B2 (en) 2006-08-03 2013-10-08 Aubert & Duval Process for manufacturing steel blanks
US20170342517A1 (en) * 2015-02-25 2017-11-30 Hitachi Metals, Ltd. Hot-working tool and manufacturing method therefor
US10494688B2 (en) * 2015-02-25 2019-12-03 Hitachi Metals, Ltd. Hot-working tool and manufacturing method therefor
CN106282760A (zh) * 2016-10-18 2017-01-04 河池学院 一种关节机器人的旋转轴材料
US20240367248A1 (en) * 2021-08-16 2024-11-07 Ab Sandvik Coromant Method of making a tool
US12617034B2 (en) * 2021-08-16 2026-05-05 Ab Sandvik Coromant Method of making a tool

Also Published As

Publication number Publication date
GB1033812A (en) 1966-06-22
AT264565B (de) 1968-09-10
ES288880A2 (es) 1963-12-01
DK103593C (da) 1966-01-24
LU43884A1 (de) 1963-09-04

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