CN111500846A - Heat treatment method of welded closed impeller - Google Patents
Heat treatment method of welded closed impeller Download PDFInfo
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- CN111500846A CN111500846A CN202010387008.3A CN202010387008A CN111500846A CN 111500846 A CN111500846 A CN 111500846A CN 202010387008 A CN202010387008 A CN 202010387008A CN 111500846 A CN111500846 A CN 111500846A
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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
- C21D9/34—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tyres; for rims
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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
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- Crystallography & Structural Chemistry (AREA)
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- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
The invention discloses a heat treatment method of a welded closed impeller, which comprises the steps of salt blasting treatment, acid pickling treatment, primary water washing, hot air drying, solid solution treatment, primary low-temperature quenching, high-temperature artificial aging, secondary water washing, secondary low-temperature quenching, low-temperature artificial aging and the like. The invention adopts high-temperature artificial aging, low-temperature artificial aging and secondary low-temperature quenching treatment, and is matched with twice cold and hot water alternate cleaning to ensure the strength and hardness requirements of the treated workpiece.
Description
Technical Field
The invention relates to the technical field of machining and processing, in particular to a heat treatment method of a welded closed impeller.
Background
The closed impeller is used as a key part of turbo machinery, such as a centrifugal machine integral impeller, a ship water jet propeller impeller and the like. The high-power air compressor is widely applied to the fields of aviation, aerospace (liquid rocket pumps), navigation, military, scientific research, precise instruments, high-precision medical equipment and the like, and the quality of the high-power air compressor directly influences the aerodynamic performance and the mechanical efficiency of the high-power air compressor.
At present, the processing modes of the closed impeller mainly include the following three types:
1. the integral casting molding is that investment casting is adopted for molding, although the process is simple and large, the material structure of the finished part is loose, the strength is poor, and the bearing capacity is low;
2. the impeller has certain limitations on the impeller structure, such as the flow channel is not too narrow, the torsional rate of the blade cannot be too large, and the like, otherwise, a cutter cannot enter, and naturally, cutting processing cannot be carried out;
3. the welding forming is a main means for processing the existing closed impeller, is less influenced by the width of the blade and the flow channel, and can weld the closed impeller with the narrowest flow channel width of 0.6 mm. The welding mode mainly adopts salt bath brazing, and the impeller welded by the mode often has certain influence on the hardness of the material, and the original hardness value of the material is difficult to ensure after welding. The hardness values of the parts after salt bath brazing in the past are all obtained by heat treatment: the method has the advantages that the quenching, tempering and aging are ensured, the processing quality of the part is difficult to control, if the quenching is easy to cause the crack or the desoldering phenomenon of the part material, in addition, the processing period of the part is long, the cost is high, and the requirement of the high-speed development of the existing military products is difficult to meet.
Disclosure of Invention
The invention aims to provide a heat treatment method of a welded closed impeller, which aims to solve the problems that the quenching easily occurs during the heat treatment of the closed impeller, so that the part material is easy to crack or has a desoldering phenomenon, the processing period is long, the processing cost is high, the hardness cannot meet the requirement, and the like.
The invention is realized by the following technical scheme:
a method of heat treating a welded shrouded impeller, the method comprising the steps of:
(1) and (3) fried salt treatment: taking out the welded aluminum alloy closed impeller workpiece from the salt bath furnace, and putting the aluminum alloy closed impeller workpiece into boiling water at 100 ℃ within 2min for salt blasting treatment, wherein the time is controlled to be 30-50 min;
(2) acid pickling treatment: washing the workpiece subjected to salt explosion treatment by using an acid solution for 20-30 min;
(3) primary water washing: alternately cleaning the acid-cleaned workpiece by adopting hot water and cold water, wherein the preferable alternate cleaning frequency is 2 times;
(4) and (3) hot air drying: drying the workpiece by hot air at the temperature of 60-80 ℃;
(5) solution treatment: preserving the heat of the workpiece at 400-420 ℃ for 2.5-3 h for solution treatment;
(6) primary low-temperature quenching: cooling the workpiece after the solution treatment to 200-230 ℃, soaking the workpiece in distilled water with the water temperature of 15-20 ℃ within 1min after the workpiece reaches the temperature, taking out the workpiece immediately, and cooling the workpiece to room temperature;
(7) high-temperature artificial aging: heating the workpiece subjected to primary low-temperature quenching to 130-145 ℃, and preserving heat for 8-9 h;
(8) and (3) secondary water washing: cooling the workpiece to room temperature, and then alternately cleaning the workpiece by adopting hot water and cold water, wherein the preferable alternate cleaning frequency is 1 time;
(9) secondary low-temperature quenching: soaking the workpiece in distilled water with the water temperature of 15-20 ℃ for 1min for one time, immediately taking out, and then cooling to room temperature;
(10) low-temperature artificial aging: heating the workpiece subjected to the secondary low-temperature quenching to 55-60 ℃, and preserving heat for 2-3 h;
(11) and (4) detecting and warehousing: and cooling the workpiece to room temperature after low-temperature artificial aging, detecting the hardness, and storing the workpiece with the hardness of more than or equal to 10HB in an oil seal mode.
Preferably, the step (3) is divided into the following steps:
(3-1) cleaning the workpiece by using distilled water at the temperature of 70 ℃ for 5-10 min;
(3-2) cleaning the workpiece by using distilled water at the temperature of 15 ℃ for 15-20 min;
(3-3) cleaning the workpiece by using distilled water at the temperature of 45 ℃ for 8-12 min;
and (3-4) cleaning the workpiece by using distilled water at the temperature of 10 ℃ for 20-25 min.
Preferably, the step (8) is divided into the following steps:
(8-1) cleaning the workpiece by using distilled water at the temperature of 60 ℃ for 40-45 min;
(8-2) cleaning the workpiece by adopting distilled water at the temperature of 18 ℃ for 60-120 min.
Preferably, in the step (5), the temperature is raised from normal temperature to 400-420 ℃ before solid solution, and the method is divided into a plurality of temperature raising stages, and specifically comprises the following steps:
(5-1) heating the workpiece from room temperature to 120-135 ℃ within 10-20 min, and keeping the temperature for 0.5-1 h;
(5-2) heating the workpiece from 120-135 ℃ to 180-190 ℃ within 3-5 min, and preserving heat for 1-1.5 h;
(5-3) heating the workpiece from 180-190 ℃ to 200-230 ℃ within 8-10 min, and preserving heat for 1-1.5 h;
(5-4) heating the workpiece to 400-420 ℃, and preserving heat for 2.5-3 h for solution treatment.
Preferably, the acid solution used in the step (2) is a hydrogen chloride solution with a concentration of 8-12%.
The beneficial effects of the invention are as follows:
compared with the prior art, the heat treatment method of the welded closed impeller provided by the invention adopts high-temperature artificial aging, low-temperature artificial aging and secondary low-temperature quenching treatment, and is matched with twice cold and hot water alternate cleaning to ensure the strength and hardness requirements of the treated workpiece.
Detailed Description
The present invention will be further described with reference to the following examples, but it should not be construed that the scope of the subject matter of the present invention is limited to the following examples, and various modifications, substitutions and alterations made based on the knowledge and conventional practices of the ordinary skill in the art without departing from the technical spirit of the present invention as described above are included in the scope of the present invention.
Example 1:
and (3) fried salt treatment: taking out the welded aluminum alloy closed impeller workpiece from the salt bath furnace, and putting the workpiece into boiling water at 100 ℃ within 2min for salt blasting treatment, wherein the time is controlled to be 50 min;
acid pickling treatment: washing the workpiece subjected to salt explosion treatment by adopting an acid solution, wherein the acid solution is a hydrogen chloride solution with the concentration of 12%, and the washing time is 30 min;
primary water washing: alternately cleaning the acid-washed workpiece for 2 times by adopting hot water and cold water, and specifically comprising the following steps: cleaning the workpiece with distilled water at 70 deg.C for 10 min; cleaning the workpiece with distilled water at 15 deg.C for 20 min; cleaning the workpiece with distilled water at 45 deg.C for 12 min; cleaning the workpiece with distilled water at 10 deg.C for 25 min;
and (3) hot air drying: drying the workpiece by hot air at the temperature of 80 ℃;
solution treatment: keeping the temperature of the workpiece at 420 ℃ for 3h for solution treatment, specifically heating the workpiece from room temperature to 135 ℃ within 20min, and keeping the temperature for 1 h; heating the workpiece from 135 ℃ to 190 ℃ within 5min, and keeping the temperature for 1.5 h; heating the workpiece from 190 ℃ to 230 ℃ within 10min, preserving heat for 1.5h, and then heating to 420 ℃ and preserving heat for 3 h;
primary low-temperature quenching: cooling the workpiece after the solution treatment to 230 ℃, soaking the workpiece in distilled water with the water temperature of 20 ℃ for one time in 1min after the temperature is reached, taking out the workpiece immediately, and then cooling the workpiece to room temperature;
high-temperature artificial aging: heating the workpiece subjected to primary low-temperature quenching to 145 ℃, and preserving heat for 9 hours;
and (3) secondary water washing: after cooling the workpiece to room temperature, alternately cleaning the workpiece for 1 time by adopting hot water and cold water, specifically: cleaning the workpiece with distilled water at 60 deg.C for 45 min; cleaning the workpiece with 18 deg.C distilled water for 120 min;
secondary low-temperature quenching: soaking the workpiece in distilled water with the water temperature of 20 ℃ for one time within 1min, immediately taking out, and then cooling to room temperature;
low-temperature artificial aging: heating the workpiece subjected to the secondary low-temperature quenching to 60 ℃, and preserving heat for 3 hours;
and (4) detecting and warehousing: and cooling the workpiece to room temperature after low-temperature artificial aging, detecting the hardness, and storing the workpiece with the hardness of more than or equal to 10HB in an oil seal mode.
Example 2:
and (3) fried salt treatment: taking out the welded aluminum alloy closed impeller workpiece from the salt bath furnace, and putting the workpiece into boiling water at 100 ℃ within 2min for salt blasting treatment, wherein the time is controlled to be 30 min;
acid pickling treatment: washing the workpiece subjected to salt explosion treatment by adopting an acid solution, wherein the acid solution is a hydrogen chloride solution with the concentration of 8%, and the washing time is 20 min;
primary water washing: alternately cleaning the acid-washed workpiece for 2 times by adopting hot water and cold water, and specifically comprising the following steps: cleaning the workpiece with distilled water at 70 deg.C for 5 min; cleaning the workpiece with distilled water at 15 deg.C for 15 min; cleaning the workpiece with distilled water at 45 deg.C for 8 min; cleaning the workpiece with distilled water at 10 deg.C for 20 min;
and (3) hot air drying: drying the workpiece by hot air at the temperature of 60 ℃;
solution treatment: the workpiece is subjected to solution treatment for 2.5h at the temperature of 400 ℃, and the method specifically comprises the following steps: heating the workpiece from room temperature to 120 ℃ within 10min, and keeping the temperature for 0.5 h; heating the workpiece from 120 ℃ to 180 ℃ within 3min, and keeping the temperature for 1 h; heating the workpiece from 180 ℃ to 200 ℃ within 8min, preserving heat for 1h, and then raising the temperature to 400 ℃ and preserving heat for 2.5 h;
primary low-temperature quenching: cooling the workpiece after the solution treatment to 200 ℃, soaking the workpiece in distilled water with the water temperature of 15 ℃ for one time in 1min after the temperature is reached, taking out the workpiece immediately, and then cooling the workpiece to room temperature;
high-temperature artificial aging: heating the workpiece subjected to primary low-temperature quenching to 130 ℃, and preserving heat for 8 hours;
and (3) secondary water washing: after cooling the workpiece to room temperature, alternately cleaning the workpiece for 1 time by adopting hot water and cold water, specifically: cleaning the workpiece with distilled water at 60 deg.C for 40 min; cleaning the workpiece with 18 deg.C distilled water for 60 min;
secondary low-temperature quenching: soaking the workpiece in distilled water with the water temperature of 15 ℃ for 1min for one time, immediately taking out, and then cooling to room temperature;
low-temperature artificial aging: heating the workpiece subjected to the secondary low-temperature quenching to 55 ℃, and preserving heat for 2 hours;
and (4) detecting and warehousing: and cooling the workpiece to room temperature after low-temperature artificial aging, detecting the hardness, and storing the workpiece with the hardness of more than or equal to 10HB in an oil seal mode.
Example 3:
and (3) fried salt treatment: taking out the welded aluminum alloy closed impeller workpiece from the salt bath furnace, and putting the workpiece into boiling water at 100 ℃ within 2min for salt blasting treatment, wherein the time is controlled to be 40 min;
acid pickling treatment: washing the workpiece subjected to salt explosion treatment by adopting an acid solution, wherein the acid solution is a hydrogen chloride solution with the concentration of 10%, and the washing time is 25 min;
primary water washing: alternately cleaning the acid-washed workpiece for 2 times by adopting hot water and cold water, and specifically comprising the following steps: cleaning the workpiece with distilled water at 70 deg.C for 6 min; cleaning the workpiece with 15 deg.C distilled water for 17 min; cleaning the workpiece with distilled water at 45 deg.C for 10 min; cleaning the workpiece with distilled water at 10 deg.C for 23 min;
and (3) hot air drying: drying the workpiece by hot air at the temperature of 70 ℃;
solution treatment: the workpiece is subjected to solution treatment for 2.8 hours at the temperature of 410 ℃, and the method specifically comprises the following steps: heating the workpiece from room temperature to 130 ℃ within 15min, and keeping the temperature for 0.6 h; heating the workpiece from 125 ℃ to 188 ℃ within 4min, and keeping the temperature for 1.2 h; heating the workpiece from 184 ℃ to 220 ℃ within 8.5min, preserving heat for 1.4h, and then preserving heat for 2.8h when the temperature is raised to 410 ℃;
primary low-temperature quenching: cooling the workpiece after the solution treatment to 210 ℃, soaking the workpiece in distilled water with the water temperature of 18 ℃ for one time in 1min after the temperature is reached, taking out the workpiece immediately, and then cooling the workpiece to room temperature;
high-temperature artificial aging: heating the workpiece subjected to primary low-temperature quenching to 140 ℃, and preserving heat for 8.5 hours;
and (3) secondary water washing: after cooling the workpiece to room temperature, alternately cleaning the workpiece for 1 time by adopting hot water and cold water, specifically: cleaning the workpiece with distilled water at 60 deg.C for 42 min; cleaning the workpiece with 18 deg.C distilled water for 90 min;
secondary low-temperature quenching: soaking the workpiece in distilled water with the water temperature of 17 ℃ for 1min for one time, immediately taking out, and then cooling to room temperature;
low-temperature artificial aging: heating the workpiece subjected to the secondary low-temperature quenching to 58 ℃, and preserving heat for 2.5 hours;
and (4) detecting and warehousing: and cooling the workpiece to room temperature after low-temperature artificial aging, detecting the hardness, and storing the workpiece with the hardness of more than or equal to 10HB in an oil seal mode.
The above is the working principle and structural characteristics of this embodiment, and all such devices manufactured according to this structural scheme belong to the protection scope of the present invention.
Claims (5)
1. A heat treatment method of a welded closed impeller is characterized in that: the method comprises the following steps:
(1) and (3) fried salt treatment: taking out the welded aluminum alloy closed impeller workpiece from the salt bath furnace, and putting the aluminum alloy closed impeller workpiece into boiling water at 100 ℃ within 2min for salt blasting treatment, wherein the time is controlled to be 30-50 min;
(2) acid pickling treatment: washing the workpiece subjected to salt explosion treatment by using an acid solution for 20-30 min;
(3) primary water washing: alternately cleaning the pickled workpiece by hot water and cold water;
(4) and (3) hot air drying: drying the workpiece by hot air at the temperature of 60-80 ℃;
(5) solution treatment: preserving the heat of the workpiece at 400-420 ℃ for 2.5-3 h for solution treatment;
(6) primary low-temperature quenching: cooling the workpiece subjected to the solution treatment to 200-230 ℃, soaking the workpiece in distilled water with the water temperature of 15-20 ℃ within 1min after the workpiece reaches the temperature, taking out the workpiece immediately, and cooling the workpiece to room temperature;
(7) high-temperature artificial aging: heating the workpiece subjected to primary low-temperature quenching to 130-145 ℃, and preserving heat for 8-9 hours;
(8) and (3) secondary water washing: cooling the workpiece to room temperature, and then alternately cleaning the workpiece by using hot water and cold water;
(9) secondary low-temperature quenching: soaking the workpiece in distilled water with the water temperature of 15-20 ℃ for 1min for one time, immediately taking out, and then cooling to room temperature;
(10) low-temperature artificial aging: heating the workpiece subjected to the secondary low-temperature quenching to 55-60 ℃, and preserving heat for 2-3 hours;
(11) and (4) detecting and warehousing: and cooling the workpiece to room temperature after low-temperature artificial aging, detecting the hardness, and storing the workpiece with the hardness of more than or equal to 10HB in an oil seal mode.
2. The heat treatment method of a welded shrouded impeller according to claim 1 wherein: the step (3) is divided into the following steps:
(3-1) cleaning the workpiece by using distilled water at the temperature of 70 ℃ for 5-10 min;
(3-2) cleaning the workpiece by using distilled water at the temperature of 15 ℃ for 15-20 min;
(3-3) cleaning the workpiece by using distilled water at the temperature of 45 ℃ for 8-12 min;
and (3-4) cleaning the workpiece by using distilled water at the temperature of 10 ℃ for 20-25 min.
3. The heat treatment method of a welded shrouded impeller according to claim 1 wherein: the step (8) is divided into the following steps:
(8-1) cleaning the workpiece by using distilled water at the temperature of 60 ℃ for 40-45 min;
(8-2) cleaning the workpiece by adopting distilled water at the temperature of 18 ℃ for 60-120 min.
4. The heat treatment method of a welded shrouded impeller according to claim 1 wherein: the step (5) is divided into the following steps:
(5-1) heating the workpiece from room temperature to 120-135 ℃ within 10-20 min, and keeping the temperature for 0.5-1 h;
(5-2) heating the workpiece from 120-135 ℃ to 180-190 ℃ within 3-5 min, and preserving heat for 1-1.5 h;
(5-3) heating the workpiece from 180-190 ℃ to 200-230 ℃ within 8-10 min, and keeping the temperature for 1-1.5 h;
(5-4) heating the workpiece to 400-420 ℃, and preserving heat for 2.5-3 h for solution treatment.
5. The heat treatment method of a welded shrouded impeller according to claim 1 wherein: the acid solution adopted in the step (2) is a hydrogen chloride solution with the concentration of 8-12%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113151660A (en) * | 2021-03-22 | 2021-07-23 | 西安理工大学 | Two-stage aging process for improving strength of welding part of impeller of air blower |
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| BR8102605A (en) * | 1980-04-28 | 1982-01-19 | Alcan Int Ltd | PROCESS FOR THE PRODUCTION OF AN ALUMINUM ALLOY SHEET AND ALUMINUM ALLOY SHEET |
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| CN103160761A (en) * | 2011-12-16 | 2013-06-19 | 贵州永红航空机械有限责任公司 | Method of guaranteeing hardness of welded closed impeller after welding |
| CN103184395A (en) * | 2013-03-21 | 2013-07-03 | 陕西飞机工业（集团）有限公司 | LY12 aluminium alloy quenching technique method |
| CN103225028A (en) * | 2013-03-15 | 2013-07-31 | 北京工业大学 | Al-Er-Zr-Si heat-resistant aluminum alloy and its heat treatment technology |
| WO2015002177A1 (en) * | 2013-07-04 | 2015-01-08 | 昭和電工株式会社 | Method for producing starting material for cutting |
-
2020
- 2020-05-09 CN CN202010387008.3A patent/CN111500846A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR8102605A (en) * | 1980-04-28 | 1982-01-19 | Alcan Int Ltd | PROCESS FOR THE PRODUCTION OF AN ALUMINUM ALLOY SHEET AND ALUMINUM ALLOY SHEET |
| CN101148744A (en) * | 2007-11-05 | 2008-03-26 | 上海交大南洋机电科技有限公司 | Heat treatment technique for major diameter aluminum casting alloy hydraulic coupler impeller |
| CN103160761A (en) * | 2011-12-16 | 2013-06-19 | 贵州永红航空机械有限责任公司 | Method of guaranteeing hardness of welded closed impeller after welding |
| CN103225028A (en) * | 2013-03-15 | 2013-07-31 | 北京工业大学 | Al-Er-Zr-Si heat-resistant aluminum alloy and its heat treatment technology |
| CN103184395A (en) * | 2013-03-21 | 2013-07-03 | 陕西飞机工业（集团）有限公司 | LY12 aluminium alloy quenching technique method |
| WO2015002177A1 (en) * | 2013-07-04 | 2015-01-08 | 昭和電工株式会社 | Method for producing starting material for cutting |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113151660A (en) * | 2021-03-22 | 2021-07-23 | 西安理工大学 | Two-stage aging process for improving strength of welding part of impeller of air blower |
| CN113151660B (en) * | 2021-03-22 | 2023-02-03 | 西安理工大学 | Two-stage aging process for improving strength of welding part of impeller of air blower |
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