JP2009256748A - Fe-BASED ALLOY-MADE CLIP AND METHOD FOR MANUFACTURING THE SAME - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an Fe-based alloy-made clip which hardly rusts despite repetitive use at a high temperature and is excellent in corrosion resistance (rust-prevention), and to provide a method for manufacturing the same. <P>SOLUTION: The Fe-based alloy-made clip comprises an Fe-based alloy containing, by mass%, 0.01 to 0.10% C, 20.0 to 35.0% Ni. 10.0 to 20.0% Cr, 0.05 to 5.0% Mo, 0.10 to 1.0% V, 0.05 to 3.0% Al, 1.5 to 4.0% Ti, 0.001 to 0.010% B, ≤1.0% Si, ≤2.0% Mn, and the balance Fe with inevitable impurities, wherein the Cr concentration from at least 0.1 μm to 1 μm of the depth from the surface of the clip is ≥80% of the matrix. For example, the Fe-based alloy-made clip can be obtained by a manufacturing method using the non-oxidizing and non-nitriding atmosphere in the temperature range of at least ≥450°C in heat treatment after plastic working of a metal sheet comprising the Fe-based alloy to a clip shape. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an Fe-based alloy clip for fixing and holding a member to be heated and a method for manufacturing the same.

For example, in the case of manufacturing an image display device such as a plasma display panel (hereinafter referred to as PDP), there is a step of heating and sealing by superposing a first glass plate and a second glass plate. At this time, in order to fix and hold the first glass plate and the second glass plate (heated member) that are overlapped with each other, a pinch-type clip is used for pressing in the overlapping direction.
As this clip, for example, as proposed in Patent Documents 1 and 2, Ni-based heat-resistant alloys such as Inconel (R) 718 alloy, X-750 alloy and Ni-Cr alloy are used. However, a Ni-based heat-resistant alloy clip is very expensive because it contains a large amount of Ni, and it is not easy to perform high-precision cold processing in the form of a clip.

Therefore, the applicant of the present application is an expensive Ni-based alloy made of Fe-based alloy having intermetallic compound particles having an average particle diameter of 100 nm or less, which is dispersed in a metal structure, including one or two of Mo and W. An inexpensive clip having characteristics equivalent to or better than a manufactured clip was proposed in Patent Document 3.
JP 2004-55488 A (see column [0014]) Japanese Patent Laid-Open No. 11-190311 (see column [0010]) JP 2006-242320 A

The above-described Fe-based alloy clip proposed by the applicant of the present application is excellent in heat resistance and high in elasticity, and sufficiently satisfies various characteristics required for the clip. However, the surface of the clip rusted while repeating the fixing and holding of the member to be heated, and rust adhered to the surface of the member to be heated, which sometimes deteriorated the surface quality.
An object of the present invention is to provide a clip made of an Fe-based alloy that hardly rusts even when used repeatedly at high temperatures and has excellent corrosion resistance (rust prevention) and a method for producing the same.

  The present invention has been made in view of the above-described problems. That is, in the present invention, C: 0.01-0.10%, Ni: 20.0-35.0%, Cr: 10.0-20.0%, Mo: 0.05-5. 0%, V: 0.10 to 1.0%, Al: 0.05 to 3.0%, Ti: 1.5 to 4.0%, B: 0.001 to 0.010%, Si: 1 0.0% or less, Mn: 2.0% or less, and the balance is a clip made of an Fe-based alloy containing Fe and inevitable impurities, and a Cr concentration of at least a depth of 0.1 μm to 1 μm on the surface of the clip. It is a clip made of Fe-based alloy that is 80% or more of the phase.

The clip of the present invention is manufactured by, for example, making the atmosphere in a temperature range of at least 450 ° C. at least 450 ° C. non-oxidizing and non-nitriding in the heat treatment after plastic processing the metal plate made of the above-described Fe-based alloy into a clip shape. It can be obtained by applying the method.
Desirably, hydrogen gas, rare gas, or hydrogen gas and rare gas are introduced into the heat treatment furnace in a temperature range of at least 450 ° C. in the heat treatment.
Desirably, the heat treatment includes an aging step of heating to 600 to 800 ° C., and nitrogen gas serving as a cooling medium is introduced into the heat treatment furnace in a temperature range of 450 ° C. or lower in the final cooling of the aging step. It is.

  The clip made of Fe-based alloy according to the present invention is an inexpensive Fe-based alloy and has excellent rust prevention (corrosion resistance). Therefore, it does not easily rust even when used repeatedly at high temperatures. The surface quality of the heating member can be maintained, and it is effective for stabilizing the quality of an image display device manufactured by fixing and holding a glass such as PDP.

  As described above, an important feature of the present invention is that the Cr concentration at least 0.1 μm to 1 μm deep on the surface of the clip is 80% or more of the parent phase. That the Cr concentration is 80% or more of the parent phase means that there is no significant Cr deficiency region where the Cr concentration is less than 20% of the parent phase.

  In the above-described conventional clip made of Fe-based alloy containing a large amount of Cr, an aging treatment is applied to form a metal plate or the like into a clip shape and then to provide spring properties as a clip force source. After this aging treatment, a compound containing a large amount of Cr is generated on the surface side of the clip as a Cr-concentrated region, whereby the Cr concentration is at least 1 μm deep from the surface following the Cr-concentrated region. A Cr-deficient region in which the amount of Cr was significantly reduced to be less than 80% of the matrix was generated. Because of the clip having such a Cr-deficient region, the Cr-dense region on the surface side of the clip is worn away during repeated use at a high temperature, so that the Cr-deficient region described above is exposed to the surface of the clip, and the exposed Cr-deficient region. The area became the starting point of rusting, and the clip was rusted.

  Therefore, the clip of the present invention has a Cr-deficient region in which the Cr concentration at least 0.1 μm to 1 μm at the depth of the clip surface is 80% or more of the parent phase, and the Cr amount is significantly reduced as described above. Make it not exist. Therefore, the Fe-based alloy clip of the present invention, which does not have a Cr-deficient region that existed in conventional Fe-based alloy clips, is a Cr-deficient region in which the amount of Cr markedly decreases as a starting point of rusting. Since it does not have such a metal structure, it does not rust even if the surface of the clip is worn out during repeated use at high temperatures. In defining the Cr concentration, the reason why the depth is at least 0.1 μm from the surface of the clip is that when the Cr amount is measured, if the depth from the surface is less than 0.1 μm, an accurate measured value cannot be obtained. It is. On the other hand, the reason why the depth is set to 1 μm as the upper limit value is that when considering the rusting mechanism on the clip surface, the structure of the metal structure on the extreme surface from the clip surface to the depth of 1 μm is considered important.

The Fe-based alloy clip of the present invention will be described with reference to a specific example.
FIG. 1 is a schematic view schematically showing an example of an Fe-based alloy clip of the present invention. The clip 1 is made of a metal plate made of an Fe-based alloy, and can have a bottom part 2, a first side part 3 and a second side part 4 extending from both ends of the bottom part. The first side surface portion 3 and the second side surface portion 4 are close to each other by an elastic force. For example, when manufacturing a PDP, a glass plate that is a member to be heated can be sandwiched and held. Moreover, in the clip 1, the clamp part 5 can also be formed so that the contact area with the said glass plate may be increased near the front-end | tip of the 1st side part 3 and the 2nd side part 4. As shown in FIG.

  The Fe-based alloy clip of the present invention is made of an Fe-based alloy as described above. The Fe-based alloy is C: 0.01-0.10%, Ni: 20.0-35.0%, Cr: 10.0-20.0%, Mo: 0.05-5. 0%, V: 0.10 to 1.0%, Al: 0.05 to 3.0%, Ti: 1.5 to 4.0%, B: 0.001 to 0.010%, Si: 1 0.0% or less, Mn: 2.0% or less, and the balance contains Fe and inevitable impurities.

In the present invention, an alloy in which an appropriate amount of each additive element is added and the balance is adjusted with Fe is referred to as an Fe-based alloy, and the reason why each chemical composition is defined in the following ranges is as follows. Unless otherwise specified, the mass% is indicated.
In the present invention, C: 0.01 to 0.10%. C (carbon) has the effect of improving the strength at normal temperature and high temperature by producing Ti and V and MC type carbides and refining the crystal grains, so it is necessary to add a small amount. However, if added in excess of 0.10%, coarse MC type carbides are formed and ductility is lowered, or the amount of Ti required for age hardening is reduced. Therefore, C is set to 0.10% or less. Further, if the above-mentioned defects of C are further taken into consideration, C: 0.01 to 0.08% is preferable.

  In the present invention, Ni: 20.0 to 35.0%. NI (nickel) is an essential element for stabilizing the austenite phase of the base of the alloy. Moreover, since it is also a constituent element of the γ 'phase that is an aging precipitation phase, it is an important element for increasing the normal temperature and high temperature strength. When Ni is less than 20.0%, not only the austenite phase becomes unstable, but also the precipitation of the γ 'phase becomes insufficient, and the normal temperature and high temperature strength are lowered. Therefore, the lower limit of Ni is set to 20%. On the other hand, if Ni exceeds 35.0%, not only is it difficult to perform high-precision processing in the cold in the shape of the clip, it is difficult to obtain a further improvement effect of the characteristics of the clip of the present invention, Since the price is significantly increased, the upper limit of Ni is set to 35.0%. A preferable range of Ni is preferably 20.0 to 30.0% in order to obtain strength at higher temperatures, considering the balance between price and characteristics, and preferably 25.0 to 30.0%. It may be a range. Moreover, as a range which can improve an intensity | strength, you may exist in 30.0-35% of range.

  In the present invention, the effect obtained by adding an appropriate amount of Cr (chromium) is important, and Cr is set to 10.0 to 20.0%. Cr is an element necessary for maintaining the oxidation resistance of the clip of the present invention. When Cr is less than 10.0%, the oxidation resistance necessary for the clip of the present invention cannot be obtained. On the other hand, if Cr exceeds 20.0%, the austenite phase of the base of the alloy becomes unstable, and harmful brittle phases such as α 'phase and σ phase are generated during long-term use, and the strength and ductility of the clip are increased. Reduce. Therefore, Cr was made 10.0 to 20.0%. For example, when Mo is included in an amount of 3.0% or more, the upper limit of Cr may be 17.0% or less, and further may be 15.0% or less.

  In the present invention, Mo: 0.05 to 5.0%. Mo (molybdenum) is an element effective in increasing the normal temperature and high temperature strength by solid solution strengthening in the austenite phase in the Fe-based alloy used in the clip of the present invention. In particular, it is a necessary and important element because it provides an effect of suppressing deformation at a high temperature by the interaction with dislocation during use of the clip. When Mo is less than 0.05%, the high-temperature strength improvement effect decreases. On the other hand, when Mo exceeds 5.0%, an embrittled phase such as a Laves phase may be generated. Therefore, Mo is set to 0.05 to 5.0%. In addition, according to the intensity | strength required for a clip, the range of the preferable addition amount in the said range can be selected by balance with another additive element. For example, when Ti is contained at, for example, 3.0% or less, Mo is preferably 1.0 to 2.0%. Moreover, when Ti is contained exceeding 3.0%, for example, Mo is preferably 0.05% to 1.0%.

  In the present invention, V: 0.10 to 1.0%. V (vanadium) is added because it has the effect of refining austenite crystal grains by generating C and MC type carbides and improving the strength at room temperature and high temperature. If V is less than 0.10%, the effect of improving the strength is small. On the other hand, if V exceeds 1.0%, coarse carbides are formed and ductility is lowered, or an unstable oxide film is formed at high temperatures to prevent acid resistance. There is a possibility of harming. Therefore, V is set to 0.10 to 1.0%. Moreover, if further considering the above-mentioned defects of V, it is preferable to set V: 0.10 to 0.50%.

  In the present invention, Al: 0.05-3.0%. Al (aluminum) is one of the main constituent elements of the γ 'phase, which is an intermetallic compound that undergoes aging precipitation, and is an element necessary for increasing the normal temperature and high temperature strength. In order to contribute to strengthening by precipitating the γ 'phase, addition of 0.05% or more is necessary. On the other hand, when it exceeds 3.0%, hot workability is lowered. Therefore, Al was made 0.05 to 3.0%. In addition, Al can select suitably the preferable range within the said range in consideration of the amount of Ti which is the main element which comprises other (gamma) 'phases.

  In the present invention, Ti: 1.5 to 4.0%. Ti (titanium) is one of the main constituent elements of the γ ′ phase, which is an intermetallic compound that undergoes aging precipitation, and is an element necessary for increasing the normal temperature and high temperature strength. In order to contribute to strengthening by precipitating the γ 'phase, addition of 1.5% or more is necessary. On the other hand, when it exceeds 4.0%, it is a coarse intermetallic compound η (eta) when heated at a high temperature. ) Phase is easily formed, and the strength and ductility at high temperatures are reduced. Therefore, Ti is set to 1.5 to 4.0%. Note that Ti can be appropriately selected within a preferable range within the above range in consideration of the amount of Al as a main element constituting the other γ ′ phase.

  And the preferable combination of the amount of Al and Ti described above can be selected as appropriate, one of which is Al: 0.05 to 0.35% and Ti: 1.5 to 2.5%, Further, Al: 0.70 to 2.0% and Ti: 2.5 to 4.0%.

  In the present invention, B: 0.001 to 0.010%. B (boron), when added in a small amount, exhibits a grain boundary strengthening effect together with Ti, and is an effective element for increasing the strength and ductility at high temperatures. When B is less than 0.001%, it is difficult to obtain the above-described grain boundary strengthening effect. On the other hand, when B exceeds 0.010%, the initial melting temperature during heating is lowered and hot workability is lowered. is there. Therefore, B is set to 0.001 to 0.010%.

  In the present invention, Si and Mn are limited to Si: 1.0% or less and Mn: 2.0% or less. Si (silicon) and Mn (manganese) are added as deoxidizing elements in the alloy used in the clip of the present invention, but excessive addition may reduce high temperature strength. Therefore, Si is limited to 1.0% or less and Mn is limited to 2.0% or less. More preferably, Si is 0.5% or less and Mn is 1.5% or less.

  In the Fe-based alloy in the present invention, the balance other than the additive elements described above is Fe and inevitable impurities. Fe (iron) is necessary as an inexpensive main element of the austenite phase constituting the base in order to obtain an inexpensive alloy for the clip of the present invention. Further, since the Fe-based alloy is an alloy based on Fe, it can be said that the remainder other than the additive elements described above is substantially made of Fe, but the remainder inevitably contains impurities. For example, P (phosphorus) and S (sulfur) are impurity elements in the clip alloy of the present invention, and are not contained or preferably contained as little as possible. There is a case. If mixed, if P is 0.04% or less and S is 0.03% or less, it has almost no detrimental effect on the characteristics of the clip of the present invention, and there is little substantial influence. May be.

  The Fe-based alloy clip of the present invention is, for example, non-oxidizing and non-nitriding in an atmosphere in a temperature range of at least 450 ° C. in heat treatment after plastic processing of the metal plate made of the Fe-based alloy described above into a clip shape And can be obtained by applying a manufacturing method. Thereby, the activity of Cr in the vicinity of the clip-shaped surface can be suppressed, and the behavior of Cr being attracted and concentrated near the surface can be suppressed.

  In the manufacturing method described above, it is desirable that hydrogen gas, a rare gas, or a hydrogen gas and a rare gas are introduced into a heat treatment furnace in a temperature range of at least 450 ° C. in the heat treatment. Thereby, the atmosphere in the temperature range of at least 450 ° C. can be easily made non-oxidizing and non-nitriding. The rare gas refers to a gas composed of a homogenous element such as He, Ne, or Ar. The heat treatment includes an aging step of heating to 600 to 800 ° C., and in the final cooling of the aging step, nitrogen gas serving as a cooling medium is introduced into the heat treatment furnace in a temperature range of 450 ° C. or lower. It is desirable to do. Thereby, cooling time can be shortened rather than natural cooling, and it can contribute to the improvement of production efficiency or manufacturing cost. More desirably, the cooling medium is introduced after the temperature in the heat treatment furnace is set to 200 ° C. or less, and at this temperature, the clip being cooled is not substantially affected by the activity of Cr.

  Since the cooling medium made of hydrogen gas or rare gas does not form a compound layer containing a large amount of Cr on the surface of the clip during cooling, a Cr-deficient region in which the Cr amount is remarkably reduced is not generated. Nitrogen gas acts to attract and concentrate Cr near the surface of the clip at a high temperature. However, if the temperature in the heat treatment furnace is 450 ° C. or lower, the Cr gas is concentrated near the surface of the clip during cooling. Since no conversion region is generated, a Cr-deficient region in which the amount of Cr is remarkably reduced is not generated. Nitrogen gas is preferable because it is cheaper and has less environmental burden than hydrogen gas or rare gas.

  Therefore, the Fe-based alloy clip of the present invention obtained by the manufacturing method of the present invention described above is conventionally produced following the Cr concentration region because the concentration of Cr near the surface of the clip is suppressed. Since a Cr-deficient region in which the amount of Cr that has been significantly reduced is not generated, a Cr concentration of at least a depth of 0.1 μm to 1 μm on the surface of the clip can have 80% or more of the parent phase. That is, it does not have a Cr-depleted region that is less than 20% of the parent phase.

  In producing the Fe-based alloy clip of the present invention, for example, by including the aging step described above, intermetallic compound particles having an average particle size of 100 nm or less can be dispersed in the metal structure of the alloy for the clip, The normal temperature and high temperature strength of the clip can be increased. The aging treatment used here may be, for example, a manufacturing method in which an aging treatment is performed at 600 to 800 ° C. after a solution treatment at 900 to 1100 ° C. Alternatively, after the solution treatment, a first-stage aging treatment may be performed at 700 to 800 ° C., and then a second-stage aging treatment may be performed at 600 to 700 ° C. The aging treatment is performed after processing into the clip shape, but the solution treatment may be performed either before or after the processing into the clip shape. The heat treatment atmosphere is preferably a low oxygen atmosphere that does not form a thick oxide film. Further, although the processing to the clip shape is based on plastic processing, the processing means can be appropriately selected as necessary, such as cold processing and warm processing.

The following examples further illustrate the present invention.
A clip 1 having a shape shown in FIG. 1 (plate thickness 0.8 mm, clamp width 60 mm, depth 50 mm) is a metal plate made of an Fe-based alloy having the respective chemical components shown in Table 1 and subjected to solution treatment in advance. Made using. Specifically, it was obtained by subjecting the obtained molded body to an aging treatment after forming a clip shape by press working. This aging treatment introduces hydrogen gas to make the atmosphere in the heat treatment furnace non-oxidizing and non-nitriding, and ensures that the atmosphere in the heat treatment furnace is non-oxidizing and non-nitriding in a temperature range of at least 450 ° C. At the same time, the final cooling was performed after heating while maintaining a reduced pressure state of about 0.01 to 0.20 kPa. FIG. 2 schematically shows the heat pattern described above. As shown in FIG. 2, in the final cooling of the aging step, the temperature in the heat treatment furnace is lowered from 630 ° C., and a cooling medium made of nitrogen gas is introduced into the heat treatment furnace from the state of reaching 200 ° C. to the room temperature. Cooled down. In addition, the Example of this invention is No. 1-No. 10 and the comparative example is No. 10. 11-No. 13.

  In addition, a clip made of an Fe-based alloy of the present invention (hereinafter referred to as a clip of the present invention) No. In order to compare and verify the effects of 1 to 10, an Fe-based alloy clip (hereinafter referred to as a conventional clip) No. 1 having the same size and shape as the above-described clip of the present invention is used. 11-13 were manufactured together. In addition, in the manufacture of the conventional clip, a metal plate having the same chemical composition as the clip of the present invention and subjected to the solution treatment under the same conditions was used. However, the conditions for the aging treatment applied to the clip-shaped molded body were set. I made a difference. Specifically, the conventional clip is heated and cooled with the heat pattern shown in FIG. 3, and a cooling medium made of nitrogen gas is introduced into the heat treatment furnace from the state where the heat treatment furnace is at a temperature of 630 ° C. in the final cooling of the aging process. It was introduced and cooled to room temperature.

Next, a salt spray test (JIS-Z2371) was performed using the clip of the present invention and the conventional clip obtained by the manufacturing method described above, and the rust prevention performance (corrosion resistance) of the clip of the present invention was evaluated. In addition, the salt spray test was implemented on the to-be-tested object left still in the container on the conditions which leave it to stand for 20 hours, spraying 5% sodium chloride aqueous solution which was 35 degreeC.
After the above-described salt spray test was performed on the clip of the present invention and the conventional clip, the presence or absence of rusting was visually confirmed. Table 1 shows the presence or absence of rusting. As a result of the salt spray test, the conventional clip no. In Nos. 11 to 13, rusting was observed on almost the entire surface of the clip. In 1 to 10, no rusting was observed on the clip surface.

  Next, the clip No. 1 of the present invention after the salt spray test described above. 1 and conventional clip no. 11, the distribution state of chemical components from the surface layer of the clip toward the depth direction was measured by GD-OES (JY5000RF manufactured by Horiba, Ltd.). A GD-OES (Glow Discharge Optical Emission Spectrometry) is a glow discharge luminescence surface analyzer, which is an instrument that sequentially analyzes the content of a specified element from the surface layer of a sample to the depth direction. When a high frequency voltage is applied between the sample placed on the cathode and the anode in an argon atmosphere to cause glow discharge, argon is ionized by the glow discharge and collides with the sample while accelerating. The surface of the sample is sputtered by this collision, and the type and concentration of the element can be measured by measuring the emission spectrum of the atoms excited thereby. Note that sputtering is unstable in the extreme surface layer of about 0.05 μm from the surface of the sample, and the reliability of the measured value is significantly reduced. However, if the thickness exceeds 0.05 μm from the surface where the sputtering becomes stable, the reliability of the measured value becomes sufficient.

The measured value of the Cr concentration obtained by GD-OES of the clip of the present invention is shown in FIG. Hereinafter, the Cr concentration is expressed in mass% unless otherwise specified.
In FIG. 4, a value corresponding to 80% (11.7%) of the Cr concentration (14.7% shown in Table 1) of the parent phase of the clip of the present invention is indicated by a straight line c. With respect to this straight line c, the curve a showing the Cr concentration of the clip of the present invention is from a depth of 0.1 μm to 1.0 μm from the surface of the sample, always from the straight line c, ie 19% exceeding the value corresponding to 80% of the parent phase. It was confirmed that the rate was 17%. Although the measured values are also shown in the region less than 0.1 μm from the surface of the sample, as described above, the measurement itself is unstable in the region of about 0.05 μm from the surface and the reliability is not sufficient. It is estimated that the Cr concentration is not accurate. The same applies to the conventional clip shown in FIG.

On the other hand, the measured value of the Cr concentration obtained by GD-OES of the conventional clip is shown in FIG.
In FIG. 5, the value corresponding to 80% (11.7%) of the Cr concentration (14.7% shown in Table 1) of the parent phase of the conventional clip is indicated by a straight line c as in FIG. In contrast to this straight line c, the curve b indicating the Cr concentration of the conventional clip has a large amount of Cr from a depth of 0.05 μm to about 0.13 μm from the surface of the sample, that is, a Cr concentrated region is generated. It was confirmed that Then, following the generated Cr enriched region, there is a Cr-deficient region where the amount of Cr that does not reach the straight line c is low, and there is a region where the Cr concentration does not reach 80% of the parent phase until the depth reaches 1 μm. Admitted. In particular, from the surface depth of 0.15 μm to 0.45 μm, it was confirmed that the Cr concentration had a remarkably reduced Cr content of less than 70% of the parent phase and about 8-10%.

As described above, in the case of the conventional clip rusted on the entire surface of the clip by the salt spray test as described above, the metal structure in which the Cr concentration of at least 0.1 μm to 1 μm on the surface of the clip does not reach 80% of the parent phase. It is thought that it was rusted by having.
On the other hand, in the case of the clip of the present invention that did not rust even in the salt spray test as described above, the Cr concentration on the surface of the sample has a tendency to change in the Cr concentration at a depth of 0.1 μm or more in the curve a. Since it is considered that the conclusion of causing a rapid decrease is not reached, rusting occurs due to having a metal structure in which the Cr concentration at least 0.1 μm to 1 μm deep on the surface of the clip is 80% or more of the parent phase. It seems that it became difficult.

  Therefore, the Fe-based alloy clip of the present invention is a clip made of the Fe-based alloy described above, and the Cr concentration at least 0.1 μm to 1 μm deep on the surface of the clip is 80% or more of the parent phase. Thus, it was confirmed that the clip was not easily rusted and had excellent corrosion resistance (rust resistance).

It is a block diagram which shows an example of this invention. It is a schematic diagram which shows an example of the aging treatment in the manufacturing method of this invention. It is a schematic diagram which shows an example of the aging treatment in the conventional manufacturing method. It is a schematic diagram which shows the GD-OES measurement result which used this invention clip as a sample. It is a schematic diagram which shows the GD-OES measurement result which used the conventional clip as a sample.

Explanation of symbols

1. Clip, 2. Base, 3. 1. First side surface part Second side surface part, 5. Clamp part a. A curve showing the Cr concentration of the clip of the present invention,
b. A curve showing the Cr concentration of a conventional clip,
c. A straight line showing the Cr concentration equivalent to 80% of the matrix

Claims (4)

  C: 0.01 to 0.10% in mass%, Ni: 20.0 to 35.0%, Cr: 10.0 to 20.0%, Mo: 0.05 to 5.0%, V: 0 .10 to 1.0%, Al: 0.05 to 3.0%, Ti: 1.5 to 4.0%, B: 0.001 to 0.010%, Si: 1.0% or less, Mn : 2.0% or less, the balance being a clip made of an Fe-based alloy containing Fe and inevitable impurities, the Cr concentration at least 0.1 μm to 1 μm deep on the surface of the clip is 80% or more of the parent phase An Fe-based alloy clip characterized by being.   A heat treatment after plastic processing the metal plate made of the Fe-based alloy according to claim 1 into a clip shape, wherein the atmosphere in a temperature range of at least 450 ° C. is made non-oxidizing and non-nitriding. Manufacturing method of base alloy clip.   The method for producing an Fe-based alloy clip according to claim 2, wherein hydrogen gas, rare gas, or hydrogen gas and rare gas are introduced into a heat treatment furnace in a temperature range of at least 450 ° C in the heat treatment. .   The heat treatment includes an aging step of heating to 600 to 800 ° C, and nitrogen gas serving as a cooling medium is introduced into the heat treatment furnace in a temperature range of 450 ° C or lower in the final cooling of the aging step. Item 4. A method for producing an Fe-based alloy clip according to Item 2 or 3.