US3413166A - Fine grained steel and process for preparation thereof - Google Patents

Fine grained steel and process for preparation thereof Download PDF

Info

Publication number
US3413166A
US3413166A US496729A US49672965A US3413166A US 3413166 A US3413166 A US 3413166A US 496729 A US496729 A US 496729A US 49672965 A US49672965 A US 49672965A US 3413166 A US3413166 A US 3413166A
Authority
US
United States
Prior art keywords
steel
temperature
martensite
tempering
deformation
Prior art date
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
Application number
US496729A
Other languages
English (en)
Inventor
Victor F Zackay
Earl R Parker
Krahamadhati V Ravi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
US Atomic Energy Commission (AEC)
Original Assignee
Atomic Energy Commission Usa
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 Atomic Energy Commission Usa filed Critical Atomic Energy Commission Usa
Priority to US496729A priority Critical patent/US3413166A/en
Priority to GB42818/66A priority patent/GB1165728A/en
Priority to DE19661508453 priority patent/DE1508453A1/de
Priority to SE13906/66A priority patent/SE325591B/xx
Priority to FR80153A priority patent/FR1502127A/fr
Application granted granted Critical
Publication of US3413166A publication Critical patent/US3413166A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys

Definitions

  • This invention relates to alloy steels having high toughness, and more specifically to the production of a steel having a fine austenitic-martensitic micro-structure.
  • the invention described herein was made in the course of, or under, contract W7405eng48 with the United States Atomic Energy Commission.
  • An object of this invention is to provide steels having high tensile strength and ductility.
  • Another object of the invention is to provide a process for producing a high strength steel having a very fine grained austenitic-martensitic micro-structure.
  • M will refer to the temperature of the initial austenite to martensite transformation. Also M refers to the final austenite to martensite transformation temperature point at which all of the austenite is converted to martensite.
  • the process of this invention comprises the deforming of steel in an austenitic condition to form a heavy dislocation network, the deformation being followed by a cyclic heat treatment consisting of alternate heating at an elevated tempering temperature and cooling to progressively lower temperatures. At the lower temperatures a fine martensite micro-structure is formed.
  • a cyclic heat treatment consisting of alternate heating at an elevated tempering temperature and cooling to progressively lower temperatures.
  • a fine martensite micro-structure is formed.
  • the carbides precipitate on the heavy dislocation network formed by the initial deformation.
  • the martensite plates are fine in size because they are confined to the carbide dislocation grid matrix.
  • the first step in the process is the deformation of an austenitic steel at a temperature which is less than the tempering temperature.
  • the preferred deformation temperature is around 500 C., which is the temperature at which the dislocations are mobile and tend to segregate in an ordered array rather than a random dispersion. Because the number of dislocations is approximately proportional to the increase in strength of the cyclically treated steel, the percentage of deformation will likewise affect the increase in tensile strength. However, a minimum deformation of about 25% is required to form the heavy slip bands on which the carbides will precipitate. Less than 25% deformation will not give the high strength desired. The maximum deformation of the steel is about 90%.
  • the next step in the process after the warm working is the rapid quenching of the steel to a temperature slightly below the M point.
  • the M temperature was maintained well below room temperature, --30 C. to -40 C. in order to prevent inadvertent conversion to martensite.
  • the martensite plates so formed are small because they are trapped in the alloy carbide-dislocation grid. This effect is shown in the accompanying optical photomicrographs and will be hereinafter discussed in more detail.
  • the next step in the process is the tempering of the martensite formed in the first quench. Tempering of the martensite precipitates the carbides out of solution and forms carbides on the grain boundaries which limit the size of martensite formed in subsequent quench operations. Precipitation of the carbides lowers the initial M temperature and the steel is quenched again to a lower incremental value. The ideal incremental value was found to be 20 to 25 C. lower at each quench. However, this ideal differential varies with the composition of the steel. After each cyclic quench the steel is tempered. The steels were cyclically quenched down to liquid nitrogen temperature (196 C.) in less than ten cycles, depending on the increment used. Thus the process may be described as the cyclic quenching with intermediate tempering of an austenitic steel.
  • FIGURE 1 is an optical photomicrograph of 800x magnification for one type of steel.
  • the steel depicted in the picture is classified as Al, and has the composition shown in Table I.
  • FIGURE 1 there is shown an A-l steel which has been processed portion was used. Liquid nitrogen was added to the alcohol to reduce the temperature to successively lower incremental values.
  • An iron-constantan thermocouple was employed to measure the temperature of the cryogenic according to the following steps: 5 bath which was stirred frequently to minimize tempera- Ingots of induction melted Al steel approximately ture gradients. Close temperature control was assured by 2 /2" diam. and length, were cast in an inert atmosemploying a large amount of liquid and the use of fairly phere.
  • the bar was cut into short lengths and sealed in /z" diam. 109 mm. wall stainless steel tubing. The function of the tubing was to insure uniformity of temperature during the rolling operation.
  • the specimens were heated in a tube furnace prior to and during the rolling operation.
  • a preheat time of 15 minutes was used prior to the rolling operation in order to bring the stainless steel casing and the specimen up to the rolling temperature of 400 C.
  • the deformation process was carried out in steps of 25 mils per pass during the initial stages of deformation, and 15 mils per pass at the final stages of deformation.
  • the specimen was returned to the furnace for a period of approximately two minutes for reheating.
  • An infrared pyrometer sighted on the specimen during rolling was employed to insure that the specimen temperature remained relatively constant throughout the rolling operation.
  • the total time for 80% reduction in thickness of the specimen was less than one hour.
  • the specimen was water quenched to retain the 'austenite phase at room temperature.
  • the specimen was removed from the stainless steel jacket by cutting and samples were prepared for metallography.
  • the specimen was heated from room temperature to a pre-selected tempering temperature (cycle tempering temperature) followed by alternate quenching to decreasing cryogenic temperatures and intermediate tempering.
  • the heating medium for cycle tempering was a molten salt bath of nitrates in a resistance heated container. As shown in Table II tempering temperatures of 450 C., 500 C. and 600 C. were employed depending upon the steel composition. For the cryogenic quenching treatment a mixture of ethanol and liquid nitrogen in suitable pro- The tensile data for the Al steel process as described previously is shown in Table II, together with corresponding data for the other steels. Also shown in Table II is the tensile data for the Al steel which has not been given the 30 minute final tempering treatment. Without the final temper treatment the yield strength is 206.6K p.s.i., ultimate is 276.1K p.s.i. at 27% elongation.
  • FIGURE 1 The Al steel processed as described above without the final 30 minute temper is shown in FIGURE 1.
  • the steel was electrolytically polished and etched with 2% nital.
  • FIGURE 1 Upon close inspection of FIGURE 1, it can be seen that the carbides which have been precipitated out by the tempering treatment are uniformly distributed along the dislocation boundaries.
  • the low carbon content of the Al steel results in a microstructure having a large percentage of untransformed austenite as shown by the white areas.
  • the austenite is estimated to be 60% and the martensite is about 40% as shown by the dark areas.
  • the appearance of the tempered martensite in FIGURE 1 indicates a plate size of very fine proportions; less than 1.0 micron.
  • the cycle tempering temperature has a significant effect on the properties of the product.
  • Lower tempering temperatures are found to be suitable for optimum results with high carbon steel such as A-2, while higher tempering temperatures yield good results with low carbon alloys such as A-l.
  • the lower temperatures in the case of low carbon steels are not high enough to induce carbide precipitation while the high temperature above the optimum overages the carbides, leading to a fall in hardness and hence strength.
  • the high carbon alloy A-2 showed a drop in hardness at higher cycle tempering temperature of 625 C., this being due to excessive carbide agglomeration.
  • FIGURE 2 there is shown the effect of the cycle tempering temperature on the final hardness for the A2 steel. As can be seen for the 625 C.
  • cycle temper there is a catastrophic drop in the Rockwell C hardness after several cycle treatments. This indicates the optimum cycle tempering temperature is in the range of 400 C. However, for the low carbon A1 steel a higher cycle tempering temperature produces the optimum hardness as shown in FIGURE 3. In this case, a cycle tempering temperature of 625 C. gives the highest Rockwell C hardness. Thus it is seen that the cycle tempering affects the hardness of the steel due to carbide agglomeration.
  • the martensite plate size would be much higher as has been observed by examination of photomicrographs of an A-1 steel which has been austenitized at 1100 C. for 1 hour and, without deformation, direct quenched to liquid nitrogen temperature.
  • the steel is essentially 100 martensite and has a martensite plate length of greater than 3.0 microns, more than twice the plate lengths shown in Table III. It can be seen that a substantial amount of deformation is required in order to achieve the fine martensite plate size in the final product.
  • Process 4 the standard microstructure of an undeformed steel direct quenched forms essentially martensite.
  • the microstructure reveals the elongated martensite plates Which are typical when austenitic steel is direct quenched to below the M; temperature.
  • the steel is very brittle with low ductility.
  • the martensite plate size of the A-l steels from Processes 2, 3 and 4 is substantially greater than the steel in FIGURE 1.
  • the first process shown corresponds to the optical photomicrograph of FIGURE 1
  • Numbers and 6 correspond to the steel with no quenching and are essentially 100% austenite.
  • Step 5 indicates the effect on hardness by the process of 80% deformation, which essentially is a normal coldworking.
  • step (e) is a temperature in the range from about 400 to about 625 degrees centigrade and wherein the cyclic quenching of step (f) is terminated when said steel has a composition comprising about austenite and about 40% martensite.
  • a high strength alloy steel produced by the process of claim 1 comprised of fine grained tempered martensite in an austenitic matrix which has a metallurgical structure in which carbides are uniformly distributed along dislocation boundaries, the martensite having a plate size less than one micron across.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Articles (AREA)
  • Heat Treatment Of Steel (AREA)
US496729A 1965-10-15 1965-10-15 Fine grained steel and process for preparation thereof Expired - Lifetime US3413166A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US496729A US3413166A (en) 1965-10-15 1965-10-15 Fine grained steel and process for preparation thereof
GB42818/66A GB1165728A (en) 1965-10-15 1966-09-26 Fined Grained Steel and process for preparation thereof
DE19661508453 DE1508453A1 (de) 1965-10-15 1966-10-12 Verfahren zum Vergueten von Stahl hoher Festigkeit mit Austenit-Martensit Feingefuege
SE13906/66A SE325591B (de) 1965-10-15 1966-10-13
FR80153A FR1502127A (fr) 1965-10-15 1966-10-14 Acier à grains fins et son procédé d'obtention

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US496729A US3413166A (en) 1965-10-15 1965-10-15 Fine grained steel and process for preparation thereof

Publications (1)

Publication Number Publication Date
US3413166A true US3413166A (en) 1968-11-26

Family

ID=23973873

Family Applications (1)

Application Number Title Priority Date Filing Date
US496729A Expired - Lifetime US3413166A (en) 1965-10-15 1965-10-15 Fine grained steel and process for preparation thereof

Country Status (5)

Country Link
US (1) US3413166A (de)
DE (1) DE1508453A1 (de)
FR (1) FR1502127A (de)
GB (1) GB1165728A (de)
SE (1) SE325591B (de)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4358325A (en) * 1979-08-31 1982-11-09 General Motors Corporation Method of treating low carbon steel for improved formability
US4859164A (en) * 1986-12-06 1989-08-22 Nippon Piston Ring Co., Ltd. Ferrous sintered alloy vane and rotary compressor
US20080229893A1 (en) * 2007-03-23 2008-09-25 Dayton Progress Corporation Tools with a thermo-mechanically modified working region and methods of forming such tools
EP2090383A1 (de) * 2008-02-15 2009-08-19 Dayton Progress Corporation Verfahren zur thermomechanischen Verarbeitung von Werkzeugstahl und aus thermomechanischen Werkzeugstählen hergestellte Werkzeuge
US20090229417A1 (en) * 2007-03-23 2009-09-17 Dayton Progress Corporation Methods of thermo-mechanically processing tool steel and tools made from thermo-mechanically processed tool steels
US20100068549A1 (en) * 2006-06-29 2010-03-18 Tenaris Connections Ag Seamless precision steel tubes with improved isotropic toughness at low temperature for hydraulic cylinders and process for obtaining the same
US20100193085A1 (en) * 2007-04-17 2010-08-05 Alfonso Izquierdo Garcia Seamless steel pipe for use as vertical work-over sections
US20100319814A1 (en) * 2009-06-17 2010-12-23 Teresa Estela Perez Bainitic steels with boron
CN102644028A (zh) * 2011-02-18 2012-08-22 希德卡公司 具有优异韧性的高强度钢
US20120211132A1 (en) * 2011-02-18 2012-08-23 Siderca S.A.I.C. Ultra high strength steel having good toughness
US8821653B2 (en) 2011-02-07 2014-09-02 Dalmine S.P.A. Heavy wall steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US9187811B2 (en) 2013-03-11 2015-11-17 Tenaris Connections Limited Low-carbon chromium steel having reduced vanadium and high corrosion resistance, and methods of manufacturing
US9340847B2 (en) 2012-04-10 2016-05-17 Tenaris Connections Limited Methods of manufacturing steel tubes for drilling rods with improved mechanical properties, and rods made by the same
US9598746B2 (en) 2011-02-07 2017-03-21 Dalmine S.P.A. High strength steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US9644248B2 (en) 2013-04-08 2017-05-09 Dalmine S.P.A. Heavy wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
US9657365B2 (en) 2013-04-08 2017-05-23 Dalmine S.P.A. High strength medium wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
US9803256B2 (en) 2013-03-14 2017-10-31 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
US9970242B2 (en) 2013-01-11 2018-05-15 Tenaris Connections B.V. Galling resistant drill pipe tool joint and corresponding drill pipe
CN109762965A (zh) * 2019-02-01 2019-05-17 哈尔滨工业大学（威海） 一种超高强韧性Mn-B钢结构件连续在线制备方法
US10844669B2 (en) 2009-11-24 2020-11-24 Tenaris Connections B.V. Threaded joint sealed to internal and external pressures
US11105501B2 (en) 2013-06-25 2021-08-31 Tenaris Connections B.V. High-chromium heat-resistant steel
US11124852B2 (en) 2016-08-12 2021-09-21 Tenaris Coiled Tubes, Llc Method and system for manufacturing coiled tubing
CN113930591A (zh) * 2021-10-15 2022-01-14 常州大学 一种20Cr2Ni4A钢循环淬火细晶工艺
US11833561B2 (en) 2017-01-17 2023-12-05 Forum Us, Inc. Method of manufacturing a coiled tubing string
US11952648B2 (en) 2011-01-25 2024-04-09 Tenaris Coiled Tubes, Llc Method of forming and heat treating coiled tubing

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010062011B3 (de) 2010-11-26 2011-12-01 Leibniz-Institut Für Festkörper- Und Werkstoffforschung Dresden E.V. Verfahren zur Wärmebehandlung von hochfesten Eisenlegierungen

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2934463A (en) * 1959-04-17 1960-04-26 Ford Motor Co High strength steel
US3028270A (en) * 1958-08-25 1962-04-03 Yawata Iron & Steel Co Production of high tensile strength, high notch toughness steel by low temperature anneal
US3178324A (en) * 1963-06-03 1965-04-13 United States Steel Corp Method of producing ultrafine grained steel
US3189493A (en) * 1961-08-14 1965-06-15 Westinghouse Electric Corp Processes for producing ductile cobaltiron-vandium magnetic alloys
US3201288A (en) * 1963-11-01 1965-08-17 United States Steel Corp Method of treating steel to produce a fine-grained condition
US3250648A (en) * 1963-05-14 1966-05-10 United States Steel Corp Method of producing hardened steel products

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3028270A (en) * 1958-08-25 1962-04-03 Yawata Iron & Steel Co Production of high tensile strength, high notch toughness steel by low temperature anneal
US2934463A (en) * 1959-04-17 1960-04-26 Ford Motor Co High strength steel
US3189493A (en) * 1961-08-14 1965-06-15 Westinghouse Electric Corp Processes for producing ductile cobaltiron-vandium magnetic alloys
US3250648A (en) * 1963-05-14 1966-05-10 United States Steel Corp Method of producing hardened steel products
US3178324A (en) * 1963-06-03 1965-04-13 United States Steel Corp Method of producing ultrafine grained steel
US3201288A (en) * 1963-11-01 1965-08-17 United States Steel Corp Method of treating steel to produce a fine-grained condition

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4358325A (en) * 1979-08-31 1982-11-09 General Motors Corporation Method of treating low carbon steel for improved formability
US4859164A (en) * 1986-12-06 1989-08-22 Nippon Piston Ring Co., Ltd. Ferrous sintered alloy vane and rotary compressor
US4976916A (en) * 1986-12-06 1990-12-11 Nippon Piston Ring Co., Ltd. Method for producing ferrous sintered alloy product
US20100068549A1 (en) * 2006-06-29 2010-03-18 Tenaris Connections Ag Seamless precision steel tubes with improved isotropic toughness at low temperature for hydraulic cylinders and process for obtaining the same
US8926771B2 (en) 2006-06-29 2015-01-06 Tenaris Connections Limited Seamless precision steel tubes with improved isotropic toughness at low temperature for hydraulic cylinders and process for obtaining the same
US20080229893A1 (en) * 2007-03-23 2008-09-25 Dayton Progress Corporation Tools with a thermo-mechanically modified working region and methods of forming such tools
US8968495B2 (en) 2007-03-23 2015-03-03 Dayton Progress Corporation Methods of thermo-mechanically processing tool steel and tools made from thermo-mechanically processed tool steels
US20090229417A1 (en) * 2007-03-23 2009-09-17 Dayton Progress Corporation Methods of thermo-mechanically processing tool steel and tools made from thermo-mechanically processed tool steels
US9132567B2 (en) 2007-03-23 2015-09-15 Dayton Progress Corporation Tools with a thermo-mechanically modified working region and methods of forming such tools
US20100193085A1 (en) * 2007-04-17 2010-08-05 Alfonso Izquierdo Garcia Seamless steel pipe for use as vertical work-over sections
EP2090383A1 (de) * 2008-02-15 2009-08-19 Dayton Progress Corporation Verfahren zur thermomechanischen Verarbeitung von Werkzeugstahl und aus thermomechanischen Werkzeugstählen hergestellte Werkzeuge
US20100319814A1 (en) * 2009-06-17 2010-12-23 Teresa Estela Perez Bainitic steels with boron
US10844669B2 (en) 2009-11-24 2020-11-24 Tenaris Connections B.V. Threaded joint sealed to internal and external pressures
US11952648B2 (en) 2011-01-25 2024-04-09 Tenaris Coiled Tubes, Llc Method of forming and heat treating coiled tubing
US9598746B2 (en) 2011-02-07 2017-03-21 Dalmine S.P.A. High strength steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US8821653B2 (en) 2011-02-07 2014-09-02 Dalmine S.P.A. Heavy wall steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US9188252B2 (en) 2011-02-18 2015-11-17 Siderca S.A.I.C. Ultra high strength steel having good toughness
US8636856B2 (en) * 2011-02-18 2014-01-28 Siderca S.A.I.C. High strength steel having good toughness
US8414715B2 (en) * 2011-02-18 2013-04-09 Siderca S.A.I.C. Method of making ultra high strength steel having good toughness
CN102644028A (zh) * 2011-02-18 2012-08-22 希德卡公司 具有优异韧性的高强度钢
US9222156B2 (en) 2011-02-18 2015-12-29 Siderca S.A.I.C. High strength steel having good toughness
CN102644028B (zh) * 2011-02-18 2016-07-06 希德卡公司 具有优异韧性的高强度钢
US20120211131A1 (en) * 2011-02-18 2012-08-23 Siderca S.A.I.C. High strength steel having good toughness
US20120211132A1 (en) * 2011-02-18 2012-08-23 Siderca S.A.I.C. Ultra high strength steel having good toughness
US9340847B2 (en) 2012-04-10 2016-05-17 Tenaris Connections Limited Methods of manufacturing steel tubes for drilling rods with improved mechanical properties, and rods made by the same
US9970242B2 (en) 2013-01-11 2018-05-15 Tenaris Connections B.V. Galling resistant drill pipe tool joint and corresponding drill pipe
US9187811B2 (en) 2013-03-11 2015-11-17 Tenaris Connections Limited Low-carbon chromium steel having reduced vanadium and high corrosion resistance, and methods of manufacturing
US11377704B2 (en) 2013-03-14 2022-07-05 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
US10378075B2 (en) 2013-03-14 2019-08-13 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
US10378074B2 (en) 2013-03-14 2019-08-13 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
US9803256B2 (en) 2013-03-14 2017-10-31 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
US9644248B2 (en) 2013-04-08 2017-05-09 Dalmine S.P.A. Heavy wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
US9657365B2 (en) 2013-04-08 2017-05-23 Dalmine S.P.A. High strength medium wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
US11105501B2 (en) 2013-06-25 2021-08-31 Tenaris Connections B.V. High-chromium heat-resistant steel
US11124852B2 (en) 2016-08-12 2021-09-21 Tenaris Coiled Tubes, Llc Method and system for manufacturing coiled tubing
US11833561B2 (en) 2017-01-17 2023-12-05 Forum Us, Inc. Method of manufacturing a coiled tubing string
CN109762965A (zh) * 2019-02-01 2019-05-17 哈尔滨工业大学（威海） 一种超高强韧性Mn-B钢结构件连续在线制备方法
CN109762965B (zh) * 2019-02-01 2024-04-16 哈尔滨工业大学（威海） 一种超高强韧性Mn-B钢结构件连续在线制备方法
CN113930591A (zh) * 2021-10-15 2022-01-14 常州大学 一种20Cr2Ni4A钢循环淬火细晶工艺

Also Published As

Publication number Publication date
FR1502127A (fr) 1967-11-18
DE1508453A1 (de) 1969-10-23
GB1165728A (en) 1969-10-01
SE325591B (de) 1970-07-06

Similar Documents

Publication Publication Date Title
US3413166A (en) Fine grained steel and process for preparation thereof
US4021272A (en) Method of isothermal annealing of band steels for tools and razor blades
US4457789A (en) Process for annealing steels
US3907614A (en) Bainitic ferrous alloy and method
US4343661A (en) Method of making a low temperature bainite steel alloy gear
Kayali et al. The development of fine structure superplasticity in cast ultrahigh carbon steels through thermal cycling
Yuan et al. Effects of rapid heating on the phase transformation and grain refinement of a low-carbon mciroalloyed steel
CA1133287A (en) Lower bainite alloy steel article and method of making same
Johnson et al. Toughness of tempered upper and lower bainitic microstructures in a 4150 steel
US3889510A (en) Hot forging process
Wu et al. Effects of different annealing time on microstructure and mechanical properties of lightweight Al-containing medium-Mn steel
Sankaran et al. Microstructural evolution and tensile behaviour of medium carbon microalloyed steel processed through two thermomechanical routes
US3615925A (en) Heat-treatment of steels
Murphy et al. The Kinetics of Mo2C Precipitation in Tempered Martensite
JPH1025521A (ja) 線材の球状化焼鈍方法
JPH0310046A (ja) 微細粒ベイナイト鋼材
CA1151513A (en) Process for annealing steels
US3920490A (en) Thermally processed steel
US20220195551A1 (en) Unknown
Klueh et al. Heat-treatment effect on impact properties of reduced-activation steels
Ravi The Microstructure and Properties of Martensite Formed from Cyclically Transformed Austenite
JPS61279620A (ja) 鋼の加工熱処理法
SU834157A1 (ru) Способ термической обработки заготовок
RU2031963C1 (ru) Способ изготовления проката из углеродистых и легированных сталей с двухфазной структурой в виде мелкозернистого феррита и мелкодисперсного перлита
SU881133A1 (ru) Способ термической обработки заготовок из легированных конструкционных сталей