CN111647843A - Composite heat treatment process for manufacturing hollow brick mold by using plate - Google Patents
Composite heat treatment process for manufacturing hollow brick mold by using plate Download PDFInfo
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- CN111647843A CN111647843A CN202010552269.6A CN202010552269A CN111647843A CN 111647843 A CN111647843 A CN 111647843A CN 202010552269 A CN202010552269 A CN 202010552269A CN 111647843 A CN111647843 A CN 111647843A
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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
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- 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
- B23P15/24—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass dies
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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
- C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
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- Organic Chemistry (AREA)
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- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
Abstract
The invention discloses a composite heat treatment process for manufacturing a hollow brick mould by using a plate, which comprises the following steps: replacing 20CrMnTi with Q235 to manufacture a hollow brick die, and carrying out heat treatment on the Q235; the specific process comprises the following steps: introducing ammonia for heat treatment: the invention relates to a method for manufacturing a steel plate, which comprises the following steps of blanking, welding forming, normalizing, mechanical rough machining, cold extrusion forming, stress relief annealing, finish machining, ammonia introduction after carburization, quenching, tempering, grinding and polishing and assembling, wherein the atmosphere of a furnace in the carburization stage in ammonia introduction heat treatment is 1.0%, ammonia gas is introduced in the cooling and diffusion stage, the atmosphere is reduced to 0.85%, the heat preservation time of carburization is 5h, and the furnace is cooled to 840 ℃ for quenching after heat preservation.
Description
Technical Field
The invention relates to the technical field of hollow brick mold composite heat treatment, in particular to a composite heat treatment process for manufacturing a hollow brick mold by using a plate.
Background
The hollow brick mold is mainly used for producing hollow bricks for buildings, factories and the like, so that the surface of the brick mold is required to have certain hardness and wear resistance, and the core of the brick mold has high toughness. The brick die length of the hollow brick adopts 20CrMnTi, and the brick die has excellent performance through round steel wire cutting molding of the 20CrMnTi and a carburizing heat treatment process;
however, 20CrMnTi belongs to alloy steel with higher price, and a large amount of steel is wasted in linear cutting forming, so that the cost is greatly increased, and the economic and practical requirements are not met.
Disclosure of Invention
The invention provides a composite heat treatment process for manufacturing a hollow brick mould by using a plate, which can effectively solve the problems that 20CrMnTi belongs to alloy steel with higher price and a large amount of steel is wasted in linear cutting forming, so that the cost is greatly increased and the economic and practical requirements are not met in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a composite heat treatment process for manufacturing a hollow brick mold by using a plate comprises the following steps: replacing 20CrMnTi with Q235 to manufacture a hollow brick die, and carrying out heat treatment on the Q235;
the specific process comprises the following steps:
introducing ammonia for heat treatment: blanking, welding and forming, normalizing, mechanical rough machining, cold extrusion forming, stress relief annealing, finish machining, ammonia introduction after carburization, quenching, tempering, grinding and polishing and assembling.
According to the technical scheme, the atmosphere of a furnace in the carburizing stage in the ammonia introduction heat treatment is 1.0%, ammonia gas is introduced in the cooling diffusion stage, the atmosphere is reduced to 0.85%, the heat preservation time of carburizing is 5h, and the furnace is cooled to 840 ℃ for quenching after heat preservation.
According to the technical scheme, the quenching heating temperature is 840 ℃, the heat preservation time is 1.5h, water cooling is carried out after heat preservation, and low-temperature tempering is carried out after quenching.
According to the technical scheme, the low-temperature tempering temperature is 200 ℃, the tempering heat preservation time is 4 hours, and air cooling is carried out after tempering.
According to the technical scheme, the ammonia is introduced for detection after heat treatment, and the detection process is as follows: the Q235 composite heat treatment workpiece is subjected to hardness and deep layer test through a microhardness tester, the surface hardness reaches 62HRC, the deep layer depth reaches 0.7mm (35HRC is a seeping layer standard), and the hardness is equivalent to that of the raw material 20CrMnTi after heat treatment.
According to the technical scheme, the wear resistance is measured on an ML-100 abrasive wear testing machine, the rotating speed of a disc is 120r/m, the feeding amount of a sample is 2mm/r, the total revolution is 180r, the size of the sample is a cylinder with the diameter of 3mm, and the specific wear amount of 20CrMnTi after carburization and the ammonia introduction amount of Q235 after carburization are measured by a weight loss method under the condition that the load is 2N;
specific abrasion loss is abrasion loss divided by original weight.
According to the technical scheme, the raw materials are ground after being welded in the welding forming process, uneven parts in the welding process are removed, and an ecological permeability test is carried out to prevent sand holes.
According to the technical scheme, the cold extrusion forming is carried out by adopting a controlled variable method, the extrusion speed is respectively 1mm/s, 2mm/s and 3mm/s, the friction coefficient is a fixed value, and the analysis result of the extrusion process is analyzed respectively when the extrusion is 20mm and 40 mm;
and the maximum extrusion force value is obviously increased along with the increase of the extrusion speed, the maximum extrusion force value occurs at the corners of the female die and the male die and at the extrusion outlet, and the farther from the points, the smaller the extrusion force is.
According to the technical scheme, the maximum equivalent plastic strain value is obviously reduced along with the increase of the extrusion speed in the cold extrusion forming, the maximum plastic strain value is generated near the extrusion outlet, and the equivalent plastic strain value is reduced as the distance from the extrusion outlet is increased;
the different speeds during cold extrusion have an effect on the distribution of the stresses, but the maximum value of the equivalent stress does not change significantly with increasing speed.
According to the technical scheme, the processing times in the finish machining are 2-3 times.
Compared with the prior art, the invention has the beneficial effects that: the invention has scientific and reasonable structure and safe and convenient use, the invention uses the common carbon steel Q235 steel plate, achieves the performance of the raw material by the composite heat treatment process after welding and forming, thus greatly reducing the cost, the abrasion loss is equivalent to about 0.36 percent after testing, and the cost is 50 percent of the principle after adopting the Q235 composite heat treatment process through cost accounting.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention.
In the drawings:
FIG. 1 is a schematic flow chart of the operation of the present invention.
Detailed Description
The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.
Example (b): as shown in FIG. 1, the invention provides a technical scheme of a composite heat treatment process for manufacturing a hollow brick mold by a plate, which comprises the following steps: replacing 20CrMnTi with Q235 to manufacture a hollow brick die, and carrying out heat treatment on the Q235;
the specific process comprises the following steps:
introducing ammonia for heat treatment: blanking, welding and forming, normalizing, mechanical rough machining, cold extrusion forming, stress relief annealing, finish machining, ammonia introduction after carburization, quenching, tempering, grinding and polishing and assembling.
According to the technical scheme, the atmosphere of a furnace in the carburizing stage in the ammonia introduction heat treatment is 1.0%, ammonia gas is introduced in the cooling diffusion stage, meanwhile, the atmosphere is reduced to 0.85%, the heat preservation time of the carburizing is 5h, and the furnace is cooled to 840 ℃ for quenching after heat preservation.
According to the technical scheme, the quenching heating temperature is 840 ℃, the heat preservation time is 1.5h, water cooling is carried out after heat preservation, and low-temperature tempering is carried out after quenching.
According to the technical scheme, the temperature of low-temperature tempering is 200 ℃, the tempering heat preservation time is 4 hours, and air cooling is carried out after tempering.
According to the technical scheme, the detection is carried out after ammonia is introduced for heat treatment, and the detection process is as follows: the Q235 composite heat treatment workpiece is subjected to hardness and deep layer test through a microhardness tester, the surface hardness reaches 62HRC, the deep layer depth reaches 0.7mm (35HRC is a seeping layer standard), and the hardness is equivalent to that of the raw material 20CrMnTi after heat treatment.
According to the technical scheme, the wear resistance is measured on an ML-100 abrasive wear testing machine, the rotating speed of a disc is 120r/m, the feeding amount of a sample is 2mm/r, the total rotating speed is 180r, the size of the sample is a cylinder with the diameter of 3mm, and the specific wear amount of 20CrMnTi after carburization and the ammonia introduction of Q235 after carburization are measured by a weight loss method under the condition that the load is 2N;
specific abrasion loss is abrasion loss divided by original weight.
According to the technical scheme, the raw materials are ground after being welded in the welding forming process, uneven parts in the welding process are removed, and an ecological permeability test is carried out to prevent sand holes.
According to the technical scheme, a controlled variable method is adopted for extrusion in cold extrusion forming, the extrusion speed is respectively 1mm/s, 2mm/s and 3mm/s, the friction coefficient is a fixed value, and the analysis result of the extrusion process is analyzed respectively when the extrusion is 20mm and 40 mm;
and the maximum extrusion force value is obviously increased along with the increase of the extrusion speed, the maximum extrusion force value occurs at the corners of the female die and the male die and at the extrusion outlet, and the farther from the points, the smaller the extrusion force is.
According to the technical scheme, the maximum equivalent plastic strain value is obviously reduced along with the increase of the extrusion speed in cold extrusion forming, the maximum plastic strain value is generated near the extrusion outlet, and the equivalent plastic strain value is reduced as the distance from the extrusion outlet is increased;
the different speeds during cold extrusion have an effect on the distribution of the stresses, but the maximum value of the equivalent stress does not change significantly with increasing speed.
According to the technical scheme, the processing times in the finish machining are 3 times.
Compared with the prior art, the invention has the beneficial effects that: the invention has scientific and reasonable structure and safe and convenient use, the invention uses the common carbon steel Q235 steel plate, achieves the performance of the raw material by the composite heat treatment process after welding and forming, thus greatly reducing the cost, the abrasion loss is equivalent to about 0.36 percent after testing, and the cost is 50 percent of the principle after adopting the Q235 composite heat treatment process through cost accounting.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The composite heat treatment process for manufacturing the hollow brick mold by the plate is characterized by comprising the following steps of: the method comprises the following steps: replacing 20CrMnTi with Q235 to manufacture a hollow brick die, and carrying out heat treatment on the Q235;
the specific process comprises the following steps:
introducing ammonia for heat treatment: blanking, welding and forming, normalizing, mechanical rough machining, cold extrusion forming, stress relief annealing, finish machining, ammonia introduction after carburization, quenching, tempering, grinding and polishing and assembling.
2. The composite heat treatment process for manufacturing the hollow brick mold by the plates as claimed in claim 1, wherein the atmosphere of the furnace in the carburizing stage in the ammonia introducing heat treatment is 1.0%, ammonia gas is introduced in the cooling diffusion stage, the atmosphere is reduced to 0.85%, the heat preservation time of the carburizing is 5h, and the furnace is cooled to 840 ℃ for quenching after the heat preservation.
3. The composite heat treatment process for manufacturing the hollow brick mold from the plate as claimed in claim 1, wherein the quenching heating temperature is 840 ℃, the heat preservation time is 1.5h, water cooling is performed after heat preservation, and low-temperature tempering is performed after quenching.
4. The composite heat treatment process for manufacturing the hollow brick mold by the plate as claimed in claim 3, wherein the low-temperature tempering temperature is 200 ℃, the tempering heat preservation time is 4 hours, and air cooling is performed after tempering.
5. The composite heat treatment process for manufacturing the hollow brick mold for the plate according to claim 1, wherein detection is performed after ammonia introduction heat treatment, and the detection process is as follows: the Q235 composite heat treatment workpiece is subjected to hardness and deep layer test through a microhardness tester, the surface hardness reaches 62HRC, the deep layer depth reaches 0.7mm (35HRC is a seeping layer standard), and the hardness is equivalent to that of the raw material 20CrMnTi after heat treatment.
6. The composite heat treatment process for manufacturing the hollow brick mold by the sheet material as claimed in claim 5, wherein the abrasion resistance is measured on an ML-100 abrasive abrasion tester, the rotating speed of a disc is 120r/m, the feeding amount of a sample is 2mm/r, the total rotating speed is 180r, the size of the sample is a cylinder with the diameter of 3mm, and the specific abrasion loss of 20CrMnTi after carburization and the ammonia introduction of Q235 after carburization are measured by a weight loss method under the condition of 2N load;
specific abrasion loss is abrasion loss divided by original weight.
7. The composite heat treatment process for manufacturing the hollow brick mold by the plates as claimed in claim 1, wherein the raw materials are ground after being welded in the welding forming process, irregularities in the welding process are removed, and an ecological permeability test is carried out to prevent sand holes.
8. The composite heat treatment process for manufacturing the hollow brick die by the sheet material as claimed in claim 1, wherein the cold extrusion forming is performed by a controlled variable method, the extrusion speed is 1mm/s, 2mm/s and 3mm/s respectively, the friction coefficient is a fixed value, and the analysis results of the extrusion process are analyzed at the extrusion speed of 20mm and the extrusion speed of 40mm respectively;
and the maximum extrusion force value is obviously increased along with the increase of the extrusion speed, the maximum extrusion force value occurs at the corners of the female die and the male die and at the extrusion outlet, and the farther from the points, the smaller the extrusion force is.
9. The composite heat treatment process for manufacturing the hollow brick mold from the sheet material as claimed in claim 8, wherein the maximum equivalent plastic strain value is obviously reduced along with the increase of the extrusion speed in the cold extrusion forming, and the maximum plastic strain value is generated near the extrusion outlet, and the equivalent plastic strain value is reduced along with the increase of the distance from the extrusion outlet;
the different speeds during cold extrusion have an effect on the distribution of the stresses, but the maximum value of the equivalent stress does not change significantly with increasing speed.
10. The composite heat treatment process for manufacturing the hollow brick die by the plates as claimed in claim 1, wherein the number of times of treatment in the finish machining is 2-3 times.
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| CN202010552269.6A CN111647843A (en) | 2020-06-17 | 2020-06-17 | Composite heat treatment process for manufacturing hollow brick mold by using plate |
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| CN202010552269.6A CN111647843A (en) | 2020-06-17 | 2020-06-17 | Composite heat treatment process for manufacturing hollow brick mold by using plate |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112725812A (en) * | 2020-12-18 | 2021-04-30 | 四川德兰航宇科技发展有限责任公司 | Preparation method for improving fatigue performance of upper anvil of hydraulic press |
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Application publication date: 20200911 |