KR20080095996A - Method for formation of nitrided/carburized layer on stainless steel by the application of low temperature plasma technique - Google Patents

Abstract

A method for formation of nitrided/carburized layer on stainless steel by the application of low temperature plasma technique is provided to improve he load-bearing capacity by ensuring enough thickness of stiffened layer. A method for formation of nitrided/carburized layer on stainless steel performs as follows 1) a preprocess step(S1) which pre-processes the base material and charged at the chamber; 2) a step(S2) it injects the gas for the pre-sputtering into the chamber, and where the chamber decides on the surface of the base material to the Han plasma-generating in the voltage authorization of the pressure maintenance of the temperature keeping of 300deg.C~470deg.C and 1~10Torr and 300~1000V for 50 minutes ~2 hours with pre-sputtering; 3) a carburizing step(S3) injecting the mixed gas in which the volume ratio is comprised of the H2 of 50~94%, the Ar of 5~40%, and the CH4 of 1~10% into the chamber and forms the supersaturation carbon layer into plasma-generating by the voltage authorization of the pressure maintenance of the temperature of 400~700deg.C and 1~10Torr and 400~1000V for 1~50 hours; 4) a nitrification treatment step(S4) injecting the mixed gas in which the volume ratio is comprised of the H2 of 10~85%, the Ar of 5~40%, and the N2 of 10~85% into the chamber and forms the supersaturation nitrogen layer into plasma-generating by the voltage authorization of the pressure maintenance of the temperature of 300~390deg.C and 1~10Torr and 400~1000V for 1~10 hours; 5) a formation method of the stainless steel carburization nitride layer using the low temperature plasma technique wherein the cooling step(S5) carrying the base material out is performed in the chamber after cooling the chamber to 250deg.C.

Description

Method for formation of nitrided / carburized layer on stainless steel by the application of low temperature plasma technique

1 is a flow chart showing a method of forming a stainless steel carburized nitride layer using a plasma according to the present invention.

Figure 2 is an experimental photograph showing a cross-sectional photograph of the specimen treated by the method of forming a carburized nitride layer according to the present invention and the conventional treatment method.

Figure 3 is an experimental photograph showing the surface photograph after the polarization test of the specimen treated with the method of forming a carburized nitride layer according to the present invention and the conventional treatment method and untreated specimen.

Figure 4 is a graph comparing the corrosion resistance of the specimen treated with the method of forming a carburized nitride layer according to the present invention and the conventional treatment method and the untreated specimen.

5 is a graph comparing the surface hardness of the specimen treated by the method of forming a carburized nitride layer according to the present invention and the specimen treated by the conventional treatment method.

Figure 6 is a graph comparing the analysis results by Glow Discharge Spectroscopy (GDS) of the specimen treated with the method of forming a carburized nitriding layer according to the present invention.

Figure 7 is a graph showing the results of X-ray diffraction analysis of the specimen treated with the method of forming a carburized nitride layer according to the present invention and the conventional method and untreated specimen.

8a and 8b are photographs showing surface photographs of the specimens subjected to carburization only and the specimens treated by the method of forming a carburizing nitride layer according to the present invention.

9 is a graph showing the temperature change in the chamber in the method of forming a stainless steel carburized nitride layer using a plasma according to the present invention.

10 is a simple configuration diagram of a plasma ion device used in the present invention.

** Description of reference numerals in the drawings **

H: Heater P: Specimen (stainless steel)

PS: Plasma Vp: Vacuum Pump

S1: pretreatment step S2: presputtering step

S3: Carburizing Treatment Step S4: Nitriding Treatment Step

S5: cooling stage

The present invention relates to a method for forming a stainless steel carburized nitride layer using plasma, and more particularly, to increase load-bearing capacity through securing a sufficient thickness of a hardened layer by carburizing and to increase corrosion resistance and to increase wear resistance by nitriding. In order to secure the at the same time, but to suppress the addition of precipitates to provide a high quality supersaturated hardened structure to provide a carburizing nitriding method of stainless steel using a plasma at a low temperature.

Stainless steel (stainless steel) of the metal material has a thin oxide film (Cr ₂ O ₃ ) of 20 ~ 50Å formed on the surface serves to protect the surface from corrosion. Due to such high corrosion resistance, it is used in various fields such as food, medicine, tableware, etc., but due to its low hardness characteristics, the use of automobiles, machinery, and electronic components with high demand is limited. Therefore, the surface treatment technology of stainless steel is being developed at a high speed.

Usually, the surface treatment methods include carburizing, nitriding, and the like. First, the carburizing method is one of the oldest surface hardening methods, which absorbs carbon into the base material by heating it to a high temperature while contacting a base material having a low carbon with a material composed of carbon such as charcoal and a gas containing carbon Way.

Since the nitriding method has less deformation after treatment than other heat treatment hardening methods, the nitriding method is used in all industries as a means of extending the life of mechanical parts. Nitriding refers to an operation of hardening the surface by infiltrating nitrogen into a base material.

Particularly, nitriding using plasma involves hardening treatment by injecting active ions by plasma discharge into the metal surface, while heating the vacuum reactor to a constant reaction temperature while the metal material is installed in the reactor. Nitriding gas is introduced into the furnace, and a surface of the metal material is hardened by applying a pulsed negative voltage to the metal material to generate a plasma.

Therefore, in the case of performing the surface treatment by nitriding in order to increase the wear resistance of stainless steel, it is common to increase the hardness by diffusing and penetrating nitrogen from the surface of the metal material to the inside in the temperature range of 500 ° C to 600 ° C.

However, the nitriding treatment can improve the surface hardness by forming a high hardened layer on the surface of the stainless steel as a base material, but due to the nature of the nitriding process performed at 500 ° C. or higher, CrN is deposited to form a thin and stable Cr ₂ O ₃ film on the surface. Can not. Therefore, the physical properties of the base material is lowered, which has a problem of significantly lowering the corrosion resistance. This is because of the problem of inferior corrosion resistance, which constitutes a nitriding treatment at 400 ° C. or lower, thereby ensuring corrosion resistance but inevitably efficient wear resistance and thin cured layer thickness. There was a problem that can not secure the load bearing capacity.

Meanwhile, a surface treatment apparatus using plasma for the surface treatment method described above will be described with reference to FIG. 10. Since the carburization-nitriding treatment method according to the present invention also uses the following plasma treatment system, the present invention will be replaced with the description of the apparatus.

10 is a simple configuration diagram of a plasma ion device used in the present invention.

As shown in FIG. 10, the plasma nitriding or plasma carburizing is performed by nitriding or carburizing the specimen P by passing a gas for nitriding or carburizing through a plasma generated outside the specimen P of the base metal, and centering the inside of the chamber 1. A substrate 2 having a cathode power source is installed on the substrate 2, a specimen P is provided on the substrate 2, and a heater H is installed inside the chamber.

The gas injection unit 4 is installed above the chamber 1, and a vacuum pump Vp is installed below the chamber 1 to generate plasma PS around the specimen P. In addition, the substrate 2 and the heater H are configured to supply power through the power supply 5.

Injecting a gas corresponding to carburizing or nitriding treatment into the chamber 1 and operating the heater H to increase the internal temperature, and then generate a plasma PS for a predetermined time, thereby forming the corresponding layer on the surface of the specimen P, which is the base material. To achieve.

Meanwhile, in order to secure both corrosion resistance and abrasion resistance of stainless steel, a low temptature nitrocarburizing method using a plasma treatment system may be used. Such a conventional treatment method uses a plasma surface treatment method to treat a base material. In this case, several gas components (H ₂ , Ar, N ₂ , CH _4, etc.) at the same time, and heating them together to form a surface forming layer resistant to corrosion and high hardness by plasma.

However, as shown in each of Figures 2 to 3, the surface forming layer formed by the conventional treatment method is not only difficult to ensure a sufficient thickness, but also to ensure a sufficient thickness to maintain the chamber temperature above 400 ℃ Unnecessary CrN precipitates are generated, there is a problem that the corrosion resistance is significantly reduced.

The present invention has been made to solve the conventional problems as described above, in the formation of a stainless steel carburizing nitriding layer to increase the load-bearing capacity and increase the corrosion resistance and nitriding treatment through securing the thickness of a sufficient hardened layer by carburizing treatment It is an object of the present invention to provide a method of carburizing and nitriding stainless steel using plasma in which the surface forming layer can be composed of high-quality supersaturated hardened tissue, while simultaneously securing an increase in wear resistance.

In order to achieve the above object, the present invention provides a method of continuously forming a supersaturated carbon layer and a supersaturated nitrogen layer by using austenitic stainless steel as a base material and charging the base material into a chamber using heating and plasma. Pretreatment step of pre-treating the charge into the chamber; 2) Injecting a gas for pre-sputtering into the chamber, the chamber is 50 minutes by maintaining a temperature of 300 ℃ ~ 470 ℃, maintaining a pressure of 1 ~ 10 Torr and plasma generation by applying a voltage of 300 ~ 1000V Presputtering the surface of the base material for ˜2 hours; 3) Injecting a mixed gas composed of 50 to 94% H _{2 ,} 5 to 40% Ar, and 1 to 10% CH ₄ in a volume ratio and maintaining a temperature of 400 to 700 ° C. and a pressure of 1 to 10 Torr. Carburizing treatment step of forming a supersaturated carbon layer for 1 to 50 hours by plasma generation by applying a voltage of 400 ~ 1000V; 4) Injecting a mixed gas having a volume ratio of 10 to 85% H _{2 ,} 5 to 40% Ar, and 10 to 85% N ₂ into the chamber, and maintaining a temperature of 300 to 390 ° C. and a pressure of 1 to 10 Torr. And a nitriding treatment step of forming a supersaturated nitrogen layer for 1 to 10 hours by plasma generation by applying a voltage of 400 to 1000 V; 5) It provides a method of forming a stainless steel carburized nitriding layer using a low temperature plasma technology comprising the step of cooling the chamber to 250 ℃ and then carrying out the base material from the chamber.

In addition, between the carburizing step and the nitriding step provides a method for forming a stainless steel carburized nitriding layer using a plasma, characterized in that further comprising the step of cooling the temperature of the chamber to a temperature of 300 ~ 390 ℃. .

In addition, the pre-sputtering step is a stainless steel carburized nitriding layer using a low-temperature plasma technology, characterized in that the mixed gas composed of the volume ratio of 20 to 80% H ₂ and 20% to 80% Ar is the presputtering gas. It provides a method of forming.

In addition, the carburizing step and the nitriding step each provide a method for forming a stainless steel carburizing nitriding layer using a low-temperature plasma technology, characterized in that for generating a plasma at a time point of 0.6 ~ 1 Torr before reaching the set holding pressure in the chamber. do.

In addition, each of the pre-sputtering step, carburizing step, nitriding step and cooling step is to discharge the remaining air or the remaining gas of the previous step in the chamber to achieve a pressure of 50mTorr preferentially Provided is a method of forming a stainless steel carburized nitride layer.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Therefore, in the following description of the present invention, if it is determined that the detailed description of the related known technology or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, in the case where descriptions according to the relationship between the elements of the present invention described above are overlapped, the description thereof will be omitted.

1 is a flow chart showing a method of forming a stainless steel carburized nitride layer using a plasma according to the present invention.

As shown in FIG. 1, the present invention provides a pre-sputtering step (S1) and a pre-sputtering of the base material in order to form a supersaturated carbon layer and a supersaturated nitrogen layer on a surface of stainless steel as a base material. Step S2, carburizing the base material (S3), nitriding the base material (S4) and finally cooling (S5).

The pretreatment step (S1) includes a conventional washing process as a process for removing impurities on the surface of the base material. In particular, as a more specific and preferred embodiment of the pretreatment step S1, the following pretreatment step S1 may be proposed.

First, the surface of the base material may be polished with sandpaper or the like, and the surface polished base material is preferably mirror-treated using an alumina slurry to more evenly roughen the surface. In addition, the mirror-treated base material is preferably immersed in an acetone solution to finish by ultrasonic cleaning. Next, after the surface grinding and cleaning process is completed, the base material is charged into a chamber configured in a conventional plasma ion device.

Since the plasma ion device is the same as the above description of the related art, description of the overlapping device will be omitted.

Pre-sputtering the base material (S2) is to further remove the impurities such as the oxide film on the surface of the base material by pre-sputtering the surface of the pre-treated base material, after the carburizing treatment and nitriding treatment This is to make each formation layer (persaturated carbon layer and supersaturated nitrogen layer) on the surface more stable.

Pre-sputtering is the ion bombardment effect on the surface of the base material. It strikes inert elements to drive out metal molecules and impurities, and then attaches a film to the surface to clean the surface. As the inert gas for presputtering, CO ₂ , CO, Ar, and H ₂ gases are generally made of only one or a suitable mixture thereof.

On the other hand, the pre-sputtering step (S2) proposed in the present invention injects the pre-sputtering gas (inert gas) into the chamber in which the base material after the pretreatment step is placed. At this time, the chamber is to maintain a temperature of 300 ℃ ~ 470 ℃. In particular, the pre-sputtering gas is preferably to form a mixed gas consisting of a volume ratio of 80% H ₂ and 20% Ar. The pressure in the chamber is maintained at 1 to 10 Torr.

When the presputtering gas is injected into the chamber, plasma is applied by applying a voltage of 300 to 1000 V to presputter the surface of the base material, but the advancing time is preferably 50 minutes to 2 hours.

Carburizing the pre-sputtered base material (S3) injects a gas for carburizing treatment into the chamber and generates a plasma by applying a constant voltage to the supersaturated supercarbide layer on the surface of the base material through the carburization process by the plasma. To form a carbon layer (γ _C , C-enriched layer).

Specific details of the carburization step (S3) are as follows.

Into the chamber, a mixture gas composed of 50 to 94% H _{2 ,} 5 to 40% Ar, and 1 to 10% CH ₄ is composed of carburizing gas. In addition, the temperature of the chamber is set to maintain a pressure of 1 ~ 10 Torr while maintaining the heating to 400 ~ 700 ℃.

Then, a plasma is generated by applying a voltage of 400 to 1000 V to the chamber to form a supersaturated carbon layer (γ _C , C-enriched layer) on the surface of the base material, but the progress time is made to be 1 to 50 hours. On the other hand, it is preferable to generate the plasma at a time point of 0.6 ~ 1 Torr before reaching the set holding pressure in the chamber to generate the plasma at a relatively low pressure in advance to enable efficient operation of the plasma.

Thus, the supersaturated carbon layer formed on the surface of the base material in the carburizing step (S3) is a supersaturated nitrogen layer produced in the nitriding treatment step described later with a thickness of about 25 μm, which is relatively thick by each of the above-described conditions. In comparison with the nitride layer), the load carrying capacity is increased. In the base material stainless steel, the supersaturated carbon layer, which is the carburized layer, has a relatively low surface hardness but has high corrosion resistance.

On the other hand, the chamber temperature change of each of the carburization step (S3) and the subsequent nitriding step (S4) is about 100 ~ 300 ℃ lowered. Accordingly, after the carburizing step S3 is completed, the chamber is cooled down to a set temperature of 300 to 390 ° C. in the nitriding step S4, which is a subsequent step in which the remaining gas in the chamber is discharged to maintain the chamber in a vacuum state. It is preferable to make it.

Nitriding the presputtered base material (S4) injects a nitriding treatment gas into the chamber and applies a constant voltage to generate a plasma, thereby supersaturating a nitride layer on the surface of the base material through nitriding by the plasma. Form a nitrogen layer (γ _N , N-enriched layer). Specific details of the nitriding treatment step S4 are as follows.

Into the chamber, a mixture gas composed of 10 to 85% H _{2 ,} 5 to 40% Ar, and 10 to 85% N ₂ is composed of a nitriding gas. In addition, the temperature of the chamber is set to maintain a pressure of 1 ~ 10 Torr and maintained by heating to 300 ~ 390 ℃.

In addition, a plasma is generated by applying a voltage of 400 to 1000 V to the chamber to form a supersaturated nitrogen layer on the surface of the base material, but the progress time is made to be 1 to 10 hours. In addition, it is preferable to generate the plasma at a time point of 0.6 to 1 Torr before reaching the set holding pressure in the chamber so that the plasma can be generated in advance at a relatively low pressure to enable efficient operation of the plasma.

At this time, in the nitriding treatment step (S4), it is important to maintain the maximum temperature of nitriding at 390 ° C. to prevent the precipitation of CrN. As such, the supersaturated nitrogen layer, which is a supersaturated hardened tissue produced without the formation of CrN precipitates at low temperatures, is also referred to as supersaturated or expanded austenite (γ _N ).

In addition, the supersaturated nitrogen layer, which is a nitride layer formed on the surface of the base material in the nitriding treatment step (S4), is a carburizing produced in the nitriding treatment step described above with a relatively thin hardened layer (˜5 μm thickness) under each of the conditions described above. In contrast to the supersaturated carbon layer, which is the water layer). In the stainless steel of the base material (hardness 250HV _0.1 ), the supersaturated nitrogen layer is characterized by ensuring both high surface hardness (hardness 1300HV _0.01 ) and high corrosion resistance.

Thereafter, the chamber is cooled to 250 ° C., and then the formation of the carburized nitride layer (γ _C + γ _N ) is completed on the surface of the stainless steel, which is finally the base material, through the cooling step S5 of carrying out the base material from the chamber.

On the other hand, each of the pre-sputtering step (S2), carburizing step (S3), nitriding step (S4) and cooling step (S5), each of the air remaining in the chamber or the remaining gas of the previous step is first discharged to a pressure of 50mTorr In order to achieve this, the gas injected in the subsequent step (pre-sputtering gas, carburizing gas, nitriding gas) is prevented from changing the component ratio by the remaining gas, which is to form high quality surface layers as a result.

Hereinafter, the hardness of the specimen and the corrosion characteristics of the specimen and the carburized nitride layer formed on the surface of the stainless steel according to an embodiment of the present invention with reference to the experimental results are as follows.

Hereinafter, the stainless steel used used a disk-shaped specimen of AISI304L and the detailed configuration of one embodiment is as follows.

1) Charge the specimen into the chamber according to the pretreatment step (S1) described above.

2) Injecting a mixed gas having a volume ratio of 80% H ₂ and 20% Ar into the chamber as a pre-sputtering step (S2) and maintaining plasma at a temperature of 300 ° C. to 470 ° C. and generating a plasma by applying a voltage of 400V. Presputter the surface of the specimen (base) for 60 minutes.

3) Injecting a mixed gas composed of 75% H _{2 ,} 20% Ar, 5% CH ₄ into the chamber by carburizing step (S3), maintaining a temperature of 470 ° C. and a pressure of 4 Torr, and Plasma generation by voltage application forms a supersaturated carbon layer for 25 hours.

4) As a nitriding step (S4) _, a mixed gas having a volume ratio of 65% H _{2 ,} 10% Ar, 25% N ₂ is injected into the chamber, and the temperature is maintained at 370 ° C. and the pressure of 2 Torr and 600V The plasma generation by voltage application forms a supersaturated nitrogen layer for 5 hours.

5) Cool the chamber to 250 ° C by the cooling step (S5) and then take out the base material from the chamber. In addition, between the carburization step (S3) and the nitriding step (S4) to further include the step of cooling the temperature of the chamber to a temperature of 370 ℃.

On the other hand, the conventional treatment method is a variety of gas components (H ₂ , configured in the supersaturated carbon layer and supersaturated nitrogen layer as described in the prior art) Ar, N ₂ , CH ₄ Etc.) and all of them at the same time refers to a method of heating (chamber temperature 400 ℃ and 40 hours).

2 is an experimental photograph showing a cross-sectional photograph of a specimen treated by the method of forming a carburized nitride layer according to the present invention and a specimen treated by a conventional treatment method, and FIG. 3 is treated by the method of forming a carburized nitride layer according to the present invention. This is an experimental photograph showing the surface photograph after the polarization test of the specimen, the existing treatment method and the untreated specimen.

Each of the specimens shown in Figure 2 is corroded for about one minute in the aqua regia. The white part in each picture is the part with improved hardness. The specimen by the conventional treatment method can be seen that the thickness of the formed cured layer is relatively thin, and it can be seen that the Cr ₂ N precipitates are formed in the surface portion, thereby lowering the corrosion resistance.

3 shows a photograph of the surface of each specimen after the coincidence polarization test. The black and fitting corrosion seen in the untreated material is a local corrosion. Corrosion is a form of corrosion commonly found in stainless steel, which is a major cause of stress concentrations in locally damaged areas, making the material very brittle.

On the contrary, when looking at the specimen surface photograph of the treatment result according to the present invention, it can be seen that the black and round shapes as described above do not appear, which shows that the stress concentration phenomenon does not appear. On the other hand, the surface photograph of the specimen by the conventional treatment method shows a state without the advantage of stainless steel due to the loss of corrosion resistance and severe corrosion.

Figure 4 is a graph showing the corrosion resistance of the specimen treated with the method of forming a carburized nitriding layer according to the present invention and the conventional treatment method and the untreated specimen, Figure 5 is treated with the method of forming a carburized nitriding layer according to the present invention A graph plotting the surface hardness of specimens and specimens treated with conventional treatment methods.

As shown in Figure 4, it can be seen that the treatment method of the specimen according to the present invention has a higher potential and lower exchange current density value than the conventional treatment method, which is excellent in corrosion resistance. In addition, it can be seen that the corrosion resistance is significantly improved compared with the untreated material.

Figure 5 shows the distribution of the surface hardness of the specimen by each method, even if the treatment method (30 hours) according to the present invention takes a shorter overall time than the conventional treatment method (40 hours) by applying a large load due to the thick layer formed It also shows that the surface hardness does not fall. In addition, it can be seen that the 4 to 5 times improved compared to the surface hardness of the untreated specimen, the wear resistance was significantly increased.

6 is a graph comparing the analysis results by glow discharge optical spectroscopy (GDS) of the specimen treated by the method of forming a carburized nitride layer according to the present invention and the specimen treated by the conventional treatment method, It shows the distribution of C and N element concentrations from the surface to the inside.

That is, in the case of the conventional treatment method, even though the treatment time was 40 hours, the concentration of C was only diffused to about 15 μm, but the method according to the present invention showed that the treatment time was diffused to about 35 μm even with only about 30 hours. Can be.

7 is a graph showing the results of X-ray diffraction analysis of the specimen treated with the method of forming a carburized nitride layer according to the present invention, the conventional treatment method and the untreated specimen.

As can be seen from the graph, in the case of the specimen treated according to the present invention compared to the untreated material, the peak shift occurred as a whole, and almost no precipitate (Cr ₂ N) was formed, and the supersaturated carbon layer (γ _C ) peak and supersaturated. Nitrogen layer (γ _N ) peaks are mainly identified. On the contrary, in the case of the conventional treatment method, it can be confirmed that Cr ₂ N is formed. In addition, in the description of (gamma) _C (111) and (gamma) _N (200) shown in said FIG. 7, each said number shows the kind of crystal plane of the said hardened layer.

8a and 8b each shows a surface photograph of the specimen subjected to carburization only and the specimen treated by the method of forming a carburizing nitriding layer according to the present invention. As shown in FIG. It can be seen that sooting occurs a lot. However, if the nitriding treatment is performed after carburizing according to the present invention, it can be seen that the soot has an effect of remarkably reducing soot on the surface by performing a cleaning action during nitriding.

Figure 9 shows the temperature change in the chamber at all stages of the invention described above. The temperature change of the present invention according to the above-described embodiment is shown, and the temperature of the chamber is cooled in the time of transition from the carburizing step S3 to the nitriding step S4 and the cooling step S5. .

Although the above has been described above with reference to a preferred embodiment according to the present invention, the technical idea of the present invention is not limited thereto, and each component of the present invention is changed or modified within the technical scope of the present invention for achieving the same object and effect. Could be.

In the method of forming a stainless steel carburized nitride layer using plasma according to the present invention, it is possible to secure an increase in corrosion resistance by carburizing treatment, a load bearing ability through securing a sufficient hardened layer thickness, and an increase in wear resistance by nitriding treatment. The generation of precipitates is suppressed, and there is an advantage of securing a carburized nitride layer (γ _C + γ _N ), which is a good surface layer.

Claims (5)

In the method of charging the base material into the chamber using austenitic stainless steel as a base material to form a supersaturated carbon layer and a supersaturated nitrogen layer continuously by heating and plasma, 1) a pretreatment step of pretreatment of the base material to the chamber; 2) Injecting a gas for pre-sputtering into the chamber, the chamber is 50 minutes by maintaining a temperature of 300 ℃ ~ 470 ℃, maintaining a pressure of 1 ~ 10 Torr and plasma generation by applying a voltage of 300 ~ 1000V Presputtering the surface of the base material for ˜2 hours; 3) Injecting a mixed gas composed of 50 to 94% H _{2 ,} 5 to 40% Ar, and 1 to 10% CH ₄ in a volume ratio and maintaining a temperature of 400 to 700 ° C. and a pressure of 1 to 10 Torr. Carburizing treatment step of forming a supersaturated carbon layer for 1 to 50 hours by plasma generation by applying a voltage of 400 ~ 1000V; 4) Injecting a mixed gas having a volume ratio of 10 to 85% H _{2 ,} 5 to 40% Ar, and 10 to 85% N ₂ into the chamber, and maintaining a temperature of 300 to 390 ° C. and a pressure of 1 to 10 Torr. And a nitriding treatment step of forming a supersaturated nitrogen layer for 1 to 10 hours by plasma generation by applying a voltage of 400 to 1000 V; 5) A method of forming a stainless steel carburized nitriding layer using a low temperature plasma technique comprising: cooling the chamber to 250 ° C. and then removing the base material from the chamber. The method of claim 1, Between the carburizing step and the nitriding step The method of forming a stainless steel carburized nitride layer using a low temperature plasma technique, characterized in that further comprises the step of cooling the temperature of the chamber to a temperature of 300 ~ 390 ℃. The method according to claim 1 or 2, The presputtering step A method of forming a stainless steel carburized nitriding layer using a low temperature plasma technique, characterized in that the mixed gas having a volume ratio of 20 to 80% H ₂ and 20% to 80% Ar is the presputtering gas. The method of claim 3, wherein Each of the carburizing step and the nitriding step is A method of forming a stainless steel carburized nitride layer using a low temperature plasma technique, wherein the plasma is generated at a time point of reaching 0.6 to 1 Torr before reaching the set holding pressure in the chamber. The method of claim 4, wherein The presputtering step, carburizing step, nitriding step and cooling step respectively A method of forming a stainless steel carburized nitriding layer using a low temperature plasma technique, wherein the air remaining in the chamber or the gas remaining in the previous step is discharged to achieve a pressure of 50 mTorr.

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