JP2007169732A - Surface treated steel sheet for gasket material of plasma television, method for manufacturing the same, and gasket material for plasma television manufactured by the manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To apply a surface treated steel sheet for a gasket material of a plasma television which is inexpensive and has excellent mechanical characteristics and a gasket material for the plasma television using the same. <P>SOLUTION: The surface treated steel sheet for the gasket material of the plasma television is characterized by having a surface treatment layer on the surface of the steel sheet consisting, by weight%, 0.03 to 0.20 C, ≤0.5% Si, 0.5 to 3.0% Mn, ≤0.1% P, ≤0.06% S, ≤0.1% Al, 0.001 to 0.0160% N, and the balance Fe and inevitable impurities. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a surface-treated steel sheet for gasket material used by being sandwiched between a rear cover (back surface exterior cover) of a plasma television set and a frame of a cabinet, a manufacturing method thereof, and a gasket material for plasma television manufactured by the manufacturing method. .

  Currently, CRT (Cathode Ray Tube), PDP (Plasma Display Panel), liquid crystal type, and the like are put into practical use as displays. Among these displays, competition in terms of price or characteristics is intensifying. The gasket material used by being sandwiched between the rear cover (backside exterior cover) of the plasma TV set and the frame of the cabinet serves not only as a gasket material but also as an electromagnetic shielding material that prevents leakage of electromagnetic waves from the inside. have. Currently, this material uses a tape coated with a conductive agent. Silver, carbon, and copper are used as the conductive agent. Since these conductive agents are deposited by a vacuum deposition method or the like, they are expensive and uneconomical. Although steel plates can be used as an alternative to tape coated with a conductive agent, conventional steel plates are inferior in spring properties, so there is a problem in terms of function as a gasket material, and a method of increasing the plate thickness to obtain appropriate strength There is, but can not be reduced in weight. When steel plate is applied to the gasket material used by being sandwiched between the rear cover (backside exterior cover) of the plasma TV set and the frame of the cabinet, force is applied to the rear cover (backside exterior cover) evenly when folded and assembled in a wave shape. This is desirable. For this reason, when applying a steel plate, springiness is required. As a method for improving the mechanical strength and the spring property, a method of rapidly cooling after heating to a recrystallization temperature or higher is disclosed (for example, see Patent Document 1). In this case, because of rapid cooling, warpage occurs in the cold-rolled steel sheet after rapid cooling, and there is a problem in terms of flatness.

Prior art document information relating to the present application includes the following.
JP-A-9-194935

  An object of the present invention is to provide a surface-treated steel sheet for a gasket material of a light-weight plasma television that is inexpensive and excellent in springiness (mechanical strength) and electromagnetic wave shielding properties, a production method thereof, and a plasma television gasket produced by the production method. The purpose is to provide materials.

In order to achieve the object, the surface-treated steel sheet for a gasket material of a plasma television according to claim 1 is C: 0.03 to 0.20%, Si: ≤ 0.5%, Mn: 0.00. 5 to 3.0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, balance Fe and unavoidable impurities It has the surface treatment layer on the surface of the steel plate. In this case, the steel sheet is, by weight, Ti: 0.01-0.2%, Nb: 0.05-0.1%, and B: 0.001-0.01%, one or two. It is desirable to further contain seeds. Furthermore, it is desirable to have a structure composed of ferrite having an average particle diameter of 5 μm to 12 μm and martensite having an average particle diameter of 5 μm or less and a volume ratio of 30% or less.
Further, the surface-treated steel sheet for a gasket material of a plasma television according to claim 4 is, by weight, C: 0.08 to 0.60%, Si: 1.0 to 3.0%, Mn: 0.5. -3.0%, P: ≤0.06%, S: ≤0.06%, Al: ≤0.1%, N: 0.0010-0.0150%, the balance Fe and unavoidable impurities It has a surface treatment layer on the surface of a steel plate.
Furthermore, the surface-treated steel sheet for a gasket material of a plasma television according to claim 5 is C: 0.09 to 0.15%, Si: ≦ 0.03%, Mn: 0.25 to 0.00. 60%, P: ≦ 0.03%, S: ≦ 0.05%, Al: 0.03-0.1%, N: 0.0010-0.0150%, balance Fe and inevitable impurities It has a surface treatment layer on the surface of a steel plate. It is desirable that the surface treatment layer described above is Zn or Ni plating.

The manufacturing method of the surface-treated steel sheet for a gasket material of a plasma television according to claim 7 is C: 0.03-0.20%, Si: ≦ 0.5%, Mn: 0.5-3. Continuous casting cast consisting of 0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, balance Fe and inevitable impurities The pieces are hot-rolled so that the average crystal grain size is 5 μm or less, pickled, then cold-rolled with a rolling rate of 30 to 90%, and further plated with Zn or Ni. And
The manufacturing method of the surface-treated steel sheet for a gasket material of a plasma television according to claim 8 is C: 0.03-0.20%, Si: ≦ 0.5%, Mn: 0.5-3. Continuous casting cast consisting of 0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, balance Fe and inevitable impurities The pieces are hot-rolled so that the average crystal grain size is 5 μm or less, pickled, then cold-rolled with a rolling rate of 30 to 90%, and then continuously annealed at 700 ° C. or higher or a box at 550 ° C. or higher. It is characterized by performing die annealing, further performing secondary rolling or temper rolling with a rolling rate of 60% or less, and further applying Zn or Ni plating to the surface.
The method for producing a surface-treated steel sheet for a gasket material of a plasma television according to claim 9 is C: 0.03-0.20%, Si: ≦ 0.5%, Mn: 0.5-3. Continuous casting cast consisting of 0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, balance Fe and inevitable impurities The pieces are hot-rolled so that the average crystal grain size is 5 μm or less, pickled, then cold-rolled with a rolling rate of 30 to 90%, and then subjected to continuous annealing or box-type annealing, and then the rolling rate Secondary rolling at 60% or less, followed by continuous annealing at 700 ° C. or higher or box annealing at 550 ° C. or higher, further subjected to tertiary rolling or temper rolling at a rolling rate of 60% or lower, and the surface Zn or Ni plating is applied to the substrate. In this case, the steel sheet is, by weight, Ti: 0.01-0.2%, Nb: 0.005-0.1%, and B: 0.001-0.01%, one or two. It is desirable to further contain seeds.

The manufacturing method of the surface treatment steel plate for gasket materials of a plasma television of Claim 11 is weight%, C: 0.08-0.60%, Si: 1.0-3.0%, Mn: 0.00. 5 to 3.0%, P: ≦ 0.06%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, balance Fe and unavoidable impurities The obtained continuous cast slab is hot-rolled, pickled, cold-rolled at a rolling rate of 50 to 90%, and further plated with Zn or Ni.
The manufacturing method of the surface treatment steel plate for gasket materials of the plasma television of Claim 12 is weight%, C: 0.08-0.60%, Si: 1.0-3.0%, Mn: 0.00. 5 to 3.0%, P: ≦ 0.06%, S ≦: 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, balance Fe and unavoidable impurities The continuous cast slab is subjected to hot rolling, pickling, cold rolling at a rolling rate of 50 to 90%, and annealing is performed at 630 to 870 ° C. by continuous annealing or 500 to 750 ° C. by batch annealing, It is characterized by performing temper rolling and further applying Zn or Ni plating to the surface.

The method for producing a surface-treated steel sheet for a gasket material of a plasma television according to claim 13 is, by weight%, C: 0.09 to 0.15%, Si: ≤ 0.03%, Mn: 0.25 to 0. .60%, P: ≦ 0.03%, S: ≦ 0.05%, Al: 0.03-0.1%, N: 0.0010-0.0150%, balance Fe and unavoidable impurities The obtained continuous cast slab is subjected to hot rolling, pickling, cold rolling with a rolling rate of 75% or more, annealing, temper rolling, and further, Zn or Ni plating is applied to the surface.
A gasket material for a plasma television according to a fourteenth aspect is manufactured using the surface-treated steel sheet for a gasket material for a plasma television according to any one of the first to sixth aspects.
A gasket material for a plasma television according to a fifteenth aspect is manufactured using the method for producing a surface-treated steel sheet for a gasket material for a plasma television according to any one of the seventh to thirteenth aspects.

  Since the surface-treated steel sheet for a gasket material of a plasma television according to the present invention is inexpensive and excellent in spring properties (mechanical strength) and electromagnetic wave shielding properties, an inexpensive plasma television gasket material can be provided.

  Hereinafter, embodiments of the present invention will be described in detail.

(Embodiment 1)
The steel components of the surface-treated steel sheet for the gasket material of the plasma television of Embodiment 1 are in weight%, C: 0.03 to 0.20%, Si: ≦ 0.5%, Mn: 0.5 to 3.0. %, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, the balance Fe and inevitable impurities. Moreover, it is more desirable to further contain one or two of Ti: 0.01 to 0.2%, Nb: 0.005 to 0.1% and B: 0.001 to 0.01%.

  C is preferably 0.03% by weight or more because of the high tempering degree of the surface-treated steel sheet for plasma TV gasket materials. However, if C exceeds 0.2% by weight, the amount of precipitated carbide increases and the workability of the steel sheet decreases, and at the same time, the load of cold rolling increases, the shape deteriorates, and the plate-passability in the continuous annealing process. It causes a decrease in productivity such as inhibition. Therefore, in this invention, the upper limit of C component shall be 0.20 weight%.

  Si has a large solid solution strengthening function in steel and is an effective element for obtaining toughness. Therefore, 0.1% by weight or more is necessary. Further, Si is better in terms of material strengthening, but the upper limit is set to 0.50% by weight because it causes an increase in cold rolling load and deterioration of the shape.

  Mn is a component necessary for preventing red heat embrittlement during hot rolling due to the impurity S, and at the same time, as in the case of C, the Mn component is 0.5% by weight in order to give a high tempering degree to the original plate. That's it. However, as is the case with C here, too much load of cold rolling, crack generation during slab rolling, deterioration of shape, threadability hindrance in continuous annealing process, etc., cause productivity reduction, The Mn component has an upper limit of 3.0% by weight.

  P is a crystal grain refining component and is added at a certain ratio because it increases the strength of the original plate, but it inhibits corrosion resistance. As an application of the present invention, when P exceeds 0.10% by weight, the corrosion resistance, particularly the hole resistance, is remarkably lowered, so the upper limit of the P component is set to 0.10% by weight.

  S is an impurity component that causes red-hot brittleness during hot rolling, and it is desirable that S be as small as possible. Unavoidable. Since red heat brittleness due to a small amount of residual S can be reduced by Mn, the upper limit of the S component is set to 0.06% by weight.

  Al is added to the steel bath as a deoxidizer during steelmaking, but when it exceeds 0.10% by weight, it is used as an oxidation inhibitor during continuous casting and as a mold powder used as an anti-seizure agent for continuous casting. Oxygen and excess Al react to inhibit the original powder effect. Therefore, the Al amount is 0.10% by weight or less.

  N, like C and Mn, gives a high degree of tempering to the original plate. Although it is a necessary component for strengthening the proof stress, if it is less than 0.001% by weight, it will cause difficulty in steelmaking, while if it exceeds 0.0160% by weight, the yield of ferronitride added during steelmaking Is significantly deteriorated and lacks stability, and at the same time, anisotropy during press molding is significantly deteriorated. Further, since cracks are generated on the surface of the continuous cast piece, resulting in casting defects, the N component range is set to 0.001 to 0.0160% by weight in the present invention.

  Ti and Nb are easy to form a carbonitride compound and have the effect of refining crystal grains. Nb has a lower limit of 0.005% by weight, and Ti has 0.01% by weight. Moreover, when there are too many any elements, the recrystallization temperature must be raised and the continuous annealing temperature must be raised, resulting in an increase in cost. Therefore, the upper limit of Ti is 0.2% by weight, and the upper limit of Nb is 0.1% by weight.

  B is an element necessary for obtaining martensite, which is an important structure of the present invention, and is easily segregated at grain boundaries, and has the effect of reducing crystal grain coarsening and refining crystal grains. Accordingly, 0.001% by weight or more is added. Moreover, since the effect will be saturated even if too much, the upper limit of B component shall be 0.01 weight% from reasons, such as cost.

Hot rolling Steel slab heating temperature in the hot rolling process is not specified in the present invention, but it is 1100 ° C. or less from the viewpoint of positive decomposition and dissolution of N and stable securing of the hot finish rolling temperature. desirable. When the hot rolling finishing temperature is less than 850 ° C., the crystal structure of the hot steel strip is mixed and coarsened, and the desired strength cannot be obtained. Therefore, the hot rolling finishing temperature is preferably 850 ° C. or more. .
Although the rolling rate and cooling conditions in hot rolling finish rolling are not specified, in order to obtain high strength, it is desirable to quench rapidly under high pressure as much as possible so that the average crystal grain size is 5 μm or less. Further, a structure in which martensite is dispersed in ferrite having an average particle diameter of 5 μm or less is desirable.
The coiling temperature is not specified in the present invention, but the coiling temperature is preferably 700 ° C. or lower in order to suppress the coarsening of crystal grains.

Cold rolling The steel sheet hot-rolled in the above component system is cold-rolled, and this cold rolling rate is an important strength factor of the present invention together with the components, and in order to obtain the desired strength, 30 to 90 %.

Annealing The material subjected to cold rolling at a rolling rate of 30 to 90% as described above is degreased in the cleaning process, and then annealed at a temperature of 700 ° C. or higher for continuous annealing or 550 ° C. or higher for batch annealing. The upper limit temperature is 830 ° C. for continuous annealing and 700 ° C. for box annealing.

Secondary cold rolling The secondary cold rolling after annealing increases the strength when the rolling rate is high, which is desirable, but the elongation is small, so when performing the secondary cold rolling, the rolling rate is set to 60% or less. . Then, if necessary, surface roughness is imparted by temper rolling.
The cold-rolled steel sheet produced as described above has a structure composed of ferrite having an average particle diameter of 5 μm to 12 μm and martensite having an average particle diameter of 5 μm or less and a volume ratio of 30% or less. Is desirable. For spring applications, it is more desirable that ferrite having an average particle diameter of 2 μm or less and martensite having an average particle diameter of 5 μm or less have a structure composed of 6% to 30% by volume. In processing applications, it is more desirable to have a structure in which ferrite having an average particle diameter of 3 μm to 12 μm and martensite having an average particle diameter of 5 μm or less have a volume ratio of 5% or less. In this way, by controlling the ferrite grain size and the volume ratio of martensite in combination with the cold rolling rate and the annealing conditions, the cold rolled steel sheet, which is important for toughness, has a finer structure and requires workability. It is possible to obtain optimum characteristics for each cold rolled steel sheet by increasing the particle size.

(Embodiment 2)
The steel components of the surface-treated steel sheet for gasket material of the plasma television of Embodiment 2 are in weight%, C: 0.08 to 0.60%, Si: 1.0 to 3.0%, Mn: 0.5 to 3 0.0%, P: ≦ 0.06%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, the balance Fe and inevitable impurities.

  Since C is added to a high tempering degree to the surface-treated steel sheet for a gasket material of a plasma television, C is preferably 0.08% by weight or more. On the other hand, if the C component exceeds 0.60% by weight, the amount of precipitated carbide increases, resulting in a decrease in workability of the surface-treated steel sheet for plasma TV gasket material, and at the same time, an increase in cold rolling load and deterioration in shape , Which causes a decrease in productivity, such as hindrance to plateability in the continuous annealing process. Therefore, in the present invention, the upper limit value of the C component is set to 0.60% by weight.

  Mn is a component necessary to prevent red hot brittleness during hot rolling due to S as an impurity, and at the same time, in order to give a high tempering degree to the surface-treated steel sheet for the plasma TV gasket material, as in C above, The Mn component is 0.5% by weight or more. However, as is the case with C here, too much load of cold rolling, crack generation during slab rolling, deterioration of shape, threadability hindrance in continuous annealing process, etc., cause productivity reduction, The upper limit is set to 3.0% by weight.

  P is a crystal grain refining component, and is added at a certain ratio because it increases the strength of the surface-treated steel sheet for gasket material of plasma televisions, but it inhibits corrosion resistance. As an application of the present invention, when P exceeds 0.06% by weight, the corrosion resistance, particularly the hole resistance, is remarkably lowered, so the upper limit is set to 0.06% by weight.

  S is an impurity component that causes red-hot brittleness during hot rolling, and it is desirable that S be as small as possible. Unavoidable. Since red heat brittleness due to a small amount of residual S can be reduced by Mn, the upper limit of the S component is set to 0.06% by weight.

  Al is added to the steel bath as a deoxidizer during steelmaking, but if it exceeds 0.10% by weight, it is contained in the mold powder used as an oxidation inhibitor during continuous casting and as an anti-seizure agent on the mold in continuous casting. Oxygen and excess Al react to inhibit the original powder effect. Therefore, the Al amount is 0.10% by weight or less.

  N, like C and Mn, gives a high tempering degree to the surface-treated steel sheet for a gasket material of a plasma television. Although it is a necessary component for strengthening the proof stress, if it is less than 0.001% by weight, it causes difficulty in steelmaking. On the other hand, if it exceeds 0.0150% by weight, the yield of ferronitride added during steelmaking is reduced. Remarkably lacking in stability, and at the same time, anisotropy during press molding is significantly deteriorated. Furthermore, cracks are generated on the surface of the continuous cast piece, resulting in casting defects. Therefore, in the present invention, the N component range is set to 0.001 to 0.0150% by weight. More desirably, the content is 0.0021 to 0.0150% by weight.

  Si is a major feature of the present invention. Si has a large solid solution strengthening ability in steel and is an effective element for obtaining toughness. Therefore, 1.0% by weight or more is necessary. Further, the higher the material reinforcement, the better. However, if it exceeds 3.0% by weight, the load of cold rolling is increased and the shape is deteriorated, so the upper limit is set to 3.0% by weight.

Hot rolling Steel slab heating temperature in the hot rolling process is not specified in the present invention, but it is 1100 ° C. or less from the viewpoint of positive decomposition and dissolution of N and stable securing of the hot finish rolling temperature. desirable. When the hot rolling finishing temperature is less than 850 ° C., the crystal structure of the hot steel strip is mixed and coarsened, and the desired strength cannot be obtained. Therefore, the hot rolling finishing temperature is preferably 850 ° C. or more. .

  The winding temperature is 450 ° C to 650 ° C. 450 ° C. is set as the lower limit in consideration of the quality stability in the width direction and the longitudinal direction of the coil during hot rolling. Further, if the coiling temperature exceeds 650 ° C., the crystal grain size becomes large during hot rolling and continuous annealing, which causes a defect during processing. Therefore, the coiling temperature is preferably 650 ° C. or less.

  The steel sheet hot-rolled in the above component system is cold-rolled, and this cold rolling rate is an important strength factor of the present invention together with the components, and is performed at 50 to 90% in order to obtain the desired strength. .

  The material subjected to 50 to 90% cold rolling as described above is degreased in the cleaning step, and then subjected to continuous annealing at 630 to 870 ° C, preferably 680 to 870 ° C. Alternatively, batch annealing is performed at 500 to 750 ° C., preferably 600 to 750 ° C. The annealing time may be within the range to be recrystallized. In particular, when the thickness is 0.6 mm or less, continuous annealing is desirable, and when the thickness exceeds 0.6 mm, box annealing is desirable.

Temper Rolling After annealing, temper rolling with a rolling rate of 1-2% is performed. During temper rolling, surface roughness is imparted if necessary. If the rolling rate is less than 1%, stretcher strain tends to occur. Conversely, if it exceeds 2%, the workability deteriorates and there is a problem.

(Embodiment 3)
The steel components of the surface-treated steel sheet for gasket material of the plasma television of Embodiment 3 are in weight%, C: 0.09 to 0.15%, Si: ≦ 0.03%, Mn: 0.25 to 0.60. %, P: ≦ 0.03%, S: ≦ 0.05%, Al: 0.03 to 0.1%, N: 0.0010 to 0.0150%, the balance Fe and inevitable impurities.

  Since C is added to the high tempering degree to the surface-treated steel sheet for the gasket material of the plasma television, C is preferably 0.09% by weight or more. On the other hand, if the C component exceeds 0.15% by weight, the amount of carbide precipitation increases, resulting in a decrease in workability of the steel sheet, and at the same time, an increase in cold rolling load, shape deterioration, and sheet passing in a continuous annealing process. Cause a decrease in productivity. Therefore, in the present invention, the upper limit value of the C component is set to 0.15% by weight.

  Mn is a component necessary for preventing red heat embrittlement during hot rolling due to the impurity S, and at the same time, in the same manner as C, in order to give a high tempering degree to the steel sheet, the Mn component is 0.25% by weight. That's it. However, as is the case with C here, too much load of cold rolling, crack generation during slab rolling, deterioration of shape, threadability hindrance in continuous annealing process, etc., cause productivity reduction, The upper limit is 0.60% by weight.

  P is a crystal grain refining component and is added at a certain ratio because it increases the strength of the steel sheet, but it inhibits corrosion resistance. As an application of the present invention, when P exceeds 0.03% by weight, the corrosion resistance, particularly the hole resistance is remarkably lowered, so the upper limit is set to 0.03% by weight.

  S is an impurity component that causes red-hot brittleness during hot rolling, and it is desirable that S be as small as possible. Unavoidable. Since red heat brittleness due to a small amount of residual S can be reduced by Mn, the upper limit of the S component is set to 0.05% by weight.

  Al is added to the steel bath as a deoxidizer during steelmaking, but if it exceeds 0.1% by weight, it is contained in the mold powder used as an oxidation inhibitor during continuous casting and as an anti-seizure agent on the mold in continuous casting. Oxygen and excess Al react to inhibit the original powder effect. Therefore, the Al amount is 0.10% by weight or less.

  N, like C and Mn, gives a high tempering degree to the steel sheet. Although it is a necessary component for strengthening the proof stress, if it is less than 0.001% by weight, it will cause difficulty in steelmaking, while if it exceeds 0.0150% by weight, the yield of ferronitride added during steelmaking Is significantly deteriorated, and the stability at the same time is deteriorated. Furthermore, cracks are generated on the surface of the continuous cast piece, resulting in casting defects. Therefore, in the present invention, the N component range is set to 0.001 to 0.0150% by weight. More desirably, the content is 0.0021 to 0.0150% by weight.

  If a large amount of Si is contained, there is a problem in terms of corrosion resistance, and the content is made 0.03 wt% or less.

Hot rolling Steel slab heating temperature in the hot rolling process is not specified in the present invention, but it should be 800 ° C. or higher from the standpoint of positive decomposition and dissolution of N and stable securing of the hot finish rolling temperature. desirable. When the hot rolling finishing temperature is less than 800 ° C., the crystal structure of the hot steel strip is mixed and coarsened, and the desired strength cannot be obtained. Therefore, the hot rolling finishing temperature is preferably 800 ° C. or more. .

  The winding temperature is 400 ° C to 650 ° C. In consideration of the quality stability in the width direction and the longitudinal direction of the coil during hot rolling, 400 ° C. is set as the lower limit. Further, if the coiling temperature exceeds 650 ° C., the crystal grain size becomes large during hot rolling and continuous annealing, which causes a defect during processing. Therefore, the coiling temperature is preferably 650 ° C. or less.

Cold Rolling A steel sheet hot-rolled with the above component system is cold-rolled, and this cold rolling rate is an important strength factor of the present invention together with the components. In order to obtain the desired strength, 75% or more To do. If it is less than 75%, the strength tends to be insufficient.

Annealing The material subjected to cold rolling with a cold rolling ratio of 75% or more as described above is subjected to degreasing in the cleaning step, and then subjected to continuous annealing at 600 to 720 ° C. for 30 seconds to 10 minutes. Alternatively, box annealing is performed at 500 to 580 ° C. for 1 to 8 hours. It is sufficient that these annealing times are within the range to be recrystallized. In particular, when the thickness is 0.6 mm or less, continuous annealing is desirable, and when the thickness exceeds 0.6 mm, box annealing is desirable.

Temper Rolling After annealing, temper rolling with a rolling rate of 1-2% is performed. During temper rolling, surface roughness is imparted if necessary. If the rolling rate is less than 1%, stretcher strain tends to occur. Conversely, if it exceeds 2%, the workability deteriorates and there is a problem.

  Next, examples of the steel plates according to the first to third embodiments created in this manner include those obtained by subjecting sheet-like and coil-like steel plates to surface treatment. In particular, as surface treatment, zinc plating, nickel alloy plating containing one or more of nickel, cobalt, iron, aluminum, magnesium or molybdenum, nickel plating, nickel alloy plating, or further these plating surfaces Those treated with a treatment solution containing organic or inorganic substances can be used. As the zinc or zinc alloy plating method, an electroplating method, a hot dipping method or a vacuum deposition plating method can be applied.

As the treatment liquid containing an organic substance, a solution containing a urethane resin, polytetrafluoroethylene and colloidal silica, or a solution containing a urethane resin, an amine preservative and colloidal silica can be used. An electrolytic chromic acid-treated steel sheet or tin-plated steel sheet having a two-layer structure in which the lower layer is metallic chromium and the upper layer is chromium hydrated oxide can also be applied.
As the treatment liquid containing an inorganic substance, a solution containing silicic acid or silicate and lithium hydroxide, a solution containing a phosphate such as zinc phosphate, or a solution containing chromic acid can be used.
When processing using the processing liquid containing an organic substance or an inorganic substance, a known processing method such as an immersion method, a method of drawing after immersion, a roll coating method, or a spray coating method can be applied. When processing with a solution containing chromic acid, it may be performed by electrolytic treatment.

About the Example and comparative example which are this invention, Table 1 shows manufacturing conditions, such as a steel component and a rolling rate, and Table 2 shows the characteristic evaluation result. Examples 1 to 5 relate to Embodiment 1, Examples 6 to 8 relate to Embodiment 2, and Examples 9 to 12 relate to Embodiment 3. In Examples 1 to 12 and Comparative Examples 1 to 4, the steel pieces were subjected to surface treatment by hot rolling, pickling, cold rolling, continuous annealing, and temper rolling. In Table 1, the finishing temperature and the coiling temperature are hot rolling conditions, the rolling rate is the rolling rate during cold rolling, and the heating temperature is the soaking temperature during continuous annealing. The soaking temperature was maintained for 50 seconds. As the surface treatment, zinc 1 wt% cobalt-0.1 wt% molybdenum plating is performed on both sides at 10 g / m ² , 300 g / L of water-based urethane resin as a solid content, 50 g / L of amine-based anticorrosive agent, water-dispersed silica A steel plate plated with zinc-1 wt% cobalt-0.1 wt% molybdenum was immersed in a treatment solution containing 250 g / L. After dipping, the film was squeezed with a roll and dried at 90 ° C. so that the thickness after drying was 0.5 μm to obtain a surface-treated steel sheet.

<Evaluation of mechanical properties>
About Examples 1-12 and Comparative Examples 1-4, it was set as the JIS5 test piece, and Yp (yield point strength), TS (tensile strength), and TEl (elongation) shown in Table 2 were measured.
<Measurement of hardness (HR-30T)>
HR-30T was measured with a Rockwell hardness meter.
<Spring evaluation>
FIG. 1 shows a compression test process which is a test method for evaluating spring properties. 1A shows a state before compression of the processed bead portion, FIG. 1B shows a state where a compression load is applied, and FIG. 1C shows a state where the compression load is unloaded. Show. As shown in FIG. 1, a compression load was applied to the bead portion from above with a compression tester. After the unloading, the spring property was evaluated as acceptable when the restoration amount (T1) exceeded 30% with respect to the compression amount (T). On the other hand, when the amount was 30% or less, the spring property was evaluated as unacceptable.

From Tables 1 and 2, Examples 1 to 12 have large TS (tensile strength) and Yp (yield point strength), high strength, and excellent material properties. In the evaluation of the spring property, all of Examples 1 to 12 had a good spring property after the unloading, with the restoration amount (T1) exceeding 30% with respect to the compression amount (T). Accordingly, Examples 1 to 12 can be applied as gasket materials for plasma televisions.
In Comparative Examples 1 to 4, the strength (TS) is small, and in terms of springiness, the Comparative Examples 1 to 4 have a restoration amount (T1) of 30% or less with respect to the compression amount (T) after unloading. There was a problem in terms of springiness. Thus, any of Comparative Examples 1 to 4 cannot be applied as a gasket material for a plasma television.

  The surface-treated steel sheet for a gasket material of a plasma television according to the present invention is excellent in mechanical properties and spring properties and can be used as a gasket material for a plasma television. Since it can be used as an alternative to an expensive conductive agent-coated tape, an inexpensive plasma TV gasket material can be provided.

It is the schematic of the test method for evaluating the spring property of this invention.

Claims (15)

% By weight, C: 0.03 to 0.20%, Si: ≦ 0.5%, Mn: 0.5 to 3.0%, P: ≦ 0.1%, S: ≦ 0.06%, A surface treatment for a gasket material of a plasma television characterized by having a surface treatment layer on the surface of a steel plate comprising Al: ≦ 0.1%, N: 0.0010 to 0.0160%, the balance Fe and unavoidable impurities steel sheet. Steel sheets constituting the surface-treated steel sheet for plasma television gasket materials are in weight percent, Ti: 0.01 to 0.2%, Nb: 0.05 to 0.1%, and B: 0.001 to 0.01. The surface-treated steel sheet for a gasket material for a plasma television according to claim 1, further comprising 1 type or 2 types. The surface-treated steel sheet for gasket material of the plasma television has a structure composed of ferrite having an average particle diameter of 5 μm to 12 μm and martensite having an average particle diameter of 5 μm or less and a volume ratio of 30% or less. A surface-treated steel sheet for a gasket material of a plasma television according to claim 1 or 2. C: 0.08-0.60%, Si: 1.0-3.0%, Mn: 0.5-3.0%, P: ≦ 0.06%, S: ≦ 0.0. Gasket material for plasma television characterized by having a surface treatment layer on the surface of a steel plate comprising 06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, balance Fe and inevitable impurities Surface treated steel sheet. % By weight, C: 0.09 to 0.15%, Si: ≤0.03%, Mn: 0.25 to 0.60%, P: ≤0.03%, S: ≤0.05%, A plasma TV gasket material comprising a surface treatment layer on the surface of a steel plate comprising Al: 0.03-0.1%, N: 0.0010-0.0150%, the balance Fe and unavoidable impurities Surface treated steel sheet. The surface-treated steel sheet for a plasma television gasket material according to any one of claims 1 to 5, wherein the surface treatment layer is made of Zn or Ni plating. % By weight, C: 0.03 to 0.20%, Si: ≦ 0.5%, Mn: 0.5 to 3.0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, the continuous cast slab composed of the balance Fe and inevitable impurities, hot-rolled so that the average crystal grain size is 5 μm or less, A method for producing a surface-treated steel sheet for a gasket material of a plasma television, characterized in that after pickling, cold rolling is performed at a rolling rate of 30 to 90%, and further Zn or Ni plating is applied to the surface. % By weight, C: 0.03 to 0.20%, Si: ≦ 0.5%, Mn: 0.5 to 3.0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, the continuous cast slab composed of the balance Fe and inevitable impurities, hot-rolled so that the average crystal grain size is 5 μm or less, After pickling, cold rolling with a rolling rate of 30 to 90% is performed, followed by continuous annealing at 700 ° C. or higher or box annealing at 550 ° C. or higher, and further secondary rolling or temper rolling at a rolling rate of 60% or lower. A method for producing a surface-treated steel sheet for a gasket material of a plasma television, wherein the surface is further plated with Zn or Ni. % By weight, C: 0.03 to 0.20%, Si: ≦ 0.5%, Mn: 0.5 to 3.0%, P: ≦ 0.1%, S: ≦ 0.06%, Al: ≦ 0.1%, N: 0.0010 to 0.0160%, the continuous cast slab composed of the balance Fe and inevitable impurities, hot-rolled so that the average crystal grain size is 5 μm or less, After pickling, cold rolling with a rolling rate of 30 to 90% is performed, then continuous annealing or box annealing is performed, then secondary rolling with a rolling rate of 60% or less is performed, and then continuous annealing at 700 ° C. or higher or Surface for plasma TV gasket material, characterized by performing box-type annealing at 550 ° C. or higher, further performing tertiary rolling or temper rolling at a rolling rate of 60% or lower, and further applying Zn or Ni plating to the surface. A method for producing a treated steel sheet. Steel sheets constituting the surface-treated steel sheet for gasket material of plasma televisions are in weight%, Ti: 0.01-0.2%, Nb: 0.005-0.1%, and B: 0.001-0.01. The method for producing a surface-treated steel sheet for a gasket material of a plasma television according to any one of claims 5 to 7, further comprising 1 type or 2 types. C: 0.08-0.60%, Si: 1.0-3.0%, Mn: 0.5-3.0%, P: ≦ 0.06%, S: ≦ 0.0. 06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, continuous cast slab made of balance Fe and inevitable impurities, hot rolled, pickled, rolling rate 50 to 90% A method for producing a surface-treated steel sheet for a gasket material of a plasma television, wherein the surface is cold-rolled and further plated with Zn or Ni. C: 0.08-0.60%, Si: 1.0-3.0%, Mn: 0.5-3.0%, P: ≦ 0.06%, S ≦: 0. 06%, Al: ≦ 0.1%, N: 0.0010 to 0.0150%, continuous cast slab made of balance Fe and inevitable impurities, hot rolled, pickled, rolling rate 50 to 90% It is characterized in that it is cold-rolled and subjected to continuous annealing at 630 to 870 ° C. or batch annealing at 500 to 750 ° C., then tempered rolling, and further plated with Zn or Ni. Manufacturing method of surface-treated steel sheet for gasket material of plasma television % By weight, C: 0.09 to 0.15%, Si: ≤0.03%, Mn: 0.25 to 0.60%, P: ≤0.03%, S: ≤0.05%, A continuous cast slab made of Al: 0.03-0.1%, N: 0.0010-0.0150%, the balance Fe and inevitable impurities is hot-rolled, pickled, and the rolling rate is 75% or more. A method for producing a surface-treated steel sheet for a gasket material of a plasma television, characterized by subjecting the surface to cold rolling, annealing, temper rolling, and further applying Zn or Ni plating to the surface. A gasket material for a plasma television manufactured using the surface-treated steel sheet for a gasket material for a plasma television according to any one of claims 1 to 6. A gasket material for a plasma television manufactured by the method for producing a surface-treated steel sheet for a gasket material for a plasma television according to any one of claims 7 to 13.

Images