CN104117830A - Gear production technology facilitating gear surface quality and segregation degree - Google Patents
Gear production technology facilitating gear surface quality and segregation degree Download PDFInfo
- Publication number
- CN104117830A CN104117830A CN201410354561.1A CN201410354561A CN104117830A CN 104117830 A CN104117830 A CN 104117830A CN 201410354561 A CN201410354561 A CN 201410354561A CN 104117830 A CN104117830 A CN 104117830A
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- Prior art keywords
- gear
- blank
- surface quality
- degree
- conducive
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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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/14—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass gear parts, e.g. gear wheels
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- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/32—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for gear wheels, worm wheels, or the like
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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
- C23C8/08—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
- 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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F17/00—Multi-step processes for surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by subclass C21D or C22F or class C25
Abstract
The invention discloses a gear production technology facilitating the gear surface quality and the segregation degree. The gear production technology includes the steps of blank casting, cutting, heat treatment, finishing cutting and grinding in sequence. A bar is made of 20 CrMnTiH. The step of heat treatment comprises the steps that a cut blank is carbonized, the cut blank is slowly cooled after being carbonized, the second time of heating is conducted when the blank is slowly cooled to be not higher than 550 DEG C, quenching is conducted after heat preservation is conducted for at least 2 h, the third time of heating is conducted on the quenched blank until the blank reaches the temperature of 170-200 DEG C, heat preservation is conducted for at least 3 h, tempering is conducted, the blank is heated to the temperature of 840-870 DEG C in the second time of heating, and the carburization treatment includes a preheating stage, a strong carburization stage and a diffusion stage in sequence. According to the gear production technology facilitating the gear surface quality and the segregation degree, the steps are simple, product components are even, and a gear which is high in shock resistance capability, resistant to wear and proper in strength can be conveniently obtained, wherein a surface hardened layer of the gear is not prone to disengagement.
Description
Technical field
The present invention relates to the drive disk assembly manufacturing process for transmission of torque, particularly relate to a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation.
Background technology
Gear is the critical component in plant equipment, and the quality of gear quality is directly connected to the service life of whole equipment.And the quality of gear quality depends on gear material and Technology for Heating Processing thereof to a great extent.Therefore, the producer relevant to gear manufacture all very payes attention to the research and development of gear material and heat treatment technics thereof both at home and abroad.
The material of prior art middle gear is selected the generally stressed and working environment in transmission system according to gear, and Technology for Heating Processing is that the corrosion resistance that guarantees gear surface thin hardened layer, gear surface and centre hardness, gear meets the means of technological requirement.The higher grade of product martensite metallographic that the heat treatment that is 20CrMnTiH gear for material in prior art obtains, in use very easily there is under external force work hardening in the gear obtaining like this, causing gear that superficial layer occurs within a short period of time departs from, have a strong impact on gear-driven stability and service life, although efficient by adopting the mode of strand to obtain gear blank, but C content difference is larger on tooth bar and the flank of tooth, affects gear life and further improve.
Summary of the invention
The higher grade of product martensite metallographic obtaining for the heat treatment that is 20CrMnTiH gear for material in above-mentioned prior art, in use very easily there is under external force work hardening in the gear obtaining like this, causing gear that superficial layer occurs within a short period of time departs from, have a strong impact on gear-driven stability and service life, although efficient by adopting the mode of strand to obtain gear blank, but on tooth bar and the flank of tooth, C content difference is larger, affect the problem that gear life further improves, the invention provides a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation.
For the problems referred to above, a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation provided by the invention reaches goal of the invention by following technical essential: a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 830-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, after Carburization Treatment, carry out Slow cooling, blank Slow cooling heats for the second time when not higher than 550 ℃ and is incubated after being no less than 2h and quenches, blank after quenching is heated to 170-200 ℃ and insulation to be for the third time no less than 3h and to carry out tempering, describedly be heated to be blank is heated to 840-870 ℃ for the second time, described Carburization Treatment comprises the warm-up phase successively carrying out, surging carburizing stage and diffusion phase,
Described warm-up phase is total to hot 20-30min for blank being placed in to methyl alcohol and the propane gas of 830-860 ℃, the described surging carburizing stage is warming up to 875-920 ℃ by the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment and keeps 2-3h, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.0-1.15%, described diffusion phase is to 830-880 ℃ of maintenance 1.5-2h by the blank in surging carburizing stage, methyl alcohol and propane gas environment temperature reduction, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
Further technical scheme is:
Between described machining and heat treatment, also comprise oil removing cleaning step.
The oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
Between described heat treatment and essence cutting, also comprise the bead that is no less than 15min.
Described Slow cooling is that stove is cold.
To the heating for the second time of blank and be incubated blank and be arranged in restitutive protection's gaseous environment.
To blank heat for the second time and be incubated after quenching be oil cooling.
Between described oil cooling and tempering step, also comprise cleaning step.
The present invention has following beneficial effect:
1, ring gauge manufacturing approach craft provided by the invention is simple, the energy resource consumption of Technology for Heating Processing only has more 20% compared to prior art, but the metallographic structure crystal grain of final gear product has obtained refinement, gear product martensitic structure metallographic grade is 3, compared to prior art, adopt gear martensitic structure metallographic grade that this material obtains 2-3 the grade that declined, simultaneously, by above Technology for Heating Processing, the gear surface hardness obtaining remains on 59-60HRC, it is upper that centre hardness grade remains on 35-36HRC, and case-hardening layer thickness is 1.2-1.4mm.Above product gear parameter makes the in use difficult disengaging of cementation zone of gear, gear impact resistance, wearability and intensity suitable, and the 5-7 that be the gear that the existing Technology for Heating Processing of employing obtains on an equal basis the service life of gear doubly.
2, this process route adopts Carburization Treatment temperature parameter and each duration in stage, be convenient to realize the enough quenching degree of blank, little superheated susceptivity, good carburizing ability, the residual austenite content after heat treatment is few, carburizing and quenching deflection is little.
3, the M-EMS adopting in strand process, the alternating magnetic field that agitator excites is penetrated in the molten steel of strand, just induces therein electric current, and this induced-current and local magnetic field interaction produce electromagnetic force, act on molten steel volume element, thereby can promote molten steel motion.In the gear blank that the parameter of electromagnetic agitation is selected to make to obtain, the degree of segregation of Cr, Mn, C is respectively in 0.05,0.05 and 0.085 left and right, the electromagnetic agitation generally adopting compared to prior art, the degree of segregation drop-out value of Cr, Mn, C is respectively 0.035,0.02 and 0.035 left and right, be the selection of above technological parameter even the distribution of each component in gear blank, the uniformity that is conducive to mechanical property and wearability on the same working face of gear, is beneficial to life-span of gear.
The specific embodiment
Below in conjunction with embodiment, the present invention is described in further detail, but structure of the present invention is not limited only to following examples.
Embodiment 1:
A kind of Gear Production technique that is conducive to gear surface quality and degree of segregation, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 830-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, after Carburization Treatment, carry out Slow cooling, blank Slow cooling heats for the second time when not higher than 550 ℃ and is incubated after being no less than 2h and quenches, blank after quenching is heated to 170-200 ℃ and insulation to be for the third time no less than 3h and to carry out tempering, describedly be heated to be blank is heated to 840-870 ℃ for the second time, described Carburization Treatment comprises the warm-up phase successively carrying out, surging carburizing stage and diffusion phase,
Described warm-up phase is total to hot 20-30min for blank being placed in to methyl alcohol and the propane gas of 830-860 ℃, the described surging carburizing stage is warming up to 875-920 ℃ by the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment and keeps 2-3h, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.0-1.15%, described diffusion phase is to 830-880 ℃ of maintenance 1.5-2h by the blank in surging carburizing stage, methyl alcohol and propane gas environment temperature reduction, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
Ring gauge manufacturing approach craft provided by the invention is simple, the energy resource consumption of Technology for Heating Processing only has more 20% compared to prior art, but the metallographic structure crystal grain of final gear product has obtained refinement, gear product martensitic structure metallographic grade is 3, compared to prior art, adopt gear martensitic structure metallographic grade that this material obtains 2-3 the grade that declined, simultaneously, by above Technology for Heating Processing, the gear surface hardness obtaining remains on 59-60HRC, it is upper that centre hardness grade remains on 35-36HRC, and case-hardening layer thickness is 1.2-1.4mm.Above product gear parameter makes the in use difficult disengaging of cementation zone of gear, gear impact resistance, wearability and intensity suitable, and the 5-7 that be the gear that the existing Technology for Heating Processing of employing obtains on an equal basis the service life of gear doubly.
The Carburization Treatment temperature parameter that this process route adopts and each duration in stage, be convenient to realize the enough quenching degree of blank, little superheated susceptivity, good carburizing ability, the residual austenite content after heat treatment is few, carburizing and quenching deflection is little.
The M-EMS adopting in strand process, the alternating magnetic field that agitator excites is penetrated in the molten steel of strand, just induces therein electric current, and this induced-current and local magnetic field interaction produce electromagnetic force, act on molten steel volume element, thereby can promote molten steel motion.In the gear blank that the parameter of electromagnetic agitation is selected to make to obtain, the degree of segregation of Cr, Mn, C is respectively in 0.05,0.05 and 0.085 left and right, the electromagnetic agitation generally adopting compared to prior art, the degree of segregation drop-out value of Cr, Mn, C is respectively 0.035,0.02 and 0.035 left and right, be the selection of above technological parameter even the distribution of each component in gear blank, the uniformity that is conducive to mechanical property and wearability on the same working face of gear, is beneficial to life-span of gear.
Embodiment 2:
The present embodiment is further qualified on the basis of embodiment 1, for the oil pollution that in process route between elimination machining, plant equipment or environment cause blank, avoid greasy dirt to affect thermal effectiveness, between described machining and heat treatment, also comprise oil removing cleaning step.
For obtaining good oil removing cleaning performance and cleaning efficiency, the oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
For further strengthening the surface quality of product, between described heat treatment and essence cutting, also comprise the bead that is no less than 15min.
For preventing that in cooling procedure, oxidizing gas etc. impacts the surface of blank, described Slow cooling is that stove is cold.Further, to the heating for the second time of blank and be incubated blank and be arranged in restitutive protection's gaseous environment.Further, blank is heated for the second time and be incubated after quenching be oil cooling.
For avoiding tempering effect to be subject to the impact of other factors, between described oil cooling and tempering step, also comprise cleaning step.
Above content is the further description of the present invention being done in conjunction with concrete preferred embodiment, can not assert that the specific embodiment of the present invention is confined to these explanations.For general technical staff of the technical field of the invention, not departing from other embodiments that draw under technical scheme of the present invention, all should be included in protection scope of the present invention.
Claims (8)
1. a Gear Production technique that is conducive to gear surface quality and degree of segregation, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, it is characterized in that, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 830-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, after Carburization Treatment, carry out Slow cooling, blank Slow cooling heats for the second time when not higher than 550 ℃ and is incubated after being no less than 2h and quenches, blank after quenching is heated to 170-200 ℃ and insulation to be for the third time no less than 3h and to carry out tempering, describedly be heated to be blank is heated to 840-870 ℃ for the second time, described Carburization Treatment comprises the warm-up phase successively carrying out, surging carburizing stage and diffusion phase,
Described warm-up phase is total to hot 20-30min for blank being placed in to methyl alcohol and the propane gas of 830-860 ℃, the described surging carburizing stage is warming up to 875-920 ℃ by the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment and keeps 2-3h, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.0-1.15%, described diffusion phase is to 830-880 ℃ of maintenance 1.5-2h by the blank in surging carburizing stage, methyl alcohol and propane gas environment temperature reduction, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
2. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 1, is characterized in that, also comprises oil removing cleaning step between described machining and heat treatment.
3. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 2, is characterized in that, the oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
4. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 1, is characterized in that, between described heat treatment and essence cutting, also comprises the bead that is no less than 15min.
5. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 1, is characterized in that, described Slow cooling is that stove is cold.
6. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 1, is characterized in that, to the heating for the second time of blank and be incubated blank and be arranged in restitutive protection's gaseous environment.
7. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 1, is characterized in that, to blank heat for the second time and be incubated after quenching be oil cooling.
8. a kind of Gear Production technique that is conducive to gear surface quality and degree of segregation according to claim 7, is characterized in that, also comprises cleaning step between described oil cooling and tempering step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410354561.1A CN104117830A (en) | 2014-07-24 | 2014-07-24 | Gear production technology facilitating gear surface quality and segregation degree |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410354561.1A CN104117830A (en) | 2014-07-24 | 2014-07-24 | Gear production technology facilitating gear surface quality and segregation degree |
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| CN104117830A true CN104117830A (en) | 2014-10-29 |
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| CN201410354561.1A Pending CN104117830A (en) | 2014-07-24 | 2014-07-24 | Gear production technology facilitating gear surface quality and segregation degree |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104498696A (en) * | 2014-12-15 | 2015-04-08 | 中国南方航空工业(集团)有限公司 | Heat treatment method of gear parts |
| CN106222605A (en) * | 2016-08-29 | 2016-12-14 | 盐城圣奥热处理有限公司 | A kind of gear carburizing quenching process |
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| CN104498696A (en) * | 2014-12-15 | 2015-04-08 | 中国南方航空工业(集团)有限公司 | Heat treatment method of gear parts |
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