CN105814230B - The method for manufacturing ferrous metal part - Google Patents

The method for manufacturing ferrous metal part Download PDF

Info

Publication number
CN105814230B
CN105814230B CN201480067722.7A CN201480067722A CN105814230B CN 105814230 B CN105814230 B CN 105814230B CN 201480067722 A CN201480067722 A CN 201480067722A CN 105814230 B CN105814230 B CN 105814230B
Authority
CN
China
Prior art keywords
axis
test block
desiliconization
demanganize
grain boundary
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 - Fee Related
Application number
CN201480067722.7A
Other languages
Chinese (zh)
Other versions
CN105814230A (en
Inventor
平松真
平松真一
稻垣功二
金泽孝明
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.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
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 Toyota Motor Corp filed Critical Toyota Motor Corp
Publication of CN105814230A publication Critical patent/CN105814230A/en
Application granted granted Critical
Publication of CN105814230B publication Critical patent/CN105814230B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C8/00Solid 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
    • C23C8/06Solid 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
    • C23C8/08Solid 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
    • C23C8/20Carburising
    • C23C8/22Carburising of ferrous surfaces
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06Surface hardening
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/773Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material under reduced pressure or vacuum
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D3/00Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02Extraction of non-metals
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0068Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C8/00Solid 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
    • C23C8/02Pretreatment of the material to be coated

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)

Abstract

A kind of method for manufacturing ferrous metal part, including:Element removal processing is performed to the workpiece formed by ferrous material;And after element removal processing, Surface hardening treatment is performed to workpiece by Carburization Treatment.In the method, element removal processing is performed under conditions of compared with Carburization Treatment higher temperature and lower pressure.

Description

The method for manufacturing ferrous metal part
Technical field
The present invention relates to a kind of method for making metallic hardfacing manufacture ferrous metal part using Carburization Treatment, and especially It is related to a kind of technology of brittleness oxydic layer of grain boundary for suitably reducing during Carburization Treatment and being formed on metal surface.
Background technology
For example, in the ferrous metal part for making such as steel part as main component comprising Fe, it is known that one kind is for example, by gas Carbon is embedded in metal surface and then the technology by quenching the hardness to enhance metal surface by Carburization Treatment.For example, Japan is specially Profit application discloses 05-171348 (JP 05-171348 A) number and discloses this ferrous metal part.
However, in JP 05-171348 A, it is known that the oxygen included in carburizing gas during gas carburizing processing Penetrate into ferrous metal part material surface crystal boundary and by with material surface included in such as Si, Mn or Cr element knot Conjunction forms brittleness oxydic layer of grain boundary.In order to handle it, in JP 05-171348 A, wrapped by reducing in ferrous metal part The content of Si, Mn or Cr for containing reduce the formation of oxydic layer of grain boundary.
Invention content
Ferrous metal part disclosed in JP 05-171348 A has the office of the content for the element for reducing such as Si, Mn or Cr It is sex-limited, thus its problem is the crystal boundary oxygen that the element of such as Si, Mn or Cr that the surface because of ferrous metal part is included are formed Change layer and make the decrease of fatigue strength of ferrous metal part.
The present invention provides a kind of methods for manufacturing ferrous metal part, and this method can be by suitably reducing in Carburization Treatment The oxydic layer of grain boundary that period is formed improves fatigue strength.
Due to various analyses and investigation, inventor has discovered that following facts.That is, find the member of such as Si, Mn or Cr Element evaporation, that is, the surface for the workpiece that ferrous material is formed under conditions of compared with Carburization Treatment higher temperature and lower pressure Element removal phenomenon has occurred.Moreover, usually element removal phenomenon has such as the negative impression in the case of " decarburization ".However, On the contrary, it finds by being sent out based on the technological know-how in relation to carburizing the element to be made to remove phenomenon before carrying out Carburization Treatment It is raw, it can suitably inhibit the formation of oxydic layer of grain boundary in subsequent Carburization Treatment.The present invention have been based on above-mentioned discovery and It makes.
A kind of method of manufacture ferrous metal part of scheme according to the present invention includes:The workpiece formed to ferrous material is held Row element removal is handled;And after element removal processing, Surface hardening treatment is performed to workpiece by Carburization Treatment.At this In method, element removal processing is performed under conditions of compared with Carburization Treatment higher temperature and lower pressure.
In the method according to the manufacture ferrous metal part of the program, element removal processing is compared with Carburization Treatment higher temperature And performed under conditions of lower pressure.Therefore, before Carburization Treatment, the member of oxide formation is caused during Carburization Treatment Element is by the surface evaporation from workpiece.It therefore, can be by the oxydic layer of grain boundary formed on the surface of workpiece during Carburization Treatment It suitably removes, and the fatigue strength of ferrous metal part can improve.
According to the program, in element removal processing, before Carburization Treatment, on workpiece surface during Carburization Treatment The element for forming oxide can be by the surface evaporation from workpiece.Therefore, it is formed during Carburization Treatment on the surface of workpiece Oxydic layer of grain boundary can be properly removed.
According to the program, in element removal processing, element can be in a vacuum by the surface evaporation from workpiece.Therefore, It can be properly removed in the oxydic layer of grain boundary formed on the surface of workpiece during Carburization Treatment.
According to the program, element can be at least one of Mn, Si and Cr.Therefore, in element removal processing, have At least one of Mn, Si and Cr of relatively high steam pressure are by the surface evaporation from workpiece.Therefore, during Carburization Treatment It can be properly removed in the oxydic layer of grain boundary formed on the surface of workpiece.
According to the program, after element removal processing, the higher temperature of element removal processing can be down to Carburization Treatment Temperature to perform Carburization Treatment.Therefore, after element removal processing, Carburization Treatment can be persistently appropriately performed.
Description of the drawings
It is important to describe the feature of exemplary embodiment of the present invention, advantage and technology and industry below with reference to accompanying drawings Property, wherein, identical label represents identical element, and wherein:
Fig. 1 is to show to be used for using the axis and showing manufactured by the method for manufacture ferrous metal part according to the present invention Manufacture the schematic diagram of the configuration of the device of the axis;
Fig. 2 is the flow chart of the manufacturing process for the axis for showing Fig. 1;
Fig. 3 is to show desiliconization demanganize process shown in Fig. 2 and temperature condition and pressure strip in Gas Carburizing Process The schematic diagram of part;
Fig. 4 is to show experiment I as a result, the survey formed in experiment I by using the material identical with the axis of Fig. 1 Test specimen, in different temperature (DEG C), pressure (Pa) and under conditions of the retention time (min) during the desiliconization demanganize of Fig. 2 Measure the content (mass percent) of Si, Mn and Cr included in the surface of test block;
Fig. 5 is to show Mn and Si that the surface of the test block formed by the material identical with the axis of Fig. 1 is included The schematic diagram of content, the test block include the test block (root manufactured by the desiliconization demanganize process and Gas Carburizing Process of Fig. 2 According to the axis of example 1) and the test block that is only manufactured by the Gas Carburizing Process of Fig. 2 (according to the axis of comparative example 1);
Fig. 6 is shown in the test block (according to the axis of example 1) and test block (according to the axis of comparative example 1) of Fig. 5 The schematic diagram of the thickness of the oxydic layer of grain boundary of formation;
Fig. 7 is the schematic diagram of the part surface for the test block (according to the axis of comparative example 1) for showing Fig. 5;
Fig. 8 is the schematic diagram of the part surface for the test block (according to the axis of example 1) for showing Fig. 5;
Fig. 9 be show Fig. 5 test block (according to the axis of example 1) and test block (according to the axis of comparative example 1) it is tired The schematic diagram of labor intensity;And
Figure 10 is schematic diagram corresponding with Fig. 1, and it illustrates the manufacturers according to another exemplary ferrous metal part of the present invention Method.
Specific embodiment
The example 1 of the present invention is described below in reference to attached drawing.In the attached drawing of example 1 below, suitably simplify and change Into per part, its size, shape etc. may not be illustrated accurately.
Fig. 1 is to show the schematic diagram of ferrous metal part that the present invention is suitably applied to, i.e., for example including making in the car Axis 10 in variable v-belt drive (CVT).Axis 10 is formed by making ferrous material as main component comprising Fe, example Such as, it is formed by the steel of C content such as with 0.02% to 2.14% (wt%) or the mild steel of case-hardened steel.The table of axis 10 Face carries out carburizing by the gas carburizing system 12 of Fig. 1;Therefore make the Surface hardened layer.
Gas carburizing system 12 will be described herein.As shown in Figure 1, gas carburizing system 12 includes:Thermal processing chamber 16, It is formed by heat insulator 14 and accommodates axis 10;Fixture 18, the fixed and support shaft 10 in thermal processing chamber 16;Heater 20, heat the inside of thermal processing chamber 16;Mass flow controller 24 measures and the supply from supply such as nitrogen is controlled to set Standby 22 are flowed into the flow of the nitrogen in thermal processing chamber 16;And drawdown pump 26, to the internal air exhausting of thermal processing chamber 16 To reduce the internal pressure of thermal processing chamber 16.Therefore, in gas carburizing system 12, axis 10 can be in thermal processing chamber 16 Relatively-high temperature and relatively low pressure are maintained at by heater 20 included in gas carburizing system 12 and drawdown pump 26 Under the conditions of.In addition, the temperature of axis 10 is cooled down by being used as the nitrogen of the cooling gas supplied from supply arrangement 22, so as to cool down Axis 10.In addition, gas carburizing system 12 is equipped with carburizing gas supply arrangement (not shown), which will ooze Carbon gas is supplied to thermal processing chamber 16.During gas carburizing processing, it is continually provided and oozes from carburizing gas supply arrangement Carbon gas.Carburizing gas for example, by will the source gas body such as propane flammable gas, town gas, natural gas or wood gas and air with pre- Fixed ratio mixes and is heated to decomposing to prepare by the mixed gas.
In addition, will the method that axis 10 is manufactured according to example 1, i.e. manufacturing process P1 to P5 be described using Fig. 2 herein.
As shown in Fig. 2, first, it, will be for example as case-hardened steel for example, by forging in forging process P1 The component shaping that the ferrous material (Steel material) of SCR420 is formed is predetermined shape.
Then, in (annealing) process P2 is preheated, the workpiece formed in forging process P1 is annealed and is softened.
Then, in mechanical processing process P3, the workpiece softened in warm P2 is cut by being machined The shape identical with axis 10.
Then, in desiliconization demanganize (element removal) process P4, as the workpiece cut in mechanical processing process P3 Axis 10 be arranged in gas carburizing system 12 and be maintained at than Gas Carburizing Process described below (carburizing process) P5 temperature Higher and pressure it is lower under conditions of continue scheduled time t (min), for example, in the internal temperature T (DEG C) of thermal processing chamber 16 For 1000 DEG C to 1300 DEG C and vacuum, i.e. the internal pressure P (Pa) of thermal processing chamber 16 is the condition of 100Pa to 1000Pa Under, the scheduled time t is, for example, 5 minutes to 30 minutes.Therefore, evaporated such as Mn included in the surface of axis 10, The element with relatively high steam pressure of Si or Cr.In desiliconization demanganize process P4, vacuum is represented compared with atmospheric pressure Sufficiently low pressure, for example, about 100Pa are to 1000Pa.The pressure P (100Pa to 1000Pa) of desiliconization demanganize process P4 is compared with for example It is sufficiently low for the pressure condition (higher than 1KPa and below 10KPa) of the vacuum carburization processing of the prior art.
Then, in Gas Carburizing Process P5, by a temperature of about 930 DEG C of gas carburizing as shown in Figure 3 Carburizing gas, carbon is embedded in the surface of axis 10, the axis 10 with such as Mn, Si or Cr element in desiliconization demanganize process From the surface of its evaporation in P4.Then, carburizing axis 10 is hastily cooled down and is quenched.Therefore, the surface by being hardened is produced And improve the axis 10 of fatigue strength.In gas carburizing system 12, as shown in figure 3, after desiliconization demanganize process P4, temperature Such as about 930 DEG C of gas carburizing temperature is down to perform Gas Carburizing Process P5.In addition, in the inside of thermal processing chamber 16 Pressure is about 1.0 × 105Pa performs Gas Carburizing Process P5 under atmospheric pressure that is, shown in Fig. 3.
Other than the mechanism of carburizing and quenching is carried out to axis 10, gas carburizing system 12 further includes makes heat before carburization The inside of processing chamber housing 16 is maintained at the mechanism under high temperature and low pressure (vacuum).Therefore, the manufacturing process P1 of example 1 is being performed extremely During P5, i.e., when performing desiliconization demanganize process P4 and Gas Carburizing Process P5, in addition to the prior art carries out carburizing to axis 10 Except the gas carburizing system of quenching, it is not necessary that for example in desiliconization demanganize process P4 addition make axis 10 be maintained at high temperature and New equipment under low-pressure state.Therefore, manufacture cost can be significantly reduced.
[experiment I]
The experiment I for the present inventor will be described being carried out herein.Carry out experiment I with prove the Si of the surface evaporation from axis 10, The fact that amount of Mn and Cr can suitably increase, that is, can be by changing temperature T (DEG C), pressure in desiliconization demanganize process P4 Power P (Pa) and retention time t (min) suitably reduces the content of Si, Mn and Cr included in the surface of axis 10.
In I is tested, under the conditions of 16 kinds, i.e., in condition 1 to 16 times execution desiliconization demanganize process P4 of condition, wherein:It adopts With by the material identical with axis 10, i.e. SCR420 is formed and is had the test block of predetermined shape (for example, Ф 18mm × 50mm);Temperature Degree T (DEG C) change in the range of 1000 DEG C to 1300 DEG C as shown in Figure 4, i.e. temperature T (DEG C) for 1000 DEG C, 1100 DEG C, 1200 DEG C or 1300 DEG C;Pressure P (Pa) changes in the range of 100Pa to 1000Pa, i.e. pressure P (Pa) for 100Pa, 200Pa, 500Pa or 1000Pa;And retention time t (min) changed in the range of 5 minutes to 30 minutes, i.e. retention time t (min) is 5 Minute, 10 minutes, 15 minutes or 30 minutes.Measure corresponding to axis 10 test block on it under condition 1 to condition 16 Perform the content of Si, Mn and Cr in the surface of desiliconization demanganize process P4.
In I is tested, as shown in figure 5, the per unit mass of the depth on 6 μm of the surface away from the test block corresponding to axis 10 10 times of Si contents (mass percent), Mn contents (mass percent) and Cr contents (mass percent) and (10Si+Mn + Cr) it is represented by the content y (mass percent) of Si, Mn and Cr in the surface for the test block for corresponding to axis 10.In addition, away from right Aura should be passed through in the content (mass percent) of Si, Mn and Cr of the per unit mass of the depth on 6 μm of the surface of test block Emission spectrum discharge to measure.
Fig. 4 be will hereinafter use to describe the result of experiment I.As shown in figure 4, the content y (matter of Si, Mn and Cr of test block Measure percentage) condition 8, condition 9 and condition 13 time be relatively small 2 (mass percents) below.It is therefore contemplated that pass through In condition 8, condition 9 and the execution desiliconization demanganize process P4 of condition 13 times, can suitably reduce the Si included in the surface of axis 10, The content y (mass percent) of Mn and Cr.
In addition, the experimental result by using condition 1 shown in Fig. 4 to condition 16 carries out multiple regression analysis, obtain Temperature T (DEG C), pressure P (Pa) and retention time t (min) in desiliconization demanganize process P4 and the test block corresponding to axis 10 Relational expression (1) between the content y (mass percent) of Si, Mn and Cr in surface.Y (mass percent)=- 0.0018×T(℃)+0.0001×P(Pa)-0.0242×t(min)+6.47677…(1)
From relational expression (1) as can be seen that in desiliconization demanganize process P4, suitably made by increasing temperature T (DEG C) The element of such as Si, Mn or Cr suitably make such as Si, Mn or Cr from the surface evaporation of axis 10 by reducing pressure P (Pa) Element from the surface evaporation of axis 10, and by increase retention time t (min) suitably make the element of such as Si, Mn or Cr from The surface evaporation of axis 10.In general, when the content y (mass percent) of Si, Mn and Cr in the surface of axis 10 are 2 (quality percentages Than) below when, the thickness of oxydic layer of grain boundary A (with reference to Fig. 7) formed on the surface by Carburization Treatment can be suppressed in 6.0 μm hereinafter, can thus inhibit the decline of fatigue strength.It is therefore contemplated that for example by setting the temperature in desiliconization demanganize process P4 T (DEG C), pressure P (Pa) and retention time t (min) make the content y (mass percent) of Si, Mn and Cr in the surface of axis 10 be 2 (mass percents) are hereinafter, can suitably inhibit in Gas Carburizing Process P5 in the crystal boundary oxygen formed on the surface of axis 10 Change layer A.
[experiment II]
To the experiment II that carried out by the present inventor be described herein.Experiment II is carried out to prove the manufacturing process P1 to P5 of Fig. 2 Influences of the middle desiliconization demanganize process P4 to axis, i.e. desiliconization demanganize process P4 is to the oxydic layer of grain boundary A's that is formed on the surface of axis 10 It influences.In II is tested, the influence of the oxydic layer of grain boundary A that is formed on axis 10 to the fatigue strength of axis 10 is also demonstrated.
It in II is tested, measures and is formed by the material identical with axis 10, i.e., formed by SCR420 and there is preboarding The thickness (μm) of oxydic layer of grain boundary A formed on the test block of shape (for example, Ф 18mm × 50mm), the test block include:With root According to the 10 corresponding test block of axis (desiliconization demanganize+gas carburizing) of example 1, wherein performing desiliconization demanganize on the test block Journey P4 and Gas Carburizing Process P5;And with the 10 corresponding test block (only gas carburizing) of axis according to comparative example 1, wherein Gas Carburizing Process P5 is only performed on the test block without performing desiliconization demanganize process P4.In addition, measuring and according to example 1 10 corresponding test block of axis and fatigue strength with the 10 corresponding test block of axis according to comparative example 1, i.e. nominal stress σ (MPa).In desiliconization demanganize process P4, in 8 times execution element removal processing of condition as escribed above.In addition, in II is tested, It is prepared for by the material identical with axis 10, i.e. SCR420 is formed and had the survey of scheduled shape (for example, Ф 18mm × 50mm) Test specimen only performs the test block Gas Carburizing Process P5 without performing desiliconization demanganize process P4, and the test block is held The polishing process gone by being machined the surface to remove test block, i.e. oxydic layer of grain boundary A.Therefore, be prepared for according to than Compared with the 10 corresponding test block of axis (gas carburizing+polishing) of example 2.Utilize the survey corresponding with the axis 10 according to comparative example 2 Test specimen measures fatigue strength.
The result for hereafter experiment II being described using Fig. 5 and Fig. 9.As shown in figure 5, in test block (according to the axis of example 1 10) in, compared to test block (according to the axis 10 of comparative example 1), suitably reduce Si included in the surface of test block With the content (mass percent) of Mn.Fig. 5 shows the result of the above-mentioned measurement using glow discharge emission spectrum.
In addition, as shown in fig. 6, the thickness of the oxydic layer of grain boundary A formed in test block (according to the axis 10 of example 1) is 4 μ The thickness of m, the oxydic layer of grain boundary A formed in test block (according to the axis 10 of comparative example 1) are 20 μm.Test block (according to The axis 10 of example 1) in, compared to test block (according to the axis 10 of comparative example 1), suitably reduce oxydic layer of grain boundary A.Pass through Surface and the test block of the test block (according to the axis 10 of example 1) shown in such as Fig. 7 and Fig. 8 are measured using light microscope The oxydic layer of grain boundary on the surface of (according to the axis 10 of comparative example 1) obtains the measured value of the thickness of the oxydic layer of grain boundary A of Fig. 6. The thickness of oxydic layer of grain boundary A is defined as the depth on the surface for observing grain boundaries away from test block.In fig. 8, it does not observe Oxydic layer of grain boundary A.
In addition, as shown in figure 9, when number of repetition Nf is about 107When, the nominal of test block (according to the axis 10 of example 1) Stress σ is about 580MPa, and the nominal stress σ of test block (according to the axis 10 of comparative example 2) is about 575MPa, and test block The nominal stress σ of (according to the axis 10 of comparative example 1) is about 515MPa.Therefore, with the 10 corresponding test of axis according to example 1 The fatigue strength of part is suitably higher than the fatigue strength with the 10 corresponding test block of axis according to comparative example 1.The measurement knot of Fig. 9 Fruit is obtained using for example small wild formula rotary bending fatigue test device.
According to experiment II's as a result, as shown in the measurement result of Fig. 5, it is corresponding with the axis 10 according to example 1, hold on it Gone in the test block of desiliconization demanganize process P4, it is corresponding compared to the axis 10 according to comparative example 1, do not perform on it is de- The test block of silicon demanganize process P4, the Si and the content (mass percent) of Mn included in test block surface are suitably subtracted It is few.It is therefore contemplated that Si that oxide (SiO, MnO) formed on the surface of axis 10 and Mn is caused to lead in Gas Carburizing Process P5 Cross desiliconization demanganize process P4 and from the surface evaporation of axis 10.
In addition, according to experiment II's as a result, as shown in the measurement result of Fig. 5 and Fig. 6, right with the axis 10 according to example 1 In test block answering, performing desiliconization demanganize process P4 on it, corresponding compared to the axis 10 according to comparative example 1, The test block of desiliconization demanganize process P4 is not performed on it, the Si and the content of Mn included in test block surface is suitably subtracted It is few, and the thickness of oxydic layer of grain boundary A formed in test block is adaptively reduced.It is therefore contemplated that by desiliconization demanganize Si and Mn is suitably reduced into the content of the Si and Mn in 10 surface of axis, and subtract from the surface evaporation of axis 10 in process P4 The amount included in carburizing gas and in subsequent gases carburizing process P5 with Si and the Mn O combined is lacked, so as to reduce The oxydic layer of grain boundary A formed on axis 10.
In addition, according to experiment II's as a result, as shown in the measurement result of Fig. 6 and Fig. 9, it is corresponding with the axis 10 according to example 1 Test block fatigue strength higher than fatigue strength with the 10 corresponding test block of axis according to comparative example 1, wherein described In example 1, the thickness of oxydic layer of grain boundary A is relatively thin (4 μm), in the comparative example 1, the thickness phase of oxydic layer of grain boundary A To thicker (20 μm).Show in addition, being higher than with the fatigue strength of the 10 corresponding test block of axis according to comparative example 2 with compared with The fatigue strength of the 10 corresponding test block of axis of example 1 wherein in the comparative example 2, is not carried out desiliconization demanganize process P4 And oxydic layer of grain boundary A is eliminated by polishing process.It is therefore contemplated that by reducing the oxydic layer of grain boundary A's formed on axis 10 Thickness improves the fatigue strength of axis 10.Additionally it is believed that in the manufacturing process according to the axis 10 of example 1, pair with compared with The 10 corresponding test block of axis of example 2 perform by being machined in the polishing process to remove oxydic layer of grain boundary A, be manufactured into This is than the manufacture cost higher of desiliconization demanganize process P4.It is therefore contemplated that in the manufacturing process P1 to P5 of the axis 10 according to example 1 In, perform the manufacture of the axis 10 according to comparative example 2 of polishing process compared to desiliconization demanganize process P4 is not carried out Journey suitably reduces manufacture cost.
In the manufacturing process P1 to P5 according to the axis 10 of example 1, before Gas Carburizing Process P5, compared with gas carburizing Process P5 temperature higher and pressure it is lower under conditions of perform desiliconization demanganize process P4.Therefore, before Gas Carburizing Process P5, Cause surface evaporation of the element of such as Si, Mn and Cr that oxide is formed from axis 10 in Gas Carburizing Process P5.Therefore, may be used Suitably to reduce the oxydic layer of grain boundary A formed on the surface of axis 10 during Gas Carburizing Process P5, so as to improve The fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, the desiliconization before Gas Carburizing Process P5 takes off In manganese process P4, such as Si, Mn or Cr that oxide is formed on the surface of axis 10 are caused during Gas Carburizing Process P5 Element is from the surface evaporation of axis 10.Therefore, the shape on the surface of axis 10 can suitably be reduced during Gas Carburizing Process P5 Into oxydic layer of grain boundary A.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, in desiliconization demanganize process P4, in pressure foot In enough subatmospheric vacuum, i.e., under the pressure of 100Pa to 1000Pa, cause oxide during Gas Carburizing Process P5 The element of such as Si, Mn or Cr on the surface of axis 10 are formed in from the surface evaporation of axis 10.Therefore, it can suitably reduce The oxydic layer of grain boundary A formed on the surface of axis 10 during Gas Carburizing Process P5, so as to improve the fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, oxidation is caused during Gas Carburizing Process P5 The element that object is formed is Mn, Si or Cr.Therefore, in desiliconization demanganize process P4, such as Mn, Si or Cr's has relatively high steam The element of pressure is from the surface evaporation of axis 10.Therefore, it can suitably reduce during Gas Carburizing Process P5 in the table of axis 10 The oxydic layer of grain boundary A formed on face.
In addition, in the manufacturing process P1 to P5 according to the axis 10 of example 1, after desiliconization demanganize process P4, temperature drop To the temperature of about 930 DEG C of Gas Carburizing Process P5 to perform Gas Carburizing Process P5.Therefore, desiliconization demanganize process P4 it After can continue to be appropriately performed Gas Carburizing Process P5.
Another example of the present invention is described below.In the following description, the component identical with above-mentioned example 1 is by phase Same reference number represents, it will not be repeated to describe.
According to the manufacturing process and manufacturing process P1 to the P5 substantially phases of the axis 10 according to example 1 of this exemplary ferrous metal part Together, in addition to gear 28 of the manufacture as the driving part used in such as vehicle rather than the axis 10 according to example 1.According to Figure 10 The shape of shown exemplary gas carburizing system 12 and the gas carburizing system 12 of example 1 according to figure 1 is slightly different. For example, there are different shapes according to this exemplary heater 20 and fixture 18 and example 1 but it is identical with example 1.
It is similar with the effect of above-mentioned example 1 in the manufacturing process according to exemplary gear 28, in desiliconization demanganize process P4 In, the oxydic layer of grain boundary A formed on the surface of gear 28 during Gas Carburizing Process P5 can be suitably reduced, so as to To improve the fatigue strength of gear 28.In addition, in order to manufacture gear 28, the peening for improving fatigue strength is usually performed Process.But in the manufacturing process according to this exemplary gear 28, due to suitably improving fatigue strength, so shot-peening Hardening process is unnecessary.Therefore, the manufacture cost of gear 28 can greatly be reduced.
More than, example of the invention is described with reference to attached drawing, but the present disclosure additionally applies for other embodiments.
In the manufacturing process P1 to P5 according to exemplary axis 10, in desiliconization demanganize process P4, such as Mn, Si or Cr's Element with opposite vapor pressure is suitably evaporated from the surface of axis 10.But other elements can also be from the table of axis 10 It is evaporated on face.In addition, by least one of surface evaporation Mn, Si and Cr from axis 10 elements, grain boundary oxidation can be inhibited The formation of layer A, so as to improve the fatigue strength of axis 10.
In addition, in the manufacturing process P1 to P5 according to exemplary axis 10, in desiliconization demanganize process P4, by using figure The result of experiment I shown in 4 carries out multiple regression analysis, obtains temperature T (DEG C) in desiliconization demanganize process P4, pressure Relationship between the content y (mass percent) of P (Pa) and Si, Mn and Cr in the surface of retention time t (min) and axis 10 Expression formula (1).However, for example, when the material of axis 10 becomes another kind from SCR420, it can be by using identical with the example Method later carry out multiple regression analysis carry out experiment I and obtain new relational expression.
In addition, in the examples described above, axis 10 and gear 28 used in vehicle are used as the example of ferrous metal part.However, The present disclosure additionally applies for other ferrous metal parts.That is, the present invention is suitable for performing it any ferrous metal part of Carburization Treatment.This Outside, in the examples described above, axis 10, i.e. ferrous metal part are formed by making ferrous material as main component comprising Fe, for example, by Steel material with C content for 0.02% to 2.14% (weight percent) is formed.However, ferrous metal part can be by containing with C The pure iron of less than 0.02% amount is formed.
Above-mentioned example is only exemplary, and the knowledge based on those skilled in the art can be that the present invention increases various repair Change and improve.

Claims (3)

1. a kind of method for manufacturing ferrous metal part, the method are characterized in that including:
Element removal processing is performed to the workpiece formed by ferrous material, wherein in element removal processing, in carburizing In the element of formation oxide on the surface of the workpiece by the surface evaporation from the workpiece during processing;And
After element removal processing, Surface hardening treatment is performed to the workpiece by Carburization Treatment, wherein
The element removal processing is performed under conditions of the Carburization Treatment higher temperature and lower pressure,
The element is at least one of Mn, Si and Cr.
2. according to the method described in claim 1, it is characterized in that
In element removal processing, the element is in a vacuum by the surface evaporation from the workpiece.
3. method according to claim 1 or 2, it is characterised in that
After element removal processing, the temperature of element removal processing be down to the temperature of the Carburization Treatment with Perform the Carburization Treatment.
CN201480067722.7A 2013-12-12 2014-12-08 The method for manufacturing ferrous metal part Expired - Fee Related CN105814230B (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2013257520A JP6171910B2 (en) 2013-12-12 2013-12-12 Manufacturing method of ferrous metal parts
JP2013-257520 2013-12-12
PCT/IB2014/002806 WO2015087154A1 (en) 2013-12-12 2014-12-08 Method of manufacturing ferrous metal component

Publications (2)

Publication Number Publication Date
CN105814230A CN105814230A (en) 2016-07-27
CN105814230B true CN105814230B (en) 2018-06-19

Family

ID=52273362

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201480067722.7A Expired - Fee Related CN105814230B (en) 2013-12-12 2014-12-08 The method for manufacturing ferrous metal part

Country Status (5)

Country Link
US (1) US20160305007A1 (en)
JP (1) JP6171910B2 (en)
CN (1) CN105814230B (en)
DE (1) DE112014005676T5 (en)
WO (1) WO2015087154A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6520547B2 (en) * 2015-08-10 2019-05-29 日本製鉄株式会社 Method of manufacturing test piece
EP3502302B1 (en) 2017-12-22 2022-03-02 Ge Avio S.r.l. Nitriding process for carburizing ferrium steels

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61163202A (en) * 1985-01-11 1986-07-23 Nippon Steel Corp Method for continuous desiliconization and desulfurization of molten iron
JPS61243104A (en) * 1985-04-17 1986-10-29 Nippon Jiryoku Senko Kk Method for producing steel shot material
JPS63145701A (en) * 1986-12-08 1988-06-17 Toyota Motor Corp Method for sintering stainless steel powder
JPH05171348A (en) 1991-12-20 1993-07-09 Aichi Steel Works Ltd Carburizing steel excellent in impact fatigue strength
JPH0853711A (en) * 1994-08-11 1996-02-27 Kobe Steel Ltd Surface hardening treating method
TW336257B (en) * 1996-01-30 1998-07-11 Daido Hoxan Inc A method of carburizing austenitic stainless steel and austenitic stainless steel products obtained thereby
JPH09302454A (en) * 1996-05-13 1997-11-25 Toyota Central Res & Dev Lab Inc Pre-treatment of carburizing quenched material and manufacture thereof
JP3486506B2 (en) * 1996-06-03 2004-01-13 光洋精工株式会社 Gas carburizing method
CN1203959A (en) * 1997-04-29 1999-01-06 奥瓦科钢铁股份公司 Case hardening steel
JP3442737B2 (en) * 2000-12-11 2003-09-02 中外炉工業株式会社 Vacuum carburizing method for steel parts containing Cr and / or Mn
US20050011192A1 (en) * 2001-05-10 2005-01-20 Shinjiroh Ohishi Surface-reformed exhaust gas guide assembly of vgs type turbo charger, and method surface-reforming component member thereof
CN101184860B (en) * 2005-04-28 2011-01-19 爱信艾达株式会社 Carburized induction-hardened component
JP4327781B2 (en) * 2005-09-12 2009-09-09 Ntn株式会社 Manufacturing method of carburized parts
US20120251377A1 (en) * 2011-03-29 2012-10-04 Kuen-Shyang Hwang Method for enhancing strength and hardness of powder metallurgy stainless steel
CN102352478B (en) * 2011-10-31 2013-02-20 北京机电研究所 Automatic telescopic carburizing gas nozzle device of vacuum low pressure carburizing device

Also Published As

Publication number Publication date
US20160305007A1 (en) 2016-10-20
JP6171910B2 (en) 2017-08-02
DE112014005676T5 (en) 2016-10-06
CN105814230A (en) 2016-07-27
JP2015113509A (en) 2015-06-22
WO2015087154A1 (en) 2015-06-18

Similar Documents

Publication Publication Date Title
US9783879B2 (en) Nitrided steel member and manufacturing method thereof
WO2010041561A1 (en) Process for production of carburized part and steel part
CN105899697A (en) Carburized-steel-component production method, and carburized steel component
CN105264104B (en) Carburized component and its manufacture method
CN113862610B (en) Pretreatment method for improving corrosion resistance of carburized layer
US20160108490A1 (en) Gear and method for manufacturing the same
CN107849679B (en) Nitrided steel member and method for producing same
CN111500970A (en) Carbonitriding process for chain pin shaft
CN105814230B (en) The method for manufacturing ferrous metal part
KR101719560B1 (en) Heat treatment method for surface hardened alloy steel
JP6448529B2 (en) Steel wire with excellent coiling property and method for producing the same
JP5405325B2 (en) Differential gear and manufacturing method thereof
JP6587886B2 (en) Manufacturing method of nitrided steel member
RU2291227C1 (en) Construction-steel parts surface hardening method
JP6225510B2 (en) Vacuum carburizing and nitriding method
US11359271B2 (en) Nitriding treatment method of steel member
JP5821512B2 (en) NITRIDED COMPONENT AND MANUFACTURING METHOD THEREOF
JP2006183095A (en) Method for producing gear excellent in fatigue strength on tooth surface
JP6344495B1 (en) Vacuum carburizing and nitriding treatment method for steel
JP2016074951A (en) Manufacturing method of case hardened steel
JP2015010258A (en) CARBURIZING METHOD OF HIGH-Si STEEL FOR CARBURIZING
KR102360964B1 (en) Complex heat treatment method of steel for gear
JP6493470B2 (en) Vacuum carburizing and nitriding method
JP4858071B2 (en) Steel surface treatment method and surface-treated steel material
JP2020111802A (en) Method for manufacturing surface hardened steel component

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20180619