EP0033403A1 - Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone - Google Patents

Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone Download PDF

Info

Publication number
EP0033403A1
EP0033403A1 EP80300295A EP80300295A EP0033403A1 EP 0033403 A1 EP0033403 A1 EP 0033403A1 EP 80300295 A EP80300295 A EP 80300295A EP 80300295 A EP80300295 A EP 80300295A EP 0033403 A1 EP0033403 A1 EP 0033403A1
Authority
EP
European Patent Office
Prior art keywords
article
carbon
weight
surface region
region
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.)
Withdrawn
Application number
EP80300295A
Other languages
German (de)
English (en)
Inventor
Charles Arthur Stickels
Adam Mario Janotik
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.)
Ford Motor Co
Original Assignee
Ford Motor Co
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 Ford Motor Co filed Critical Ford Motor Co
Priority to EP80300295A priority Critical patent/EP0033403A1/fr
Publication of EP0033403A1 publication Critical patent/EP0033403A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/20—Carburising
    • C23C8/22—Carburising of ferrous surfaces
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/78—Combined heat-treatments not provided for above
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/80—After-treatment

Definitions

  • This invention relates to methods of treating the surfaces of high carbon steol bodies, and to bodies of high carbon steel.
  • Carburizing techniques are nearly always applied to low carbon, low alloy steels, such as AISI 8620, 4118 and 4620, which contain 0.1 - 0.3 wt. % of carbon.
  • low carbon, low alloy steels such as AISI 8620, 4118 and 4620, which contain 0.1 - 0.3 wt. % of carbon.
  • austenitized at temperatures too low to dissolve all carbides an effective equilibrium is established between undissolved carbide and the austenite, which is then saturated in carbon. It is also generally accepted that this saturation prevents such steel from accepting additional dissolved carbon, and thereby prevents an increase in the amount of carbon dissolved in the austenite near the surface. Therefore, an appreciation of carburization with respect to hypereutectoid alloy steels, has remained an unexplored area until this invention.
  • Steels used in ball and roller bearings are of the following types: (1) high carbon, low alloy steel, such as AISI 52100 (1% C, 1.5% Cr) through-hardened by heating to typically 825-850°C, quenching and tempering, (2) low carbon, low alloy steel such as AISI 8620, 4118 and 4620 hardened by carburizing the surface (to maximum surface carbon contents on the order of 1%), quenching and tempering, and (3) high carbon, high alloy steel such as N-50, a tool steel, or 440C, a stainless steel, used when elevated surface temperatures or other extreme operating conditions are anticipated.
  • high carbon, low alloy steel such as AISI 52100 (1% C, 1.5% Cr) through-hardened by heating to typically 825-850°C, quenching and tempering
  • low carbon, low alloy steel such as AISI 8620, 4118 and 4620 hardened by carburizing the surface (to maximum surface carbon contents on the order of 1%), quenching and tempering
  • high carbon, high alloy steel such as N-50,
  • Type (2) bearing steels as indicated above, have one distinct advantage in that substantial compressive residual stress can be developed at the part surface as a consequence of carburizing.
  • the favourable residual stress distribution is thought by the prior art to make a significant contribution to the durability of the bearing.
  • compressive residual stresses are not produced when steels of types (1) and (3) are hardened by the indicated conventional through-hardening techniques used by the prior art.
  • Carburizing has not been considered as a means of developing compressive surface residual stresses in types (1) and (3) bearing steels, since it has been generally accepted by the prior art that it is not possible to increase the surface dissolved carbon content by diffusing additional carbon into a hypereutectoid alloy steel from a furnace atmosphere at the usual austenitizing temperatures.
  • a method of treating a body of high carbon steel comprising the steps of heating the body in a carburizing atmosphere effective to generate a differential in retained austenite, primary carbides and carbon between the surface region and core region of the body article; and quenching the body at a rate sufficiently fast to effectively suppress the formation of non-martensitic austenite decomposition products, thereby establishing a residual compressive stress gradient proceeding from the surface region of the body to the core region thereof.
  • the invention also includes a high carbon steel alloy body having gradients of compressive residual stress, and at least one of a carbon gradient and hardness gradient proceeding from the surface region of said article to its core, said article being characterized by a microstructure consisting essentially of tempered martensive, retained austenite and a carbide phase, said article having a chemical content consisting essentially of 0.8 - 1.6% by weight of carbon, 0.75 - 25% by weight of alloying ingredients including 0.2 - 5% by weight of chromium, the remainder being essentially iron, said article having a compressive residual stress level at its surface region of at least 10,000 psi, and tensile stresses at the article core, said article having a hardness differential between its surface and core of at least 2.0 R c , and a volume fraction of primary carbides at its surface region of at least 0.18.
  • Preferred features of the method of' this invention comprise (a) using hypereutectoid alloy steels to contain 0.8 - 1.6 wt. pct. carbon and 1.0 -4.5 wt. pct. chromium, (b) increasing the austenitizing time during heat treatment to a period of about 1 hour, and (c) regulating the austenitizing furnace atmosphere to obtain a high carburizing potential typical of conventional gas carburizing (see Figure 12-2 of reference 4), said heat treatment atmosphere particularly being a gas blend of an endothermic gas and 3-10% methane.
  • the present invention provides for an economical and controllable method of increasing the fatigue life of a bearing by (a) providing compressive residual stresses in the surface of the steel specimen by a simple heat treatment in a carburizing atmosphere, (b) providing increased retained austenite in said surface zone, (c) providing an increased volume fraction of primary carbides near the surface, and (d) providing higher hardness near the surface, which is in part dependent on limiting and controlling the chromium content of the steel.
  • the heat treatment can be carried out at a relatively low temperature in a carbarizing atmosphere, and is best conducted for critical periods of time between 1 and 2 hours. The aim of this treatment is to establish a gradient normal to the surface of dissolved carbon in austenite.
  • the austenite in a plain carbon hypereutectoid steel a steel with negligible alloy content, heated to a temperature not high enough to dissove all of its iron carbides, rapidly becomes saturated in carbon. If carbon is supplied to the steel from the furnace atmosphere, the volume fraction of undissolved carbide (primary carbide) increases, but the amount of carbon dissolved in the austenite is unchanged.
  • a hypereutectoid steel containing an alloying element such as chromium, whose affinity for carbon is greater than the affinity or iron for carbon held at a temperature high enough to form austenite, but too low to dissolve all carbides, slowly redistributes its carbon and chromium between carbide and austenite phases.
  • Carburized high carbon alloy steels containing controlled chromium will contain a larger fraction of primary carbides near the surface than in the interior. Since the carbide phase exhibits no abrupt volume change on cooling (such as occurs when austenite forms martensite) and since the volume change can be a source of the residual stresses which develop, the higher carbide fraction at the surface should moderate any residual stresses which do develop.
  • Such an atmosphere is preferably derived by using an endothermic gas atmosphere, consisting primarily of CO, H 2 and N 22 generated by the partial combustion of a hydrocarbon.
  • the carbon potential can be adjusted by varying the proportions of air and hydrocarbon at the gas generator to match the carbon oontent of the part. But it is most important that such endothermic gas contain additional hydrocarbon, preferably by the addition of 3-10% methane.
  • the added hydrocarbon in the form of methane contributes the necessary carburizing capacity to the furnace atmosphere.
  • the oxygen content of the gas atmosphere should be reduced so that the formation of chromium oxide on the part surface will not interfere with carburizing. This may be obtained by controlling the gas atmosphere to contain nitrogen end methane in the proper proportions for achieving results equivalent to the results from an endothermic gas based carburizing atmosphere.
  • Vacuum carburizing is another method of carburizing without forming oxides.
  • the heated substrate or article is then subjected to cooling by ccnventional means, to produce the desired microstructure in the steel, usually martensite, such microstructure depending upon the application for the steel. Since the present invention is particularly suitable in those applications where rolling contact fatigue will be experienced, the microstructure should be hard and strong. In most instances, quenching in oil maintainea at a temperature of about 55°C provides a satisfactory cooling rate to achieve such strength and hardness. Slower quenches, e.g., into molten salt, or faster quenches, e.g., into water, may be used in some circumstances. Further cooling of the quenched steel by the use of liquid nitrogen to a temperature of -196°C will reduce the amount of retained austenite, usually producing a further increase in hardness and residual stress.
  • the article is immersed in a cooling medium to quench the central core of said article at a rate sufficiently fast to effectively suppress the formation of non-martensitic austenite decomposition products, thereby establishing a residual comprussive stress gradient proceeding from the surface region of said article to a depth of between 0.007 - 0.03 inches.
  • tempering cycle can be adjusted to suit a wide variety of needs; typically, heating to a temperature of 100-150°C and holding for approximately 1-2 hours is satisfactory.
  • the nominal composition of 52100 steel was 1.0% carbon, 1.5% chromium, 0.35% mangaanese, 0.25% silicon and the remainder substantially iron.
  • a total of 12 sample pieces were prepared according to the heat truat cycles indicated in Table 1; those having an asterisk were copper-plated to prevent carburization during heat treatment and were therefore subjected to a treatment equivalent to the prior art, which would not include carburization but rather just the heat treatment at the indicated temperatures in a neutral atmosphere.
  • the austenitizing heat treatments were carried out in a Lindberg carburizing furnace with an integral quench tank.
  • the gas atmosphere was generated as an endothermic gas atmosphere, enriched with methane.
  • a measure of the carburizing rate of the furnace atmosphere was obtained by determining the weight gain of a foil of 1008 steel, 0.064 mm thick, which was inserted through a sight port into the furnace, held at the temperature for 30 minutes, then rapidly cooled.
  • the gas mixture was adjusted prior to each of the runs so that the foil carbon content was at least 0.9 wt. pet. carbon.
  • foils were also included along with the samples when they were charged into the furnace, the initial carburizing rate was low.
  • the foil of Example 5 austenitized for only 30 minutes contained only 0.72 wt. pct. carbon; in every other case when the austenitizing times were longer, the foils accompanying the samples contained carbon in excess of the amount needed to saturate austenite.
  • the residual stress distribution in each sample was measured and hardness readings were taken.
  • the residual stress distribution is measured by progressively thinning the strips from one side only by chemical dissolution, measuring the bending of the strip and analyzing the deflection results using a modification of the method described by R. G. Treuting and W. T. Reed, Jr., Journaj of Applied Physics, Vol. 22, 1951, pp. 130-134.
  • Average hardness readings were taken for certain samples by a microhardness transverse (Knoop indentor 1 kgm load) through the surface region of the sanple.
  • Figure 1 shows that the plated specimen, which did not exchange carbon with the furnace atmosphere, developed a small surface tensile stress, while the unplated piece, which was carburized by the atmosphere, developed a surface compressive stress of about 15,000 psi at the surface, shown as a negative stress in Figure 1.
  • specimens tended to develop tensile suri'ece residual stresses; therefore, thu change (which is a sum of the tensile and compressive values) in residual stress distribution produced by carburizing is more substantial than the stress distribution in carburized pieces would suggest.
  • Example 3 The samples of Examples 3 and 4, which were austenitized at a slightly higher temperature and subjected to a liquid nitrogen quench following the oil quench, demonstrated a very slight compressive stress for the plated sample at the surface, whereas in the unplated sample, the compressive stress was approximately 7,000 psi at the surface.
  • the depth of compressive residual stress has been increased over that of Example 2, but the stress intensity is lowered due to the higher austenitizing temperature and the addition of the tempering treatment.
  • the averare microhardness of the outer surface region of Sample 7 to a depth of O.005" was determined to be 947 KHN (1kgm load, equivalent to 68-69 R c ).
  • the hardness decreased with increasing distance from the surface until the base hardness of 880 KHN (about 66-67 R ) was reached at a depth of 0.008 - 0.010".
  • This hardness gradient is an important aspect of the present invention and is attributed to the high carbon content of the martensite in the highrus surface region, as well as the greater volume fraction of carbides theraat, more than offsetting the greater volume fraction of retained austenite.
  • the Samples of Examples 10 to 12, Figure 5 show the effect of initial carbide size on the intensity of the residual stresses developed. Reducing the carbide size increases the rate of dissolution at 815°C. Sample 10 is the baseline for comparison. Pretreating Sample 11 at 980°C, followed by an air cool, to produce more finely divided carbides, has an adverse effect on the degree to which compressive surface stresses can be developed. Thus, Sample 12, with coarse, slowly dissolving primary carbides, can be treated to produce the highest residual stress.
  • KHM Average harunoss values
  • the retained austenite was measured by x-ray method on the carburized surface of Samples 11 and 12 and on their centre- lines after they had been thinned to measure residual stress. In both specimens, the average surface retained austenite was 24-26%. On the centreline of Sample 11, the average measurement was 15% retained austunite, and on the centreline of Sample 12, it was 9%. These differences in retained austenite are consistent with the expected differences in dissolved carbon. The differences are also consistent with the observation that quenching carburized specimens in liquid nitrogen to lower the retained austenite tends to increase the residual stresses.
  • Sample 16B was subjected to a different heat treat cycle wherein the material was heated in a carburizing atmosphere, to 1750°F (154°C) for 2 hours, air quenched, double tempered at 300°F (149°C) for 2 hours, and then air cooled.
  • Samples 14 and 16, like 13 each had significant compressive stress at the surface consistent with the control of chromium content and carburizing atmosphere.
  • the surface hardness of Sample 14 was not measurably greater than its interior hardness; the surface layer contained 14% retained austenite while the interior had 3% retained austenite.
  • specimen 16A showed a definite increase in surface hardness, there was no measurable difference between the amount of retained austenite at the surface and in the interior. All three factors - higher surface hardness, higher surface retained austenite and surface compressive residual stress - are important characteristics of an optimized carburized layer in these steels; however, either a hardness gradient or a gradient in retained austenite content may be absent in a carburized steel that is less than optimized, provided one or more of the other factors are present. A hardness gradient or retained austenite gradient need not always exist, even though carburization has occurred and residual surface compressive stresses develop.
  • Examples 1 to 12 show that by using a carburizing atmosphere for austenitizing treatments of about 1-2 hours at 815 to 850°C, with a 159°C temper, will produce compressive residual stresses to a depth of 0.2-0.4 mm below the surface with a maximum surface compressive stress in the order of 70-135 MPa (10-20 SKI).
  • the inventive method increases the amount of retained austenite and the volume fraction of primary carbides at the surface. The increase in surface retained austenite, particularly since the increase is accomplished without coarsening the austenite grains or reducing the hardness, is beneficial to increased contact fatigue life.
  • the depth of carburizing is quite shallow.
  • the depth of the compressive layer is about 0.016".
  • the amount of metal removed in finishing the bearing components of which these substrates may be employed, after heat treatment, must be within this thickness, and preferably no more than 0.002-0.004". This is necessary to maintain the benefit of the compressive stresses.
  • fatigue life is improved by the processing herein because of several factors; (a) residual compressive stresses at the surface, (b) more retained austenite at the surface, (c) a higher surface hardness, and (d) a larger volume fraction of carbides near the surface. All of these factors result from a carbon gradient normal to the surface, and the first two result from a gradient in dissolved carbon in austenite. Whether one of these factors, or all of them in combination, are responsible for the contact fatigue life improvement of this invention, is not known.
  • the Mn-Fe-C system for example, the first mechanism would not be expected to operate, because, according to R. Benz, J. F. Elliott and J. Chipman, Metallurgical Transactions, Vol. 4, 1973, pp. 1975-86, increasing the carbon content of the Mn-Fe-C system does not significantly increase the solubility of carbon in austenite for hypereutectoid steels.
  • the second mechanism would operate; thus, shallow surface compressive residual stresses of some magnitude could in theory be developed by short time austenitizing treatments in a carburizing atmosphere. In plain carbon hypereutectic steels, carbides dissolve so rapidly that neither mechanism could be expected to produce surface compressive residual stresses.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Heat Treatment Of Articles (AREA)
EP80300295A 1980-01-31 1980-01-31 Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone Withdrawn EP0033403A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP80300295A EP0033403A1 (fr) 1980-01-31 1980-01-31 Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP80300295A EP0033403A1 (fr) 1980-01-31 1980-01-31 Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone

Publications (1)

Publication Number Publication Date
EP0033403A1 true EP0033403A1 (fr) 1981-08-12

Family

ID=8187088

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80300295A Withdrawn EP0033403A1 (fr) 1980-01-31 1980-01-31 Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone

Country Status (1)

Country Link
EP (1) EP0033403A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993017146A1 (fr) * 1992-02-25 1993-09-02 Ina Wälzlager Schaeffler Kg Procede de traitement thermochimique-thermique d'aciers de cementation
NL1010795C2 (nl) * 1998-12-11 2000-06-19 Skf Eng & Res Centre Bv Slijtvast dimensioneel stabiel lageronderdeel voor toepassingen bij hoge temperatuur.
WO2005066383A1 (fr) 2003-12-22 2005-07-21 Caterpillar Inc. Procede de cementation d'un article en acier et article en acier ainsi obtenu presentant une resistance a l'usure amelioree
EP1847630A1 (fr) * 2005-02-08 2007-10-24 Parker Netsushori Kogyo K.K. ÉLÉMENT TREMPÉ DE FAIBLE CONTRAINTE/CARBURÉ DE FORTE CONCENTRATION ET PROCÉDÉ DE FABRICATION IDOINe
DE102006052834A1 (de) * 2006-11-09 2008-05-15 Schaeffler Kg Verfahren zum Herstellen eines Wälzlagerringes und Wälzlagerring
CN115558847A (zh) * 2022-09-22 2023-01-03 珠海格力电器股份有限公司 合金材料及其制备方法、滑片、压缩机和空调器
US11624106B2 (en) 2020-03-18 2023-04-11 Caterpillar Inc. Carburized steel component and carburization process

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1483040A1 (de) * 1964-06-24 1969-02-20 United States Steel Corp Verfahren zur Verguetung von Stahl
US4023988A (en) * 1976-02-02 1977-05-17 Ford Motor Company Heat treatment for ball bearing steel to improve resistance to rolling contact fatigue
DE2710748A1 (de) * 1976-03-11 1977-10-20 Airco Inc Verfahren zum karburieren von stahlteilen
AT347993B (de) * 1974-03-18 1979-01-25 Hawera Probst Kg Hartmetall Verfahren zum haerten von werkstuecken aus stahl und vorrichtung zur durchfuehrung des verfahrens

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1483040A1 (de) * 1964-06-24 1969-02-20 United States Steel Corp Verfahren zur Verguetung von Stahl
AT347993B (de) * 1974-03-18 1979-01-25 Hawera Probst Kg Hartmetall Verfahren zum haerten von werkstuecken aus stahl und vorrichtung zur durchfuehrung des verfahrens
US4023988A (en) * 1976-02-02 1977-05-17 Ford Motor Company Heat treatment for ball bearing steel to improve resistance to rolling contact fatigue
DE2710748A1 (de) * 1976-03-11 1977-10-20 Airco Inc Verfahren zum karburieren von stahlteilen

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993017146A1 (fr) * 1992-02-25 1993-09-02 Ina Wälzlager Schaeffler Kg Procede de traitement thermochimique-thermique d'aciers de cementation
NL1010795C2 (nl) * 1998-12-11 2000-06-19 Skf Eng & Res Centre Bv Slijtvast dimensioneel stabiel lageronderdeel voor toepassingen bij hoge temperatuur.
WO2000036164A1 (fr) * 1998-12-11 2000-06-22 Skf Engineering And Research Centre B.V. Composant de roulement a dimensions stables et resistant a l'usure pour applications a haute temperature
WO2005066383A1 (fr) 2003-12-22 2005-07-21 Caterpillar Inc. Procede de cementation d'un article en acier et article en acier ainsi obtenu presentant une resistance a l'usure amelioree
US7169238B2 (en) 2003-12-22 2007-01-30 Caterpillar Inc Carbide method and article for hard finishing resulting in improved wear resistance
EP1847630A1 (fr) * 2005-02-08 2007-10-24 Parker Netsushori Kogyo K.K. ÉLÉMENT TREMPÉ DE FAIBLE CONTRAINTE/CARBURÉ DE FORTE CONCENTRATION ET PROCÉDÉ DE FABRICATION IDOINe
EP1847630A4 (fr) * 2005-02-08 2011-01-12 Parker Netsushori Kogyo Kk ÉLÉMENT TREMPÉ DE FAIBLE CONTRAINTE/CARBURÉ DE FORTE CONCENTRATION ET PROCÉDÉ DE FABRICATION IDOINe
DE102006052834A1 (de) * 2006-11-09 2008-05-15 Schaeffler Kg Verfahren zum Herstellen eines Wälzlagerringes und Wälzlagerring
US11624106B2 (en) 2020-03-18 2023-04-11 Caterpillar Inc. Carburized steel component and carburization process
CN115558847A (zh) * 2022-09-22 2023-01-03 珠海格力电器股份有限公司 合金材料及其制备方法、滑片、压缩机和空调器

Similar Documents

Publication Publication Date Title
EP0013063B1 (fr) Procédé de traitement de surfaces de pièces d'acier à haute teneur en carbone
US5658082A (en) Rolling contact bearing and a method of producing thereof
Parrish Carburizing: microstructures and properties
US4930909A (en) Rolling bearing
US5503687A (en) Nitrogen enrichment of surface and near surface regions to produce a high-strength austenitic surface layer in stainless steels
US3860457A (en) A ductile iron and method of making it
US20050241734A1 (en) Rolling elements
EP1725693B1 (fr) Procede de cementation d'un article en acier presentant une resistance a l'usure amelioree
JP2005163173A (ja) 歯車部材およびその製造方法
EP0958397B1 (fr) Article d'acier presentant une durete elevee et une tenacite amelioree et procede permettant de former cet article
Qiang et al. Microstructure and tribological behaviour of nitrocarburizing-quenching duplex treated steel
Vilela Costa et al. Bending fatigue in low-pressure carbonitriding of steel alloys with boron and niobium additions
EP0033403A1 (fr) Procédé de traitement de la surface d'articles en acier à haute teneur en carbone et articles en acier à haute teneur en carbone
JP3792341B2 (ja) 冷間鍛造性及び耐ピッチング性に優れた軟窒化用鋼
Gerdemann et al. Microstructure and hardness of steel grade 9260 heat-treated by the quenching and partitioning (Q&P) process
Yang et al. Effects of carburization and hydrogenation on the impact toughness of AISI 4118 steel
JPS6224499B2 (fr)
Winter et al. Gas Nitriding and Gas Nitrocarburizing of Steels
Dossett Carbonitriding of steels
Grum Overview of residual stress after quenching. Part II: factors affecting quench residual stresses
Cohen et al. Assessment of bending fatigue limits for carburized steel
Steels Microstructure and properties
Anderson et al. Short-term hot-hardness characteristics of five case hardened steels
Burakowski et al. Comparison of sliding wear resistance of carburized and nitrided layers on 18HGT steel
JPH05179401A (ja) 軸受用鋼

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): IT SE

17P Request for examination filed

Effective date: 19810831

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19840224

RIN1 Information on inventor provided before grant (corrected)

Inventor name: STICKELS, CHARLES ARTHUR

Inventor name: JANOTIK, ADAM MARIO