CN104372288A - Gear with high surface hardness, high wearing resistance and high tenacity and treating furnace of gear - Google Patents
Gear with high surface hardness, high wearing resistance and high tenacity and treating furnace of gear Download PDFInfo
- Publication number
- CN104372288A CN104372288A CN201410695525.1A CN201410695525A CN104372288A CN 104372288 A CN104372288 A CN 104372288A CN 201410695525 A CN201410695525 A CN 201410695525A CN 104372288 A CN104372288 A CN 104372288A
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- China
- Prior art keywords
- gear
- heating furnace
- surface hardness
- working lining
- tenacity
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- 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
- C23C8/28—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 more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
-
- 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
- C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
- C23C10/18—Solid state diffusion of only metal elements or silicon into metallic material surfaces using liquids, e.g. salt baths, liquid suspensions
-
- 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
- C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention relates to a gear with high surface hardness, high wearing resistance and high tenacity and a treating furnace of the gear. The gear comprises a gear matrix, and is characterized in that a compound coating is arranged on the surface of the gear matrix, the compound coating is formed by connecting a working layer and a middle gradient layer, the working layer and the middle gradient layer are in alloying connection, and the middle gradient layer and the gear matrix are in alloying connection. The surface layer hardness of the gear disclosed by the invention is between HV800-2000 (and the precision of the hardness can be controlled within +/-5% according to requirement), and high hardness is obtained; the coating thickness is within 0.1-2mm (adjustable), and the coating is thick so as to obtain high abrasive resistance and tenacity; since the coating is thick, the buffer capacity is enhanced, and the gear service is greatly prolonged, and is doubled above on the existing basis. The manufacturing method is simple and easy to operate, the manufacturing efficiency is high, and the mass production requirement can be satisfied.
Description
Technical field
The present invention relates to a kind of gear and process stove thereof, especially obtain gear and the heat treatment furnace thereof of high surface hardness, high-wearing feature and high tenacity.
Background technology
As everyone knows, utilize low-carbon (LC) or medium carbon alloy steel to manufacture gear, multiplex Surface thermo-chemical treatment after gear forming processing at present both at home and abroad more, as heat treating methods such as surface modification technologies and surface induction heating, as: C is oozed on surface, nitrogenize, and C, N ooze altogether, ion nitriding and PVD, CVD, PCVD, TD, the technology such as gear surface ball blast, and laser, ion implantation, the surface treatment method such as plasma treatment, electron beam molecule extension.But to so far, there is following shortcoming in above-mentioned various method:
Although 1. the conventional infiltration method that expands can reach desirable coat-thickness and bonding force, general lower hardness is about HR60;
2. and in recent years the additive method be born, the coating of acquisition is too thin, generally at below 10um, and coating and basal body binding force and wear resistance very poor;
3. due to equipment degree of precision and higher vacuum restriction, be difficult to produce in enormous quantities, the workpiece that particularly size is large then required equipment is abnormal huge, otherwise can not meet requirement of engineering.
Therefore the treatment process of prior art, can not obtain high surface hardness, high-wearing feature, high tenacity and the gear of high life, can not meet the needs of market and user.
Summary of the invention
The present invention is directed to the deficiency that prior art can not obtain high surface hardness, high-wearing feature, high tenacity and the gear of high life, its object is to gear and process stove thereof that a kind of high surface hardness, high-wearing feature and high tenacity are provided.
To achieve these goals, this patent is by the following technical solutions:
The gear of a kind of high surface hardness, high-wearing feature and high tenacity, comprise gear matrix, it is characterized in that, gear matrix surface is provided with compound coating, described compound coating is connected and composed by working lining, Middle-gradient layer, the laminated aurification of working lining, Middle-gradient connects, and Middle-gradient layer is connected with gear basic asphalt mixture.
Further feature is: described Middle-gradient layer, be [C], [N] active atomic by workpiece substrate Surface absorption, gradually to internal diffusion, form C, N Middle-gradient layer on workpiece substrate surface.
Further feature is: described working lining, be the one of Cr, Nb, V, B, Ti element, two kinds or three kinds, four kinds or five kinds, respective compound or salt, decompose at a certain temperature, forms the lewis' acid of Cr, Nb, V, B, Ti; Fe and C of these lewis' acids and matrix steel grade forms the working lining of high strength and high rigidity.
The process stove of the gear of high surface hardness, high-wearing feature and high tenacity, comprise the heating furnace body of sealing, it is characterized in that: the middle cavity of described heating furnace body forms heating furnace, on heating furnace body, be provided with temperature probe, vacuum degree measurement probe, the termination of temperature probe, vacuum degree measurement probe all passes in heating furnace, or is communicated with heating furnace; On heating furnace body, be provided with and vacuumize the pump housing, the pipeline vacuumizing the pump housing passes in heating furnace, is forced outwards to take out by the gas in heating furnace, forms vacuum; On heating furnace body, be provided with one or more interlayer component input channel, under slave mode, the component that the process of Middle-gradient layer needs added in heating furnace separately respectively; On heating furnace body, be provided with one or more working lining component input channel, under slave mode, the component that working lining process needs added in heating furnace separately respectively.
In heating furnace, be provided with cover, cover is connected with the pipeline of interlayer component input channel, and first the gaseous fraction added enters in cover.
Arrange a workpiece stage in the bottom of heating furnace, pending gear workpieces is placed on workpiece stage.
On heating furnace body, be provided with water discharge valve, vent valve, be all communicated with heating furnace.
High surface hardness of the present invention, high-wearing feature, high tenacity and the gear of high life and process stove thereof, relative to prior art, have following features:
Gear of the present invention adopts traditional conventional gear manufactured materials and forming and machining method, adopts novel electrovacuum compound surface thermal treatment to expand and oozes intensifying technology:
1, make gear surface layer hardness (precision of hardness can be controlled on request within ± 5%) between HV800 ~ 2000, obtain higher hardness;
2, coat-thickness (adjustable) within 0.1 ~ 2mm, coating is thicker, obtains higher wear resistance and toughness;
3, coating is thicker, enhances surge capability, and gear life increases substantially, and existing basis is enhanced about more than once.
4, manufacture method is simple, easily operates; And it is higher to manufacture efficiency, meet the needs of batch production.
Accompanying drawing explanation
Fig. 1 is gear structure sectional view of the present invention;
Fig. 2 is gear process furnace structure sectional view of the present invention.
Embodiment
The gear of high surface hardness of the present invention, high-wearing feature and high tenacity, comprise gear matrix 21, on gear matrix 21 surface, there is compound coating, compound coating is connected and composed by working lining 23, Middle-gradient layer 22, between working lining 23, Middle-gradient layer 22, alloying connects, and Middle-gradient layer 22 is connected with gear matrix 21 alloying.
The present invention adopts the method for thermodiffusion on the surface of steel gear, make gear surface form the element heat expansions such as C, N, a Re and ooze metallurgical bonding layer, using this layer as Middle-gradient transition layer, and then the expansion of continuation heat is oozed on this layer, strong carbide forming element B, V, Cr, Nb, Ti etc., make it the high hardness wear-resisting working lining formed and Middle-gradient transition layer is combined closely.Therefore this compound coating of the present invention is made up of the working lining on surface, Middle-gradient layer and matrix, is metallurgical binding between each layer.
Due to C, the element that the atomic radiuses such as N are less can form interstitial solid solution in Fe, be easy to spread in steel, generally, when solute is identical with the lattice type of solvent metal, also large solid solubility is easily obtained, as Ti, Nb, V, Cr etc., Fe and C of these elements and matrix steel grade forms the compound of high strength and high rigidity to increase gear surface hardness and wear resistance.Kerosene is instilled in process furnace, or benzene, methyl alcohol, simultaneously logical ammonia in stove, then produce following chemical reaction:
CH4+NH3≒HCN+3H2
CO+NH3≒HCN+H2O
2HCN≒H2+2[C]+2[N]
Then [C], [N] active atomic are absorbed by workpiece surface, gradually to internal diffusion, form C, N Middle-gradient layer.This layer can change the requirement that processing parameter (temperature, time, concentration etc.) reaches expection.
Then compound (as oxide compound, muriate etc.) containing elements such as Cr, Nb, V, B, Ti or salt are at high temperature provided, then continue in workpiece surface diffusion, and undertaken by Fick's second law rule:
In formula: D is spread coefficient, cm2/s
: for infiltrating element concentration gradient in the x-direction
; For after the t time, the concentration of reactant.
The principal element affecting rate of diffusion has temperature, matrix alloy composition, penetration enhancer atomic percent, crystalline network etc., and the pass of spread coefficient and temperature is:
In formula: D0 diffusion constant: R gas law constant: Q diffusion intensifies energy: T is thermodynamic temperature.Use as working condition requirement by gear, and combination gear failure cause analysis, coating structure reasonable in design, then reasonably controls above-mentioned working parameter, makes it to reach design requirements.
As shown in Figure 2, gear process stove of the present invention, comprise the heating furnace body 1 of sealing, the middle cavity of heating furnace body 1 forms heating furnace 2, pending gear workpieces is placed in heating furnace 2, or a workpiece stage 3 is set in the bottom of heating furnace 2, pending gear workpieces is placed on workpiece stage 3; On heating furnace body 1, be provided with temperature probe 4, vacuum degree measurement probe 5, the termination of temperature probe 4, vacuum degree measurement probe 5 all passes in heating furnace 2, or is communicated with heating furnace 2, respectively measuring tempeature (control temperature) or vacuum tightness; On heating furnace body 1, be provided with and vacuumize the pump housing 6, the pipeline vacuumizing the pump housing 6 passes in heating furnace 2, starts after vacuumizing the pump housing 6, is forced outwards to take out by the gas in heating furnace 2, forms vacuum.On heating furnace body 1, be provided with one or more interlayer component input channel 7, under slave mode, the component that the process of Middle-gradient layer needs is added in heating furnace 2 separately respectively, in interlayer component input channel 7, be provided with necessary controller, control valve, storage tank body etc., open according to processing requirement, and this component is added.The component needed due to the process of Middle-gradient layer contains gas, therefore is provided with cover 8 in heating furnace 2, and cover 8 is connected with the pipeline of interlayer component input channel 7, and first the gaseous fraction added enters in cover 8, from top to bottom near pending gear workpieces; On heating furnace body 1, be provided with one or more working lining component input channel 9, under slave mode, the component that working lining process needs is added in heating furnace 2 separately respectively, in working lining component input channel 9, be provided with necessary controller, control valve, storage tank body etc., open according to processing requirement, and this component is added.Often organizing component is preferably placed in a component input channel, and often kind of component adds in heating furnace 2 separately under slave mode.The heating arrangement of heating furnace body 1 can adopt prior art, as electrically heated, gas heating etc., reaches the temperature of processing requirement.
On heating furnace body 1, be provided with water discharge valve 10 and vent valve 11, be all communicated with heating furnace 2; After opening as required, the water of heating furnace 2 or gas are discharged.
Workpiece 2 is placed in heating furnace 2, or be placed on workpiece stage 3, startup vacuumizes the pump housing 6 and vacuumizes and heat, interlayer component input channel 7 is opened simultaneously, the work of middle expansion permeation atmosphere producer, adds the middle component expanding permeation atmosphere needs forming middle layer in burner hearth 2, and the temperature range inside holding certain hour of specifying, when after the processing requirement reaching certain expansion alloying layer thickness, close this interlayer component input channel 7; And open working lining component input channel 9, working lining is expanded the component of oozing needs and adds in burner hearth 2, after reaching processing parameter, closing device, takes out workpiece and proceeds to following operation thermal treatment, as Quench and temper process, obtain gear workpieces; This gear workpieces can assemble use.
This equipment can select Middle-gradient layer and the kind of working lining and the thickness of this layer by calculating and design requirements, and can adjust by service requirements.
What finally illustrate is; above embodiment is only in order to illustrate technical scheme of the present invention and unrestricted; although with reference to preferred embodiment to invention has been detailed description; those of ordinary skill in the art should be appreciated that the replacement/amendment for not departing from technical solution of the present invention all should fall among the scope of protection of present invention.
Claims (7)
1. the gear of a high surface hardness, high-wearing feature and high tenacity, comprise gear matrix, it is characterized in that, gear matrix surface is provided with compound coating, described compound coating is connected and composed by working lining, Middle-gradient layer, the laminated aurification of working lining, Middle-gradient connects, and Middle-gradient layer is connected with gear basic asphalt mixture.
2. the gear of high surface hardness according to claim 1, high-wearing feature and high tenacity, it is characterized in that: described Middle-gradient layer, be [C], [N] active atomic by workpiece substrate Surface absorption, gradually to internal diffusion, form C, N Middle-gradient layer on workpiece substrate surface.
3. the gear of high surface hardness according to claim 1 and 2, high-wearing feature and high tenacity, it is characterized in that: described working lining, be the one of Cr, Nb, V, B, Ti element, two kinds or three kinds, four kinds or five kinds, respective compound or salt, decompose at a certain temperature, form the lewis' acid of Cr, Nb, V, B, Ti; Fe and C of these lewis' acids and matrix steel grade forms the working lining of high strength and high rigidity.
4. the process stove of the gear of high surface hardness, high-wearing feature and high tenacity, comprise the heating furnace body (1) of sealing, it is characterized in that: the middle cavity of described heating furnace body (1) forms heating furnace (2), on heating furnace body (1), be provided with temperature probe (4), vacuum degree measurement probe (5), the termination of temperature probe (4), vacuum degree measurement probe (5) all passes in heating furnace (2), or is communicated with heating furnace (2); On heating furnace body (1), be provided with and vacuumize the pump housing (6), the pipeline vacuumizing the pump housing (6) passes in heating furnace (2), is forced outwards to take out by the gas in heating furnace (2), forms vacuum; On heating furnace body (1), be provided with one or more interlayer component input channel (7), under slave mode, the component that the process of Middle-gradient layer needs added in heating furnace (2) separately respectively; On heating furnace body (1), be provided with one or more working lining component input channel (9), under slave mode, the component that working lining process needs added in heating furnace (2) separately respectively.
5. the process stove of the gear of high surface hardness, high-wearing feature and high tenacity according to claim 4, it is characterized in that: in heating furnace (2), be provided with cover (8), cover (8) is connected with the pipeline of interlayer component input channel (7), and first the gaseous fraction added enters in cover (8).
6. the process stove of the gear of high surface hardness, high-wearing feature and high tenacity according to claim 4, is characterized in that: arrange a workpiece stage (3) in the bottom of heating furnace (2), pending gear workpieces is placed on workpiece stage (3).
7. according to the process stove of the gear of the arbitrary described high surface hardness of claim 4-6, high-wearing feature and high tenacity, it is characterized in that: on heating furnace body (1), be provided with water discharge valve (10) and vent valve (11), be all communicated with heating furnace (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410695525.1A CN104372288A (en) | 2014-11-27 | 2014-11-27 | Gear with high surface hardness, high wearing resistance and high tenacity and treating furnace of gear |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410695525.1A CN104372288A (en) | 2014-11-27 | 2014-11-27 | Gear with high surface hardness, high wearing resistance and high tenacity and treating furnace of gear |
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| CN104372288A true CN104372288A (en) | 2015-02-25 |
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| CN201410695525.1A Pending CN104372288A (en) | 2014-11-27 | 2014-11-27 | Gear with high surface hardness, high wearing resistance and high tenacity and treating furnace of gear |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105651638A (en) * | 2016-03-21 | 2016-06-08 | 重庆微世特机电设备有限公司 | Fatigue testing device of material under thermal-mechanical coupling effect |
| CN107058941A (en) * | 2017-05-16 | 2017-08-18 | 重庆理工大学 | Infiltration method and device are expanded in the heating of gear surface vacuum induction |
| CN107761002A (en) * | 2017-09-12 | 2018-03-06 | 青岛理工大学 | A kind of double material powder forging gear with gradient layer and preparation method thereof |
| CN111519130A (en) * | 2020-05-13 | 2020-08-11 | 重庆理工大学 | Chemical preparation device and method for gear surface solid lubricating coating |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1128301A (en) * | 1995-11-07 | 1996-08-07 | 北京航空航天大学 | Composite impregnation-plating method |
| CN101195913A (en) * | 2007-01-25 | 2008-06-11 | 桂林电子科技大学 | Technique for forming chromium carbon nitrogen surface alloying layer by plasma composite process low-temperature |
| CN101418451A (en) * | 2008-11-19 | 2009-04-29 | 郑州航空工业管理学院 | Carbonitriding-deep Re-B-C-N penetration composite heat treating process |
| CN204281805U (en) * | 2014-11-27 | 2015-04-22 | 重庆理工大学 | The process stove of a kind of surperficial high strength, high-wearing feature and high tenacity gear |
-
2014
- 2014-11-27 CN CN201410695525.1A patent/CN104372288A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1128301A (en) * | 1995-11-07 | 1996-08-07 | 北京航空航天大学 | Composite impregnation-plating method |
| CN101195913A (en) * | 2007-01-25 | 2008-06-11 | 桂林电子科技大学 | Technique for forming chromium carbon nitrogen surface alloying layer by plasma composite process low-temperature |
| CN101418451A (en) * | 2008-11-19 | 2009-04-29 | 郑州航空工业管理学院 | Carbonitriding-deep Re-B-C-N penetration composite heat treating process |
| CN204281805U (en) * | 2014-11-27 | 2015-04-22 | 重庆理工大学 | The process stove of a kind of surperficial high strength, high-wearing feature and high tenacity gear |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105651638A (en) * | 2016-03-21 | 2016-06-08 | 重庆微世特机电设备有限公司 | Fatigue testing device of material under thermal-mechanical coupling effect |
| CN107058941A (en) * | 2017-05-16 | 2017-08-18 | 重庆理工大学 | Infiltration method and device are expanded in the heating of gear surface vacuum induction |
| CN107058941B (en) * | 2017-05-16 | 2019-05-03 | 重庆理工大学 | Infiltration method and device are expanded in the heating of gear surface vacuum induction |
| CN107761002A (en) * | 2017-09-12 | 2018-03-06 | 青岛理工大学 | A kind of double material powder forging gear with gradient layer and preparation method thereof |
| CN111519130A (en) * | 2020-05-13 | 2020-08-11 | 重庆理工大学 | Chemical preparation device and method for gear surface solid lubricating coating |
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Application publication date: 20150225 |