CN107177817A - It is a kind of while improving the handling process of carbon steel corrosion stability and wearability - Google Patents

Abstract

The invention discloses a treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel, comprising the following steps: degreasing with trichlorethylene steam → cleaning with distilled water → preheating → salt bath nitriding → a salt bath oxidation treatment → Vibration polishing → first washing and drying → second salt bath oxidation treatment → second washing and drying. Through the above method, the treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel described in the present invention has a better infiltration effect, and can be used in a relatively short period of time at a lower nitriding temperature on carbon steel. A thicker, uniform and denser compound compound layer is formed on the surface of the plain steel, which enables the carbon steel to obtain extremely high surface hardness, reduces energy consumption, improves production efficiency and benefits, and can form on the surface of the compound layer The dense oxide film can significantly improve the corrosion resistance and wear resistance of carbon steel.

Description

A Treatment Process for Simultaneously Improving Corrosion Resistance and Wear Resistance of Carbon Steel

technical field

The invention relates to the technical field of chemical heat treatment technology, in particular to a treatment technology for simultaneously improving the corrosion resistance and wear resistance of carbon steel.

Background technique

A large number of outdoor carbon steel parts, such as outdoor high-voltage switches, etc., are easily rusted and thinned by the corrosion of the open environment during use; on the other hand, there are carbon steel surfaces when the switch slides up and down. Therefore, it is easy to fail early, and the service life is greatly limited.

At present, the method of surface coating (galvanizing) is usually used to improve the performance of carbon steel parts. Although this technology effectively improves the corrosion resistance of parts, it does not contribute much to wear resistance. Carbon steel parts After a certain amount of wear and tear, it is easy to wear off the chromium plating layer to expose the carbon steel substrate, and it is easy to cause environmental pollution problems, and the cost is also high.

In addition, when using the traditional salt bath composite treatment technology, there are also problems such as insufficient thickness of the surface compound layer (generally 5~15μm), loose structure and insufficient corrosion resistance. In short, the existing technology is difficult to solve the corrosion and wear problems of carbon steel parts at the same time, often due to the lack of corrosion resistance, the wear of carbon steel is accelerated, or due to the lack of wear resistance, the surface is worn and damaged. Its original excellent corrosion resistance greatly shortens the service life of carbon steel parts such as outdoor high-voltage switches.

Contents of the invention

The technical problem mainly solved by the present invention is to provide a treatment process for improving the corrosion resistance and wear resistance of carbon steel at the same time, forming a thicker, uniform and denser composite compound layer on the surface of carbon steel, so that carbon While plain steel obtains extremely high surface hardness, it can form a dense oxide film on the surface of the compound layer to improve the corrosion resistance and wear resistance of carbon steel.

In order to solve the above technical problems, a technical solution adopted by the present invention is to provide a treatment process for improving the corrosion resistance and wear resistance of carbon steel at the same time, and form a thick dense anti-corrosion and wear-resistant composite surface treatment on the surface of carbon steel. layer, including the following steps:

Step 1: Degrease with trichlorethylene steam, use trichlorethylene steam to degrease the surface of the carbon steel workpiece, and steam clean at 90°C for 2 to 3 minutes;

Step 2: Distilled water washing, use distilled water for surface cleaning, and then dry quickly;

Step 3: Preheat, keep warm at 400°C for 20-30 minutes, so that the surface of the workpiece is blue or straw yellow;

Step 4: Salt bath nitriding, use a stainless steel crucible, add salt while melting the salt, keep the height of the nitrided salt at 3/4 of the depth of the crucible, salt bath nitriding temperature 560°C~600°C, time 90~150min;

Step 5: One salt bath oxidation treatment, use a stainless steel crucible, add salt while melting the salt, keep the height of the salt at 3/4 of the depth of the crucible, salt bath oxidation temperature 410~430℃, time 40~60min;

Step 6: Vibration polishing, the mass ratio of green silicon carbide abrasive to carbon steel special polishing liquid is 25:1, and the polishing time is 15~30min, which is appropriate to just expose the metal background;

Step 7: Wash and dry once;

Step 8: Secondary salt bath oxidation treatment: use a stainless steel crucible, add salt while melting the salt, keep the height of the salt at 3/4 of the depth of the crucible, salt bath oxidation temperature 410~430°C, time 40~60min, in carbon A carbon steel surface treatment layer is obtained on the surface of the plain steel workpiece;

Step 9: Second wash and dry.

In a preferred embodiment of the present invention, the step of degreasing by trichlorethylene vapor is to put the workpiece to be treated into the trichlorethylene vapor zone of the cleaning tank, control the steam temperature at 90° C., and clean for 2 minutes.

In a preferred embodiment of the present invention, the distilled water cleaning step is to place the degreased workpiece in a water tank, rinse it with flowing distilled water to remove residues on the workpiece, and transfer to drying after cleaning. Quickly dry at 150°C in a dry box.

In a preferred embodiment of the present invention, the preheating step is to immediately transfer the cleaned workpiece to an air resistance furnace and keep it warm at 400°C for 20 minutes until the surface of the workpiece is preferably blue or straw yellow.

In a preferred embodiment of the present invention, the salt bath nitriding step is to place a clean stainless steel crucible in a well-type resistance furnace, and put the well-type resistance furnace temperature control thermocouple close to the outer wall of the crucible, and then set the furnace temperature Raise it to 600°C, then add 3/4 of the base salt to the depth of the crucible, and start to melt the base salt. After the base salt in the crucible sinks, add an appropriate amount of base salt to keep the base salt at the same height, that is, 3/4 of the crucible depth, repeating this many times until the base salt is completely melted, another thermocouple is inserted into the middle of the salt liquid, and the temperature of the salt liquid is maintained at 560°C for 4 hours without load by controlling the temperature of the resistance furnace. The temperature is 560°C~600°C, and the heat preservation time is 90~150min.

In a preferred embodiment of the present invention, the first salt bath oxidation treatment step is to place a clean stainless steel crucible in a well-type resistance furnace, and place the resistance furnace temperature control thermocouple close to the outer wall of the crucible, and then maintain the furnace temperature at 300 ℃, then add half the depth of oxide salt, keep warm until it is completely melted, then continue to add an appropriate amount of oxide salt, repeat this many times until the liquid level rises to 3/4 of the depth of the crucible, to be oxidized, the salt bath oxidation temperature is 410 ~430℃, holding time is 40~60min.

In a preferred embodiment of the present invention, the step of vibrating polishing is to pour the processed workpiece into a vibrating polishing machine with green silicon carbide abrasive and carbon steel special polishing liquid for polishing.

In a preferred embodiment of the present invention, the first cleaning and drying step and the second cleaning and drying step are to transfer the polished workpiece into a cold water tank, wipe the workpiece with gauze to remove residues, and transfer to drying after cleaning. Fast drying at 150°C in the oven.

In a preferred embodiment of the present invention, the microstructure of the carbon steel surface treatment layer includes a uniform and dense structure formed by Fe2-3N, Fe3N, Fe4N and Fe3O4 compounds.

In a preferred embodiment of the present invention, the thickness of the carbon steel surface treatment layer is 25-30 μm.

The beneficial effects of the present invention are: a treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel pointed out by the present invention has a better infiltration effect, and can be used in a relatively short period of time at a lower nitrogen The heating temperature forms a thicker, uniform and denser composite compound layer on the surface of carbon steel, which enables carbon steel to obtain extremely high surface hardness, reduces energy consumption, improves production efficiency and benefits, and can be used in A dense oxide film (an oxide film formed by Fe3O4, Fe2-3N, Fe3N and Fe4N) is formed on the surface of the compound layer, which is uniform in color and beautiful in shape, and can significantly improve the corrosion resistance of carbon steel (corrosion occurs in neutral salt spray test) Time can reach more than 350h) and wear resistance.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work, wherein:

Fig. 1 is a performance index of a preferred embodiment of a treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel in the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1, the embodiment of the present invention comprises:

For the production of the nitride salt bath, place a clean stainless steel crucible in a well-type resistance furnace, and attach the temperature-controlling thermocouple of the well-type resistance furnace to the outer wall of the crucible, then raise the furnace temperature to 600°C, and then add 3/4 The base salt at the depth of the crucible begins to melt the base salt. After the base salt sinks in the crucible, add an appropriate amount of base salt to keep the base salt at the same height, which is 3/4 of the crucible depth. Repeat this many times until the base salt is completely Melt, insert another thermocouple into the middle of the salt solution, and maintain the temperature of the salt solution at 560°C for 4 hours without load by controlling the temperature of the resistance furnace, and wait for nitriding in the salt bath.

For the production of the oxide salt bath, place a clean stainless steel crucible in a well-type resistance furnace, and place the resistance furnace temperature control thermocouple close to the outer wall of the crucible, then maintain the furnace temperature at 300°C, then add half the depth of oxide salt, and keep it warm until full After melting, continue to add an appropriate amount of oxide salt, and repeat this many times until the liquid level rises to 3/4 of the depth of the crucible, waiting for oxidation.

Example 1: Put the carbon steel workpiece into the steam area of the trichlorethylene cleaning tank, control the steam temperature at 90°C, clean and degrease for 2 minutes, and then rinse the degreased workpiece with flowing distilled water to remove the surface Dust and residues are immediately dried in an oven at 150°C, and the clean and dry workpiece is transferred to an air resistance furnace, preheated at 400°C for 20 minutes, so that the surface of the workpiece is blue or straw yellow, and then the preheated workpiece is immersed in the preparation In a good nitride salt bath, keep warm at 560°C for 150min, carry out a nitride salt bath, after nitriding, transfer the workpiece to an oxidation crucible, immerse in the melted oxide salt bath, hold at 410°C for 40min, and perform a salt bath oxidation For treatment, transfer the workpiece that has been oxidized in a salt bath to a vibration polishing machine that has been added with abrasives and polishing liquid in advance, vibrate and polish for 20 minutes, then transfer the polished workpiece to a cold water tank, wipe the workpiece with gauze, and remove the polishing residue Then transfer it to an oven for drying at 150°C, then immerse the clean and dry workpiece in an oxidation salt bath again, keep it at 410°C for 40 minutes, and perform a second salt bath oxidation treatment, and finally transfer the oxidized workpiece to a cold water tank, Wipe the workpiece with gauze to remove residual salt slag, and then dry it in an oven at 150°C.

Example 2: Put the carbon steel workpiece into the steam zone of the trichlorethylene cleaning tank, control the steam temperature at 90° C., and clean and remove oil for 2 minutes. Then rinse the degreased workpiece with flowing distilled water to remove surface dust and residues, then dry it in an oven at 150°C, transfer the clean and dry workpiece to an air resistance furnace, and preheat it at 400°C for 20 minutes to make the surface of the workpiece It is blue or grass yellow, then immerse the preheated workpiece in the prepared nitride salt bath, keep it at 580°C for 120min, and carry out the nitride salt bath. After nitriding, transfer the workpiece to the oxidation crucible and immerse it In the oxidized salt bath, heat at 410°C for 80 minutes, perform a salt bath oxidation treatment, transfer the workpiece that has undergone a salt bath oxidation treatment to a vibration polishing machine that has been added with abrasives and polishing liquid in advance, vibrate and polish for 15 minutes, and then polish it. Transfer the workpiece to the cold water tank, wipe the workpiece with gauze to remove the polishing residue, then transfer it to an oven for drying at 150°C, and then immerse the clean and dry workpiece in the oxide salt bath again, keep it at 410°C for 80min, and carry out secondary salt Bath oxidation treatment, finally transfer the oxidized workpiece to a cold water tank, wipe the workpiece with gauze to remove residual salt residue, and then dry it in an oven at 150°C.

Example 3: Put the carbon steel workpiece into the steam zone of the trichlorethylene cleaning tank, control the steam temperature at 90°C, clean and degrease for 2 minutes, and then rinse the degreased workpiece with flowing distilled water to remove the surface Dust and residues are immediately dried in an oven at 150°C, and the clean and dry workpiece is transferred to an air resistance furnace, preheated at 400°C for 20 minutes, so that the surface of the workpiece is blue or straw yellow, and then the preheated workpiece is immersed in the preparation In a good nitride salt bath, keep warm at 580°C for 120 minutes, carry out a salt bath oxidation, after nitriding, transfer the workpiece to an oxidation crucible, immerse in the melted oxide salt bath, hold at 420°C for 60 minutes, and perform a salt bath oxidation For treatment, transfer the workpiece that has been oxidized in a salt bath to a vibratory polishing machine that has been added with abrasives and polishing liquid in advance, vibrate and polish for 15 minutes, then transfer the polished workpiece to a cold water tank, wipe the workpiece with gauze, and remove the polishing residue Then transfer it to an oven for drying at 150°C, then immerse the clean and dry workpiece in an oxidation salt bath again, keep it at 420°C for 60 minutes, and perform a second salt bath oxidation treatment, and finally transfer the oxidized workpiece to a cold water tank, Wipe the workpiece with gauze to remove residual salt slag, and then dry it in an oven at 150°C.

Example 4: Put the carbon steel workpiece into the steam area of the trichlorethylene cleaning tank, control the steam temperature at 90°C, clean and degrease for 2 minutes, and then rinse the degreased workpiece with flowing distilled water to remove the surface Dust and residues are immediately dried in an oven at 150°C, and the clean and dry workpiece is transferred to an air resistance furnace, preheated at 400°C for 20 minutes, so that the surface of the workpiece is blue or straw yellow, and then the preheated workpiece is immersed in the preparation In a good nitride salt bath, keep warm at 600°C for 90 minutes, and carry out a salt bath oxidation. For treatment, transfer the workpiece that has been oxidized in a salt bath to a vibratory polishing machine that has been added with abrasives and polishing liquid in advance, vibrate and polish for 30 minutes, then transfer the polished workpiece to a cold water tank, wipe the workpiece with gauze, and remove the polishing residue Then transfer it to an oven for drying at 150°C, and then immerse the clean and dry workpiece in the oxidation salt bath again, keep it at 430°C for 40 minutes, and perform the second salt bath oxidation treatment. Finally, transfer the oxidized workpiece to a cold water tank, wipe the workpiece with gauze to remove residual salt residue, and then dry it in an oven at 150°C.

Example 5: Put the carbon steel workpiece into the steam area of the trichlorethylene cleaning tank, control the steam temperature at 90°C, clean and degrease for 2 minutes, and then rinse the degreased workpiece with flowing distilled water to remove the surface Dust and residues are immediately dried in an oven at 150°C, and the clean and dry workpiece is transferred to an air resistance furnace, preheated at 400°C for 20 minutes, so that the surface of the workpiece is blue or straw yellow, and then the preheated workpiece is immersed in the preparation In a good nitride salt bath, keep warm at 600°C for 90 minutes to perform a nitride salt bath. After nitriding, transfer the workpiece to an oxidation crucible, immerse in the melted oxide salt bath, and hold at 430°C for 60 minutes to perform a salt bath oxidation For treatment, transfer the workpiece that has been oxidized in a salt bath to a vibrating polishing machine that has been added with abrasives and polishing liquid in advance, vibrate and polish until the workpiece just reveals the metal background color, then transfer the polished workpiece to a cold water tank, and use Wipe the workpiece with gauze to remove the polishing residue, then dry it in an oven at 150°C, then immerse the clean and dry workpiece in the oxidation salt bath again, keep it at 430°C for 60 minutes, and carry out the second salt bath oxidation treatment, and finally the oxidized Transfer the workpiece to a cold water tank, wipe the workpiece with gauze to remove residual salt residue, and then dry it in an oven at 150°C.

In summary, the present invention points out a treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel, which can form a dense oxide film on the surface of the compound layer, and the oxide film is Fe3O4, Fe2-3N, Fe3N and Fe4N Formed from other oxides, its color is uniform and its shape is beautiful, which can significantly improve the corrosion resistance and wear resistance of carbon steel. The corrosion time in the neutral salt spray test can reach more than 350h, and it is durable.

The above descriptions are only examples of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, shall be The same reasoning is included in the patent protection scope of the present invention.

Claims (10)

1. a kind of processing technology that improves corrosion resistance and wear resistance of carbon steel simultaneously, forms thick dense anti-corrosion and wear-resisting composite surface treatment layer on carbon steel surface, it is characterized in that, comprises the following steps: Step 1: Degrease with trichlorethylene steam, use trichlorethylene steam to degrease the surface of the carbon steel workpiece, and steam clean at 90°C for 2 to 3 minutes; Step 2: Distilled water washing, use distilled water for surface cleaning, and then dry quickly; Step 3: Preheat, keep warm at 400°C for 20-30 minutes, so that the surface of the workpiece is blue or straw yellow; Step 4: Salt bath nitriding, use a stainless steel crucible, add salt while melting the salt, keep the height of the nitrided salt at 3/4 of the depth of the crucible, salt bath nitriding temperature 560°C~600°C, time 90~150min; Step 5: One salt bath oxidation treatment, use a stainless steel crucible, add salt while melting the salt, keep the height of the salt at 3/4 of the depth of the crucible, salt bath oxidation temperature 410~430℃, time 40~60min; Step 6: Vibration polishing, the mass ratio of green silicon carbide abrasive to carbon steel special polishing liquid is 25:1, and the polishing time is 15~30min, which is appropriate to just expose the metal background; Step 7: Wash and dry once; Step 8: Secondary salt bath oxidation treatment: use a stainless steel crucible, add salt while melting the salt, keep the height of the salt at 3/4 of the depth of the crucible, salt bath oxidation temperature 410~430°C, time 40~60min, in carbon A carbon steel surface treatment layer is obtained on the surface of the plain steel workpiece; Step 9: Second wash and dry. 2. according to claim 1, improve the treatment process of corrosion resistance and wear resistance of carbon steel simultaneously, it is characterized in that, described trichlorethylene vapor degreasing step is to put workpiece to be treated into cleaning tank trichlorethylene In the ethylene steam zone, the steam temperature is controlled at 90°C and cleaned for 2 minutes. 3. The process for simultaneously improving corrosion resistance and wear resistance of carbon steel according to claim 1, wherein the distilled water cleaning step is to place the degreased workpiece in a water tank, and utilize flowing distilled water Rinse it to remove the residue on the workpiece. After cleaning, transfer it to a drying box and dry it quickly at 150°C. 4. The treatment process for simultaneously improving corrosion resistance and wear resistance of carbon steel according to claim 1, wherein the preheating step is to immediately transfer the cleaned workpiece to an air resistance furnace at 400 ° C. Keep warm for 20 minutes until the surface of the workpiece is blue or straw yellow. 5. the process for improving corrosion resistance and wear resistance of carbon steel simultaneously according to claim 1, characterized in that, the salt bath nitriding step is to place a clean stainless steel crucible in a well-type resistance furnace, Put the well-type resistance furnace temperature control thermocouple close to the outer wall of the crucible, then raise the furnace temperature to 600°C, then add base salt 3/4 of the depth of the crucible, start to melt the base salt, wait for the base salt in the crucible to sink, and then Add an appropriate amount of base salt to keep the base salt at the same height, which is 3/4 of the depth of the crucible, and repeat this many times until the base salt is completely melted. Insert another thermocouple into the middle of the salt solution and control the temperature of the resistance furnace to make The temperature of the salt solution is maintained at 560°C for 4 hours without load, and the nitriding temperature is 560°C~600°C, and the temperature is kept for 90~150min. 6. according to claim 1, improve the treatment process of corrosion resistance and wear resistance of carbon steel simultaneously, it is characterized in that, described once salt bath oxidation treatment step is to place the stainless steel crucible of cleaning into well-type electric resistance furnace, Put the resistance furnace temperature control thermocouple close to the outer wall of the crucible, then maintain the furnace temperature at 300°C, then add half the depth of oxide salt, keep warm until it is completely melted, and then continue to add an appropriate amount of oxide salt, repeat this many times until the liquid level rises As high as 3/4 of the depth of the crucible, to be oxidized, the salt bath oxidation temperature is 410~430°C, and the holding time is 40~60min. 7. The treatment process for simultaneously improving corrosion resistance and wear resistance of carbon steel according to claim 1, characterized in that, the vibration polishing step is to pour the processed workpiece into the green silicon carbide abrasive and carbon Polishing is carried out in a vibration polishing machine with a special polishing liquid for plain steel. 8. The process for improving the corrosion resistance and wear resistance of carbon steel simultaneously according to claim 1, characterized in that, the first cleaning and drying step and the secondary cleaning and drying step are to transfer the polished workpiece to a cold In the sink, wipe the workpiece with gauze to remove residues, and after cleaning, transfer it to a drying oven for rapid drying at 150°C. 9. The treatment process for simultaneously improving corrosion resistance and wear resistance of carbon steel according to claim 1, wherein the microstructure of the surface treatment layer of carbon steel comprises Fe2-3N, Fe3N, Fe4N and Fe3O4 The uniform and relatively dense structure formed by the compound. 10. The treatment process for simultaneously improving the corrosion resistance and wear resistance of carbon steel according to claim 1, wherein the thickness of the surface treatment layer of the carbon steel is 25-30 μm.