CN103194721A - Rapid QPQ (Quench-Polish-Quench) treatment method of application electric field and equipment thereof - Google Patents
Rapid QPQ (Quench-Polish-Quench) treatment method of application electric field and equipment thereof Download PDFInfo
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- CN103194721A CN103194721A CN2013101535358A CN201310153535A CN103194721A CN 103194721 A CN103194721 A CN 103194721A CN 2013101535358 A CN2013101535358 A CN 2013101535358A CN 201310153535 A CN201310153535 A CN 201310153535A CN 103194721 A CN103194721 A CN 103194721A
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Abstract
The invention relates to a metal surface chemical thermal treatment process and equipment, and in particular relates to a rapid QPQ (Quench-Polish-Quench) treatment method and equipment thereof for improving the surface property of a metal by adding a direct current electric field. The method comprises the following steps of: taking a profiling plate electrode which is arranged parallel to a surface (of a part) to be nitrided in a salt bath nitriding agent as the anode of the electric field, taking a metal piece to be nitrided as the cathode, putting the anode and the cathode into a pit furnace with the salt bath, heating the anode and the cathode, and at the same time applying the direct current electrode field to the metal piece to be nitrided and the anode so as to realize rapid nitridation. Compared with an ordinary QPQ technique, the method can increase the nitridation speed, reduce the nitridation temperature and improve the utilization rate of the nitriding agent at different temperatures within the range of 510 DEG C to 580 DEG C. Therefore, the method can take the place of multiple processes of high-frequency quenching cemented quenching, tempering, blackening (chroming) and the like, and the strength of automobiles and industrial dies can be remarkably improved when the method is applied to the industries, so that the service lives of the automobiles and industrial dies are greatly prolonged, and the production cost is lowered.
Description
Technical field
The present invention relates to a kind of hot chemical treatment of metal surface and equipment, relate in particular to a kind of quick QPQ treatment process and equipment thereof that DC electric field improves the metallic surface performance that adds.
Background technology
The compound salt bath treatment technology of QPQ is a kind of new metallic surface thermo-chemical treatment technology, and this technology has mainly comprised salt-bath nitriding and two kinds of technologies of salt bath oxidation.At first under a certain temperature, the decomposition of nitrogenize base salt is formed activated nitrogen atom, thereby in salt bath, form the nitrogen gesture district of high density, nitrogen-atoms participates in reaction formation wear resistance, the extremely excellent compound layer of erosion resistance to the metallic surface diffusion and on the top layer, the workpiece that nitriding treatment is crossed is put in people's oxidation salt bath and is carried out oxide treatment then, and the QPQ composite treatment technology is by the salt bath nitriding change of technique.This technology has realized the compound of nitriding operation and oxidation operation, nitride and oxide compound compound, and wear resistance and corrosion stability are compound, heat treatment technics and aseptic technic compound.
At present, aspect surface modification, have than multi-method such as ionitriding, tufftride, surface spraying and QPQ salt bath composite treatment technology etc., these surface modifying methods respectively have relative merits.Though ion nitriding has thicker infiltration layer, ionitriding processing cost height; When nitriding is carried out in the part mixing shove charge of handling different shapes, size and material, be difficult to make the workpiece temperature uniformity.
QPQ salt bath composite treatment technology then has little, the fabulous solidity to corrosion of distortion, good wear resistance, nuisanceless, with low cost, Remarkable Energy Saving advantage.But traditional QPQ treatment technology infiltration layer is thinner, can not satisfy namely bear frictional wear again needs have the demand of the workpiece of good corrosion resistance.Can increase alloying layer thickness to a certain extent although improve nitriding temperature and soaking time, can make infiltration layer become loose, be unfavorable for improving its wear-resisting, solidity to corrosion on the contrary.
Summary of the invention
The objective of the invention is to overcome the shortcoming that prior art exists, a kind of metal surface modification method and equipment thereof that infiltration rate is fast, infiltration layer is dark that has is provided, the present invention is by the quick QPQ technology of DC electric field, by promoting the decomposition of cyanate radical, accelerate effective diffusion and the absorption of activated nitrogen atom, significantly reduce nitriding temperature, accelerate infiltration rate.The present invention applies DC electric field by employing and solves the shortcoming that prior art exists, and realize that the technical scheme of the object of the invention is: a kind of quick QPQ treatment process of electric field that applies may further comprise the steps:
1) pending specimen surface is used successively the SiC sand paper of 400# ~ 2000# polish;
2) with dehydrated alcohol or acetone pending sample is carried out the 15min ultrasonic cleaning, remove pending specimen surface greasy dirt and impurity, dry up stand-by;
3) pending sample is put into resistance furnace and carry out preoxidation 20 ~ 30min;
4) pit furnace is warming up to 450 ~ 500 ℃ and is incubated, treat that nitrogenize base salt fully melts in the crucible after, be warming up to nitriding temperature;
5) be nitriding medium with basic salt, in salt bath, place one according to the plate electrode of pending specimen configuration design, as positive pole, as negative pole, the two poles of the earth are parallel to each other with pending sample with this plate electrode, the two poles of the earth are corresponding being connected on the positive and negative electrode of an adjustable external control continuous-current plant respectively, and placing the pit furnace heated sealed of the crucible that salt bath is housed, nitriding temperature is 510 ~ 580 ℃, nitriding time 1 ~ 4 hour, after furnace temperature reaches set(ting)value, add 5～15V voltage at two interpolars.
Technique scheme, the distance 10～100mm of described positive and negative two inter-stages.
Technique scheme, described plate electrode and pending sample place the mid-way of the salt bath degree of depth.
Technique scheme, described nitriding temperature are 575 ℃, and nitriding time is 2 hours, and two inter-stage voltages are 5V, 7.5V or 15V.
Technique scheme also comprises the salt bath oxide treatment after the nitriding, and described oxidizing temperature is 300 ~ 400 ℃, and oxidization time is 20 ~ 80min.
Technique scheme, described salt bath oxidizing temperature is 370 ℃, oxidization time is 30min.
Technique scheme, described equipment comprises external control continuous-current plant and pit furnace, pit furnace is provided with bell, be provided with crucible in the pit furnace, be placed with nitriding base salt in the described crucible, heating back nitriding base salt is molten into basic salts solution, places one according to the plate electrode of pending specimen configuration design in basic salts solution, described plate electrode links to each other by the positive pole of lead with the external control continuous-current plant, and pending sample links to each other by the negative pole of lead with external control continuous-current plant 1.
Technique scheme, described lead outside is provided with porcelain tube.
After adopting technique scheme, the present invention has following positive effect:
(1) QPQ treatment process of the present invention has overcome the deficiency that traditional Q PQ relies on penetration enhancer decomposes generation activated nitrogen atom merely, rely on diffusion to be attached to the limitation of workpiece surface again, utilize the decomposition of the physical action promotion penetration enhancer of DC electric field, increase concentration and the activity of activated nitrogen atom, play the effect of oozing of urging; In thermodiffusion, utilize anodal special shape and placement location, DC electric field is also accelerated activated nitrogen atom needs orientation diffusion from nitriding face to part (negative pole), reduced the absorption of oozing chamber interior wall and the relative nitrogen-atoms of part non-working surface relatively, thereby quickening infiltration rate, reduce the QPQ salt bath Combined Processing time, reach the purpose of energy-conserving and environment-protective;
(2) QPQ treatment process of the present invention is compared with conventional QPQ technology, differing temps in 510 ~ 580 ℃ of scopes, can realize improving the utilization ratio of nitriding speed, reduction nitriding temperature, raising nitriding medium, therefore it can substitute high-frequency quenching carburizing and quenching-tempering-blackout multiple working procedures such as (chromium plating) simultaneously, be applied in the intensity that can significantly improve them in the industries such as automobile, tool and mould, thereby increase the service life significantly, reduce production costs;
(3) QPQ treatment process of the present invention can adopt low-temperature heat to obtain the nitriding depth same with conventional QPQ, thereby save energy reduces production costs, other prior art relatively, and operation is simple in the present invention;
(4) QPQ treatment facility of the present invention is simple in structure, and low cost of manufacture can be in large-scale application.
Description of drawings
Content of the present invention is easier to be expressly understood in order to make, and according to specific embodiment also by reference to the accompanying drawings, the present invention is further detailed explanation, wherein below
Fig. 1 is a kind of quick QPQ treatment process of electric field nitriding device synoptic diagram that applies;
Fig. 2 is 575 ℃ of 35 steel, 2h, nitrided case tissue under the 5V condition;
Fig. 3 is 575 ℃ of 35 steel, 2h, nitrided case tissue under the 7.5V condition;
Fig. 4 is 575 ℃ of 35 steel, 2h, nitrided case tissue under the 15V condition;
Number in the figure 1, external control continuous-current plant; 2, bell; 3, pit furnace; 4, crucible; 5, pending sample; 6, plate electrode; 7, basic salts solution; 8, porcelain tube; 9, lead.
Embodiment
The present invention carries out in homemade QPQ handles nitriding device; as shown in Figure 1; this nitriding device comprises external control continuous-current plant 1; pit furnace 3; pit furnace is provided with bell 2; be provided with crucible 4 in the pit furnace 3; be placed with nitriding base salt in the crucible 4; heating back nitriding base salt is molten into basic salts solution 7; place the plate electrode 6 according to pending sample 5 configuration designs in salt bath, this plate electrode 6 links to each other with the positive pole of external control continuous-current plant 1 by lead 9, and pending sample 5 links to each other with the negative pole of external control continuous-current plant 1 by lead 9; lead 9 outsides are provided with porcelain tube 8, and porcelain tube 8 can play a good protection to lead 9.
(embodiment 1)
A kind of quick QPQ treatment process of electric field that applies, this method may further comprise the steps:
1) use the SiC sand paper of 400# ~ 2000# to polish successively on pending sample 5 surfaces;
2) with dehydrated alcohol or acetone pending sample 5 is carried out the 15min ultrasonic cleaning, remove pending sample 5 surface and oil contaminants and impurity, dry up stand-by;
3) pending sample 5 is put into resistance furnace and carry out preoxidation 20 ~ 30min;
4) pit furnace 3 is warming up to 450 ~ 500 ℃ and is incubated, treat that nitrogenize base salt fully melt in the crucible 4 after, be warming up to nitriding temperature;
5) be nitriding medium with basic salt, in salt bath, place one according to the plate electrode 6 of pending sample 5 layman design, with this electrode as positive pole, with pending sample 5 as negative pole, the two poles of the earth are parallel to each other, plate electrode 6 and pending sample 5 distances are 10mm, the two poles of the earth are corresponding respectively just to be connected in a special DC power supply adjustable in 5～15V scope, on the negative pole, and pit furnace 3 heated sealed that place the crucible 4 that salt bath is housed to set Heating temperature be 575 ℃, after furnace temperature reaches set(ting)value, add volts DS 5V and pick up counting at two interpolars, be incubated after 2 hours and take out;
6) immerse oxidized still and carry out surperficial salt bath oxide treatment, the salt bath oxidizing temperature is 370 ℃, and oxidization time is 30min;
7) after oxidation finishes, pending sample 5 is taken out back clean surface salt deposit and water-cooled.
Test-results: the effect of extra electric field makes 35 steel obtain the nitrided case of the about 30.2 μ m of thickness, sees Fig. 2, and existing traditional nitridation process adopts identical diffusion agent formulation, and through 575 ℃, nitriding in 2 hours only obtains the nitrided case of the about 21.7 μ m of thickness.
(embodiment 2)
1) use the SiC sand paper of 400# ~ 2000# to polish successively on pending sample 5 surfaces;
2) with dehydrated alcohol or acetone pending sample 5 is carried out the 15min ultrasonic cleaning, remove pending sample 5 surface and oil contaminants and impurity, dry up stand-by;
3) pending sample 5 is put into resistance furnace and carry out preoxidation 20 ~ 30min;
4) pit furnace 3 is warming up to 450 ~ 500 ℃ and is incubated, treat that nitrogenize base salt fully melt in the crucible 4 after, be warming up to nitriding temperature;
5) be nitriding medium with basic salt, in salt bath, place one according to the plate electrode 6 of the pending specimen configuration design of desire, with this plate electrode 6 as anodal, with part as negative pole, the two poles of the earth are parallel to each other, plate electrode 6 and pending sample 5 distances are 20mm, the two poles of the earth are corresponding respectively just to be connected in a special DC power supply adjustable in 5～15V scope, on the negative pole, and pit furnace 3 heated sealed that place the crucible 4 that salt bath is housed to set Heating temperature be 575 ℃, after furnace temperature reaches set(ting)value, add volts DS 7.5V and pick up counting at two interpolars, be incubated after 2 hours and take out;
6) immerse oxidized still and carry out surperficial salt bath oxide treatment, the salt bath oxidizing temperature is 370 ℃, and oxidization time is 30min;
7) after oxidation finishes, pending sample 5 is taken out back clean surface salt deposit and water-cooled.
Test-results: the effect of extra electric field makes 35 steel obtain the nitrided case of the about 32.1 μ m of thickness, sees Fig. 3, improves 10.4um than conventional QPQ technology nitrided case as can be known, is equivalent to improve 47.9%.
(embodiment 3)
1) use the SiC sand paper of 400# ~ 2000# to polish successively on pending sample 5 surfaces;
2) with dehydrated alcohol or acetone pending sample 5 is carried out the 15min ultrasonic cleaning, remove pending sample 5 surface and oil contaminants and impurity, dry up stand-by;
3) pending sample 5 is put into resistance furnace and carry out preoxidation 20 ~ 30min;
4) pit furnace 3 is warming up to 450 ~ 500 ℃ and is incubated, treat that nitrogenize base salt fully melt in the crucible 4 after, be warming up to nitriding temperature;
5) be nitriding medium with basic salt, in salt bath, place the plate electrode 6 according to pending sample 5 configuration designs, with this electrode as positive pole, with pending sample 5 as negative pole, the two poles of the earth are parallel to each other, plate electrode 6 and pending sample 5 distances are 100mm, the two poles of the earth are corresponding respectively just to be connected in an external control continuous-current plant adjustable in 5～15V scope, on the negative pole, and pit furnace 3 heated sealed that place the crucible 4 that salt bath is housed to set Heating temperature be 575 ℃, after furnace temperature reaches set(ting)value, add volts DS 15V and pick up counting at two interpolars, be incubated after 2 hours and take out;
6) immerse oxidized still and carry out surperficial salt bath oxide treatment, the salt bath oxidizing temperature is 370 ℃, and oxidization time is 30min;
7) after oxidation finishes, pending sample 5 is taken out back clean surface salt deposit and water-cooled.
Test-results: the effect of extra electric field makes 35 steel obtain the nitrided case of the about 32 μ m of thickness, sees Fig. 4, improves 10.3um than conventional QPQ technology nitrided case as can be known, is equivalent to improve 47.5%.
Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (8)
1. one kind applies the quick QPQ treatment process of electric field, it is characterized in that: may further comprise the steps:
1) use the SiC sand paper of 400# ~ 2000# to polish successively on pending sample (5) surface;
2) with dehydrated alcohol or acetone pending sample (5) is carried out the 15min ultrasonic cleaning, remove pending sample (5) surface and oil contaminant and impurity, dry up stand-by;
3) pending sample (5) is put into resistance furnace and carry out preoxidation 20 ~ 30min;
4) pit furnace (3) is warming up to 450 ~ 500 ℃ and is incubated, treat that the interior nitrogenize base of crucible (4) salt fully melts after, be warming up to nitriding temperature;
5) be nitriding medium with basic salt, in salt bath, place the plate electrode (6) according to pending sample (5) configuration design, with this plate electrode (6) as anodal, with pending sample (5) as negative pole, the two poles of the earth are parallel to each other, the two poles of the earth are corresponding being connected on the positive and negative electrode of an adjustable external control continuous-current plant (1) respectively, and place pit furnace (3) heated sealed of the crucible (4) that salt bath is housed, nitriding temperature is 510 ~ 580 ℃, nitriding time 1 ~ 4 hour, after furnace temperature reaches set(ting)value, add 5～15V voltage at two interpolars.
2. the quick QPQ treatment process of electric field that applies according to claim 1 is characterized in that: the distance 10～100mm of described positive and negative two inter-stages.
3. the quick QPQ treatment process of electric field that applies according to claim 1, it is characterized in that: described plate electrode (6) and pending sample (5) place the mid-way of the salt bath degree of depth.
4. according to the described quick QPQ treatment process of electric field that applies of each claim of claim 1 ~ 3, it is characterized in that: described nitriding temperature is 575 ℃, and nitriding time is 2 hours, and two inter-stage voltages are 5V, 7.5V or 15V.
5. the quick QPQ treatment process of electric field that applies according to claim 4 is characterized in that: also comprise the salt bath oxide treatment after the nitriding, described oxidizing temperature is 300 ~ 400 ℃, and oxidization time is 20 ~ 80min.
6. the quick QPQ treatment process of electric field that applies according to claim 5, it is characterized in that: described salt bath oxidizing temperature is 370 ℃, oxidization time is 30min.
7. according to the described quick QPQ treatment facility of electric field that applies of each claim of claim 1 ~ 6, it is characterized in that: described equipment comprises external control continuous-current plant (1) and pit furnace (3), pit furnace is provided with bell (2), be provided with crucible (4) in the pit furnace (3), be placed with nitriding base salt in the described crucible (4), heating back nitriding base salt is molten into basic salts solution (7), in basic salts solution (7), place the plate electrode (6) according to pending sample (5) configuration design, described plate electrode (6) links to each other with the positive pole of external control continuous-current plant (1) by lead (9), and pending sample (5) links to each other with the negative pole of external control continuous-current plant 1 by lead (9).
8. the quick QPQ treatment facility of electric field that applies according to claim 7, it is characterized in that: described lead (9) outside is provided with porcelain tube (8).
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104060215A (en) * | 2014-06-18 | 2014-09-24 | 滁州市艾德模具设备有限公司 | Plastic mold surface anticorrosion treatment method |
| CN104775089A (en) * | 2015-03-12 | 2015-07-15 | 常州大学 | Rapid salt-bath nitridation method by applying magnetic field |
| CN105525255A (en) * | 2015-12-17 | 2016-04-27 | 常州大学 | Fast and efficient aluminum-silicon-nitrogen composite permeating technology for steel |
| CN111455310A (en) * | 2020-05-28 | 2020-07-28 | 湖南申亿五金标准件有限公司 | QPQ low-temperature direct-current electric field nitriding process and device |
| CN111945106A (en) * | 2020-08-20 | 2020-11-17 | 湖南申亿五金标准件有限公司 | QPQ salt bath nitriding optimization treatment method and device through laser shock peening |
| CN112501543A (en) * | 2020-11-25 | 2021-03-16 | 太仓展东汽车配件有限公司 | Novel high-precision metal mold surface treatment process for automobile sun shield |
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| CN101880851A (en) * | 2010-04-29 | 2010-11-10 | 山东科技大学 | Novel method for carrying out low-temperature surface catalysis and nitriding on alloy cast iron |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104060215A (en) * | 2014-06-18 | 2014-09-24 | 滁州市艾德模具设备有限公司 | Plastic mold surface anticorrosion treatment method |
| CN104775089A (en) * | 2015-03-12 | 2015-07-15 | 常州大学 | Rapid salt-bath nitridation method by applying magnetic field |
| CN105525255A (en) * | 2015-12-17 | 2016-04-27 | 常州大学 | Fast and efficient aluminum-silicon-nitrogen composite permeating technology for steel |
| CN111455310A (en) * | 2020-05-28 | 2020-07-28 | 湖南申亿五金标准件有限公司 | QPQ low-temperature direct-current electric field nitriding process and device |
| CN111945106A (en) * | 2020-08-20 | 2020-11-17 | 湖南申亿五金标准件有限公司 | QPQ salt bath nitriding optimization treatment method and device through laser shock peening |
| CN112501543A (en) * | 2020-11-25 | 2021-03-16 | 太仓展东汽车配件有限公司 | Novel high-precision metal mold surface treatment process for automobile sun shield |
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Application publication date: 20130710 |