CN104439993A - Gear casting production process - Google Patents
Gear casting production process Download PDFInfo
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- CN104439993A CN104439993A CN201410678967.5A CN201410678967A CN104439993A CN 104439993 A CN104439993 A CN 104439993A CN 201410678967 A CN201410678967 A CN 201410678967A CN 104439993 A CN104439993 A CN 104439993A
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- Prior art keywords
- gear
- temperature
- methyl alcohol
- finished product
- phase
- Prior art date
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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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
-
- 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
Abstract
The invention discloses a gear casting production process which includes the following steps that (1) a raw material formula is provided, wherein raw materials comprise, by mass, 0.17% to 0.20% of C, 3.2% to 4.0% of Mn, 0.045% to 0.044% of S, 0.04% to 0.05% of P and the balance iron; (2) the raw materials in the raw material formula in the step (1) are stirred and evenly mixed according to the ratio and put into a smelter, so that the raw materials are smelted at high temperature, wherein the smelting temperature ranges from 400 DEG C to 500 DEG C; smelting time ranges from 3 h to 6 h, and the raw materials are stirred once every 30 min to 45 min and stirred for 1 min to 3 min each time. The gear casting production process is simple, easy to achieve and high in production efficiency; a produced gear is good in abrasion resistance, high in tensile strength, good in expanding performance and high in shearing strength.
Description
Technical field
The present invention relates to gear technique field, be specifically related to a kind of gear casting production process.
Background technology
Gear industry obtains develop rapidly in China.Gear is the intermeshing machine components having tooth of energy, and the application of gear in transmission has occurred very early.
In machine building industry, manufacture gear material used by many kinds, there are steel, iron, copper alloy and nonmetallic materials etc., generally maximum with steel gear application, but mostly steel gear is to be manufactured by machining, and its anti-wear performance is poor, the gear of other materials, due to the advantage that respectively has some different and defect, be only applicable in the occasion of some special requirements.At present, the operation that traditional machining makes gear comprises blanking, forges, rough turn, normalizing, finish turning, gear hobbing, gear shaping, chamfering, chamfered edge and grinding out etc., traditional Gear Production operation is many, technique is more complicated, and the production cycle is long, production efficiency is low, and production cost is also higher.Gear of the prior art is made up of aluminum alloy materials mostly, and before its wearability, tension, shareholder, shear strength and extension property all have much room for improvement.The technique of present manufacture gear mostly is: stir-be shaped-sintering-packaging.In this kind of technique, a lot of company, in order to reduce cost, adopts and simplifies formula or reduce the modes such as technique, provides cost savings although simplify formula, ensures, can only use for the product of some least significant ends can lack properties of product quality.
Summary of the invention
For the deficiencies in the prior art, technical problem to be solved by this invention is, provide a kind of simple, be easy to realize, production efficiency is high, has the gear casting production process of the advantage that wearability is good, tensile strength is high, good extending performance, shear strength are high.
For solving the problems of the technologies described above, the technical solution used in the present invention is: a kind of gear casting production process, comprises the following steps:
(1) composition of raw materials: the component comprising following masses percentage: C 0.17% ~ 0.20%, Mn 3.2% ~ 4.0%, S 0.045% ~ 0.055%, P 0.04% ~ 0.05%, surplus is iron;
(2) stirred by proportioning by the composition of raw materials in step (1), Homogeneous phase mixing, drop in smelting furnace, make each raw material high-temperature fusion, melt temperature is 400-500 DEG C; Melting time is 3-6h, stirs once, stir 1-3min at every turn every 30-45min;
(3) strand: strand process adopts conticaster, and the pulling rate of described conticaster is 0.6-0.72m/min, described strand adopts M-EMS, and the electric current of described electromagnetic agitation is 400A, and frequency is 2.5Hz;
(4) sinter: raw for product embryo is put on carbon plate, in sintering furnace, sinters 3.5-4h, sintering furnace temperature-670 DEG C-1140 DEG C, sinter raw for product embryo into semi-finished product;
(5) recessing: the semi-finished product sintered are processed C catching groove footpath and O type annular groove footpath;
(6) heat treatment: the semi-finished product that car is good are placed on heat treatment guipure, are heated by heat-treatment furnace, heat treatment temperature 850 DEG C ± 10 DEG C, heat treatment time 1-3 hour, then enter oil groove quenching, oil temperature less than 60 DEG C, makes product hardness reach within the scope of HRA30-45 degree; Again the blank obtained is heated to 830-920 DEG C and carries out Carburization Treatment, and above temperature hold-time carries out Slow cooling after being no less than 3h, Carburization Treatment in Carburization Treatment, described Carburization Treatment comprises warm-up phase, surging carbon impregnation stage and the diffusion phase of successively carrying out; Described warm-up phase is blank is placed in the methyl alcohol of 830-860 DEG C and propane gas hot 20-30min altogether, the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are warming up to 875-920 DEG C and keep 2-3h by described surging carbon impregnation stage, 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 that the blank of surging carbon impregnation stage, methyl alcohol and propane gas environment temperature reduction are kept 1.5-2h to 830-880 DEG C, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
(7) polish: with deburring, burr machine, removal burr, burr are carried out to gear, and with Boring machine, Boring is carried out to gear, obtain gear finished product.
(8) oil immersion packaging: finished product is cleaned oil immersion, packaging.
Above-mentioned gear casting production process, the sintering of described step (4) is divided into six sections, the sintering furnace temperature of each section is: first paragraph 680 DEG C ± 10 DEG C, second segment 780 DEG C ± 10 DEG C, 3rd section 950 DEG C ± 10 DEG C, 4th section 1100 DEG C ± 10 DEG C, the 5th section 1130 DEG C ± 10 DEG C, the 6th section 1130 DEG C ± 10 DEG C.
Gear casting production process advantage of the present invention is:
1, gear casting production process of the present invention, is obtained by the disposable shaping of mould, Simplified flowsheet step, improves product surface quality, improves the adverse effect of former technique, decrease raw materials for production, better improves production efficiency, reduces production cost; Stable production process, reliability is strong, and the force-output shaft product quality of production is excellent, and performance indications are high.
2, gear casting production process of the present invention, technique 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 obtains refinement, gear product martensitic structure metallographic grade is 3, the gear martensitic structure metallographic grade adopting this material to obtain compared to prior art have dropped 2-3 grade, simultaneously, by above Technology for Heating Processing, the gear surface hardness obtained remains on 59-60HRC, centre hardness grade remains on 35-36HRC, and case-hardening layer thickness is 1.2-1.4mm.Above product gear parameter makes gear, and in use cementation zone not easily departs from, gear impact resistance, wearability and intensity is suitable for, service life of gear be the 6-8 of the equal gear adopting existing Technology for Heating Processing to obtain doubly.
3, gear casting production process of the present invention, its tensile strength is up to 450Mpa, and shear strength is up to 280 Mpa, and percentage elongation is greater than 8, anti-wear performance, and case hardness is 2000 ~ 2500HV, and wearability is good.Process time is short, and working (machining) efficiency is high, and production cost is low.
Detailed description of the invention
Below in conjunction with embodiment, the invention will be further described.
Embodiment 1, a kind of gear casting production process, comprises the following steps:
(1) composition of raw materials: the component comprising following masses percentage: C 0.17%%, Mn 3.2%%, S 0.045%%, P 0.04%%, surplus is iron;
(2) stirred by proportioning by the composition of raw materials in step (1), Homogeneous phase mixing, drop in smelting furnace, make each raw material high-temperature fusion, melt temperature is 400-500 DEG C; Melting time is 3-6h, stirs once, stir 1-3min at every turn every 30-45min;
(3) strand: strand process adopts conticaster, and the pulling rate of described conticaster is 0.6-0.72m/min, described strand adopts M-EMS, and the electric current of described electromagnetic agitation is 400A, and frequency is 2.5Hz;
(4) sinter: raw for product embryo is put on carbon plate, in sintering furnace, sinters 3.5-4h, sintering furnace temperature-670 DEG C-1140 DEG C, sinter raw for product embryo into semi-finished product;
(5) recessing: the semi-finished product sintered are processed C catching groove footpath and O type annular groove footpath;
(6) heat treatment: the semi-finished product that car is good are placed on heat treatment guipure, are heated by heat-treatment furnace, heat treatment temperature 850 DEG C ± 10 DEG C, heat treatment time 1-3 hour, then enter oil groove quenching, oil temperature less than 60 DEG C, makes product hardness reach within the scope of HRA30-45 degree; Again the blank obtained is heated to 830-920 DEG C and carries out Carburization Treatment, and above temperature hold-time carries out Slow cooling after being no less than 3h, Carburization Treatment in Carburization Treatment, described Carburization Treatment comprises warm-up phase, surging carbon impregnation stage and the diffusion phase of successively carrying out; Described warm-up phase is blank is placed in the methyl alcohol of 830-860 DEG C and propane gas hot 20-30min altogether, the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are warming up to 875-920 DEG C and keep 2-3h by described surging carbon impregnation stage, 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 that the blank of surging carbon impregnation stage, methyl alcohol and propane gas environment temperature reduction are kept 1.5-2h to 830-880 DEG C, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
(7) polish: with deburring, burr machine, removal burr, burr are carried out to gear, and with Boring machine, Boring is carried out to gear, obtain gear finished product.
(8) oil immersion packaging: finished product is cleaned oil immersion, packaging.
The sintering of described step (4) is divided into six sections, and the sintering furnace temperature of each section is: first paragraph 680 DEG C ± 10 DEG C, second segment 780 DEG C ± 10 DEG C, 3rd section 950 DEG C ± 10 DEG C, 4th section 1100 DEG C ± 10 DEG C, the 5th section 1130 DEG C ± 10 DEG C, the 6th section 1130 DEG C ± 10 DEG C.
Embodiment 2, a kind of gear casting production process, comprises the following steps:
(1) composition of raw materials: the component comprising following masses percentage: C 0.20%, Mn4.0%, S0.055%, P 0.05%, surplus is iron;
(2) stirred by proportioning by the composition of raw materials in step (1), Homogeneous phase mixing, drop in smelting furnace, make each raw material high-temperature fusion, melt temperature is 400-500 DEG C; Melting time is 3-6h, stirs once, stir 1-3min at every turn every 30-45min;
(3) strand: strand process adopts conticaster, and the pulling rate of described conticaster is 0.6-0.72m/min, described strand adopts M-EMS, and the electric current of described electromagnetic agitation is 400A, and frequency is 2.5Hz;
(4) sinter: raw for product embryo is put on carbon plate, in sintering furnace, sinters 3.5-4h, sintering furnace temperature-670 DEG C-1140 DEG C, sinter raw for product embryo into semi-finished product;
(5) recessing: the semi-finished product sintered are processed C catching groove footpath and O type annular groove footpath;
(6) heat treatment: the semi-finished product that car is good are placed on heat treatment guipure, are heated by heat-treatment furnace, heat treatment temperature 850 DEG C ± 10 DEG C, heat treatment time 1-3 hour, then enter oil groove quenching, oil temperature less than 60 DEG C, makes product hardness reach within the scope of HRA30-45 degree; Again the blank obtained is heated to 830-920 DEG C and carries out Carburization Treatment, and above temperature hold-time carries out Slow cooling after being no less than 3h, Carburization Treatment in Carburization Treatment, described Carburization Treatment comprises warm-up phase, surging carbon impregnation stage and the diffusion phase of successively carrying out; Described warm-up phase is blank is placed in the methyl alcohol of 830-860 DEG C and propane gas hot 20-30min altogether, the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are warming up to 875-920 DEG C and keep 2-3h by described surging carbon impregnation stage, 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 that the blank of surging carbon impregnation stage, methyl alcohol and propane gas environment temperature reduction are kept 1.5-2h to 830-880 DEG C, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%.
(7) polish: with deburring, burr machine, removal burr, burr are carried out to gear, and with Boring machine, Boring is carried out to gear, obtain gear finished product.
(8) oil immersion packaging: finished product is cleaned oil immersion, packaging.
The sintering of described step (4) is divided into six sections, and the sintering furnace temperature of each section is: first paragraph 680 DEG C ± 10 DEG C, second segment 780 DEG C ± 10 DEG C, 3rd section 950 DEG C ± 10 DEG C, 4th section 1100 DEG C ± 10 DEG C, the 5th section 1130 DEG C ± 10 DEG C, the 6th section 1130 DEG C ± 10 DEG C.
Certainly, above-mentioned explanation is not limitation of the present invention, and the present invention is also not limited to above-mentioned citing; those skilled in the art; in essential scope of the present invention, the change made, change, interpolation or replacement, all should belong to protection scope of the present invention.
Claims (2)
1. a gear casting production process, is characterized in that: comprise the following steps:
(1) composition of raw materials: the component comprising following masses percentage: C 0.17% ~ 0.20%, Mn 3.2% ~ 4.0%, S 0.045% ~ 0.055%, P 0.04% ~ 0.05%, surplus is iron;
(2) stirred by proportioning by the composition of raw materials in step (1), Homogeneous phase mixing, drop in smelting furnace, make each raw material high-temperature fusion, melt temperature is 400-500 DEG C; Melting time is 3-6h, stirs once, stir 1-3min at every turn every 30-45min;
(3) strand: strand process adopts conticaster, and the pulling rate of described conticaster is 0.6-0.72m/min, described strand adopts M-EMS, and the electric current of described electromagnetic agitation is 400A, and frequency is 2.5Hz;
(4) sinter: raw for product embryo is put on carbon plate, in sintering furnace, sinters 3.5-4h, sintering furnace temperature-670 DEG C-1140 DEG C, sinter raw for product embryo into semi-finished product;
(5) recessing: the semi-finished product sintered are processed C catching groove footpath and O type annular groove footpath;
(6) heat treatment: the semi-finished product that car is good are placed on heat treatment guipure, are heated by heat-treatment furnace, heat treatment temperature 850 DEG C ± 10 DEG C, heat treatment time 1-3 hour, then enter oil groove quenching, oil temperature less than 60 DEG C, makes product hardness reach within the scope of HRA30-45 degree; Again the blank obtained is heated to 830-920 DEG C and carries out Carburization Treatment, and above temperature hold-time carries out Slow cooling after being no less than 3h, Carburization Treatment in Carburization Treatment, described Carburization Treatment comprises warm-up phase, surging carbon impregnation stage and the diffusion phase of successively carrying out; Described warm-up phase is blank is placed in the methyl alcohol of 830-860 DEG C and propane gas hot 20-30min altogether, the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are warming up to 875-920 DEG C and keep 2-3h by described surging carbon impregnation stage, 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 that the blank of surging carbon impregnation stage, methyl alcohol and propane gas environment temperature reduction are kept 1.5-2h to 830-880 DEG C, and control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 0.7-0.75%;
(7) polish: with deburring, burr machine, removal burr, burr are carried out to gear, and with Boring machine, Boring is carried out to gear, obtain gear finished product;
(8) oil immersion packaging: finished product is cleaned oil immersion, packaging.
2. gear casting production process according to claim 1, it is characterized in that: the sintering of described step (4) is divided into six sections, the sintering furnace temperature of each section is: first paragraph 680 DEG C ± 10 DEG C, second segment 780 DEG C ± 10 DEG C, 3rd section 950 DEG C ± 10 DEG C, 4th section 1100 DEG C ± 10 DEG C, the 5th section 1130 DEG C ± 10 DEG C, the 6th section 1130 DEG C ± 10 DEG C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410678967.5A CN104439993A (en) | 2014-11-24 | 2014-11-24 | Gear casting production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410678967.5A CN104439993A (en) | 2014-11-24 | 2014-11-24 | Gear casting production process |
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| Publication Number | Publication Date |
|---|---|
| CN104439993A true CN104439993A (en) | 2015-03-25 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410678967.5A Pending CN104439993A (en) | 2014-11-24 | 2014-11-24 | Gear casting production process |
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| Country | Link |
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| CN (1) | CN104439993A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107287521A (en) * | 2017-06-28 | 2017-10-24 | 安徽华飞机械铸锻有限公司 | A kind of gear casting production process |
| CN108588553A (en) * | 2018-03-28 | 2018-09-28 | 徐州东鑫铸造有限公司 | A kind of gear casting production process |
| CN113070650A (en) * | 2021-03-18 | 2021-07-06 | 重庆市永和直锥齿有限公司 | Zero-degree arc tooth production process and gear manufacturing device |
-
2014
- 2014-11-24 CN CN201410678967.5A patent/CN104439993A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107287521A (en) * | 2017-06-28 | 2017-10-24 | 安徽华飞机械铸锻有限公司 | A kind of gear casting production process |
| CN108588553A (en) * | 2018-03-28 | 2018-09-28 | 徐州东鑫铸造有限公司 | A kind of gear casting production process |
| CN113070650A (en) * | 2021-03-18 | 2021-07-06 | 重庆市永和直锥齿有限公司 | Zero-degree arc tooth production process and gear manufacturing device |
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Application publication date: 20150325 |