KR20040075207A - ELECTROLYTE FOR NANOCRYSTALLINE Fe-Ni ALLOYS WITH LOW THERMAL EXPANSION AND THE PROCESS OF PRODUCING THE SAME - Google Patents

Abstract

PURPOSE: A plating (forming) solution and process conditions are provided to manufacture a low thermal expansion property Fe-Ni alloy sheet having low thermal expansion coefficient of 9 μm/m·K or less by electrodeposition or electroforming. CONSTITUTION: The electrolyte for manufacturing Fe-Ni alloy comprises 1 liter of water; 25 to 73 g of FeSO4·7H2O (ferrous sulfate), FeCl2·4H2O (ferrous chloride) or a mixture thereof; 97 g of NiSO4·6H2O (nickel sulfate), NiCl2·6H2O (nickel chloride), Ni(NH2SO3)2 (nickel sulfamate) or a mixture thereof; 20 to 30 g of H3BO3 (boric acid); 1 to 3 g of C7H4NO3SNa (sodium saccharin); 0.1 to 0.3 g of C12H25O4SNa (sodium lauryl sulfate), and 20 to 40 g of NaCl (sodium chloride), wherein the electrolyte has pH of 2 to 4, current density of 50 to 100 mS/cm¬2 and temperature of 50 to 60 deg.C.

Description

Plating (molding) liquid for manufacturing nanocrystalline iron-nickel alloy having low thermal expansion and manufacturing method therefor {ELECTROLYTE FOR NANOCRYSTALLINE Fe-Ni ALLOYS WITH LOW THERMAL EXPANSION AND THE PROCESS OF PRODUCING THE SAME}

An object of the present invention is to provide a plating method for producing a Fe-Ni alloy sheet having a low thermal expansion property having a thermal expansion coefficient of 9 μm / m · K or less by using an electroplating or electroforming method. Molding) solution and process conditions.

Fe-Ni alloys exhibit various properties depending on the Ni content, and low thermal expansion properties occur when the Ni content is in the range of 20% to 50% by weight (DR Rancourt, S. Chehab and G. Lamarche, J. Mag. Mag). Mater. 78 (1989) 129). Among these alloys, 64% Fe-36% Ni, called Invaralloy, have a coefficient of thermal expansion close to zero, and since Guillaume first invented in 1897 (CE Guillaume, CR Acad. Sci. Paris 124 (1897) It is produced as a representative low thermal expansion alloy and has been widely used commercially.

An example of using inva alloys is a shadow mask which is an integral part of a cathode ray tube (CRT) for color monitors in TVs and personal computers (PCs). The role of the shadow mask is to induce an electron beam from the electron gun to impinge the phosphor through the hole of the shadow mask, but in the process, about two thirds of the total electron beam collides with the shadow mask to raise the temperature. Therefore, in order to maintain accurate hole size and shape even when the temperature of the shadow mask increases, the resolution of the color monitor can be obtained only by using a low thermal expansion material, that is, an inva alloy. In addition to CRTs, shadow masks made of inva alloy are expected to be used in field emission displays (FEDs) for flat panel monitors.

Another example of using a low thermal expansion Fe-Ni alloy is a lead frame supporting an integrated circuit (IC) chip. The lead frame is a component that electrically connects the chip and the outside. The thermal expansion coefficient of the lead frame and the material used for the chip are similar to each other to reduce the thermal stress to ensure the life of the IC chip. In this case, a Fe-Ni alloy is used in which the Ni content is changed from 40% to 49% according to the material selection of the chip. In addition, Fe-Ni alloys for low thermal expansion are used in bimetals, glass / metal seals, electrical components, and internal combustion engine pistons with varying Ni content.

There are various methods of manufacturing the above Fe-Ni alloy sheet, but cold rolling is mainly used. When cold rolling is used, vacuum melting, forging, hot rolling, normalizing, primary cold rolling, intermediate annealing, secondary cold rolling, and final annealing in a reducing atmosphere are required. In order to manufacture a thin plate, multi-stage rolling must be performed (see US Patent 494834), which is not only difficult to obtain a homogeneous product but also a high manufacturing cost. In addition, there is a problem that the coefficient of thermal expansion is sensitive to changes in impurities and process conditions involved in the process (see Metals Handbook, 9th ed. Vol. 3, ASM (1980) 889).

In order to overcome the limitations of the conventional manufacturing method, a lot of researches have recently been made on the production of Fe-Ni alloys by electroplating (molding). However, since the formulation and process conditions of the electrolyte are difficult, it contains 20 to 50 wt% of Ni. In the electroforming of the Fe-Ni alloy, a desirable product has not yet been produced. For example, as a plating solution and process conditions of the patent application (Application No. 10-2001-0019169), Permalloy (20% Fe-80% Ni, Permalloy) is produced reproducibly, while Invar alloy and Ni content For the production of Fe-Ni alloys of less than 50wt%, it is necessary to mix the plating (molding) solution and fundamentally change the process conditions.

The present invention has been proposed to overcome the above problems, and the composition and process conditions of the plating (molding) liquid for producing in a single-step electroforming method so that the Fe-Ni alloy having a desired coefficient of thermal expansion value has an accurate alloy composition The purpose is to provide.

Figure 1 is a schematic diagram of the electroplating (molding) apparatus for producing a Fe-Ni alloy sheet in the present invention.

The above object of the present invention is achieved by obtaining an accurate Fe-Ni alloy composition by the composition of the ideally formulated electrolyte solution and the specific process conditions.

The electrolyte proposed in the present invention is FeSO ₄ · 7H ₂ O (Ferrous Sulfate), NiSO ₄ · 6H ₂ O (Nickel Sulfate), NiCl ₂ · 6H ₂ O (Nickel Chloride), FeCl ₂ · 4H ₂ O (Ferrous Chloride) And Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) was used as the basis, and boric acid (H ₃ BO ₃ , Boric acid) 20-30g / l and saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) A solution containing 1 to 3 g / l, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) and 0.1 to 0.3 g / l, and sodium chloride (NaCl, Sodium Chloride) 20 to 40 g / l. Among them, boric acid (H ₃ BO ₃ , Boric acid) is 22-25g / l, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) is 2.0-2,4g / l and sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1-0.2 g / l and sodium chloride (NaCl, Sodium Chloride) 30-32 g / l are shown to show more favorable effect. The iron compound and the nickel compound are released as ions in the electrolyte, and then electrodeposited with Fe-Ni during electroplating (molding), boric acid is a pH buffer, saccharin is a stress relaxation agent of plating (molding) material, and sodium chloride is electrolyte conductivity. Add for improvement. During electroplating (molding), the pH of the electrolyte is maintained in the range of 2 to 4, the current density is 50 to 100mA / cm ² , the temperature of the electrolyte is carried out at 50 to 60 ℃.

Table 1-6 shows the composition of the plating (molding and electrolytic) solution for producing a Fe-Ni alloy thin plate having a composition in the range of 20 to 50wt% Ni under the above process conditions. .

FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and NiSO ₄ · 6H ₂ O (Nickel Sulfate) solution Example FeSO ₄ 7H ₂ O (g) NiSO ₄ · 6H ₂ O (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) One 28 97 22 0.1 2.0 32 50.4 2 33 97 22 0.1 2.0 32 45.3 3 38 97 22 0.1 2.0 32 41.0 4 43 97 22 0.1 2.0 32 38.8 5 48 97 22 0.1 2.0 32 36.4 6 53 97 22 0.1 2.0 32 34.2 7 58 97 22 0.1 2.0 32 32.3 8 63 97 22 0.1 2.0 32 30.3 9 68 97 22 0.1 2.0 32 27.8 10 73 97 22 0.1 2.0 32 20.7

<1 liter of distilled water>

FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and NiCl ₂ · 6H ₂ O (Nickel Chloride) solution Example FeSO ₄ 7H ₂ O (g) NiCl ₂ · 6H ₂ O (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) 11 36 97 22 0.1 2.0 32 50.6 12 40 97 22 0.1 2.0 32 45.1 13 43 97 22 0.1 2.0 32 42.4 14 45 97 22 0.1 2.0 32 40.0 15 50 97 22 0.1 2.0 32 36.6 16 58 97 22 0.1 2.0 32 31.4 17 70 97 22 0.1 2.0 32 19.8

<1 liter of distilled water>

FeCl ₂ · 4H ₂ O (Ferrous Chloride) and NiSO ₄ · 6H ₂ O (Nickel Sulfate) solution Example FeCl ₂ · 4H ₂ O (g) NiSO ₄ · 6H ₂ O (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) 18 30 97 22 0.1 2.0 32 49.2 19 36 97 22 0.1 2.0 32 43.0 20 42 97 22 0.1 2.0 32 37.5 21 44 97 22 0.1 2.0 32 36.2 22 52 97 22 0.1 2.0 32 30.1 23 70 97 22 0.1 2.0 32 21.0

<1 liter of distilled water>

Use FeCl ₂ · 4H ₂ O (Ferrous Chloride) and NiCl ₂ · 6H ₂ O (Nickel Chloride) solution Example FeCl ₂ 4H ₂ O (g NiCl ₂ · 6H ₂ O (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) 24 34 97 22 0.1 2.0 32 48.7 25 40 97 22 0.1 2.0 32 41.9 26 44 97 22 0.1 2.0 32 38.3 27 46 97 22 0.1 2.0 32 36.2 28 50 97 22 0.1 2.0 32 32.7 29 65 97 22 0.1 2.0 32 21.8

FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) solution Example FeSO ₄ 7H ₂ O (g) Ni (NH ₂ SO ₃ ) ₂ (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) 30 25 97 22 0.1 2.0 32 49.5 31 28 97 22 0.1 2.0 32 44.8 32 35 97 22 0.1 2.0 32 36.3 33 37 97 22 0.1 2.0 32 34.5 34 45 97 22 0.1 2.0 32 27.4 35 52 97 22 0.1 2.0 32 22.1

<1 liter of distilled water>

Using FeCl ₂ · 4H ₂ O (Ferrous Chloride) and Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) solution Example FeSO ₄ 7H ₂ O (g) Ni (NH ₂ SO ₃ ) ₂ (g) Boric acid (g) Sodium lauryl sulfate Saccharin (g) Sodium chloride (g) Composition of plating (molding) material (wt% Ni) 36 22 97 22 0.1 2.0 32 50.2 37 26 97 25 0.1 2.0 32 44.0 38 32 97 25 0.1 2.0 32 37.0 39 34 97 25 0.1 2.0 32 35.2 40 42 97 25 0.1 2.0 32 28 41 52 97 25 0.1 2.0 32 20.4

<1 liter of distilled water>

Table 1 shows that FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and NiSO ₄ · 6H ₂ O (Nickel Sulfate) were used as the main components of the plating (molding) solution, and the amount of Nickel Sulfate was kept constant at 97 g / l. While changing the amount of ferrous sulfate in the range of 28 to 73 g / l, Fe-Ni alloys having the desired compositions were shown in (Examples 1 to 10).

<Table 2> shows FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and NiCl ₂ · 6H ₂ O (Nickel Chloride) as the main components of the plating (molding) solution, keeping the amount of Nickel Chloride constant at 97g / l While changing the amount of Ferrous Sulfate in the range of 36 to 70 g / l, Fe-Ni alloys having the desired compositions were shown in (Examples 11 to 17).

<Table 3> shows FeCl ₂ · 4H ₂ O (Ferrous Chloride) and NiSO ₄ · 6H ₂ O (Nickel Sulfate) as the main components of the plating (molding) solution, and the amount of Nickel Sulfate was kept constant at 97 g / l. While the amount of Ferrous Chloride was varied in the range of 30 to 70 g / l, Fe-Ni alloys having a desired composition were shown in (Examples 18 to 23).

<Table 4> shows FeCl ₂ · 4H ₂ O (Ferrous Chloride) and NiCl ₂ · 6H ₂ O (Nickel Chloride) as the main components of the plating (molding) solution, and the amount of Nickel Chloride is kept constant at 97 g / l. The Ferrous Chloride content was varied in the range of 34 to 65 g / l to produce Fe-Ni alloys of the desired compositions.

<Table 5> shows FeSO ₄ · 7H ₂ O (Ferrous Sulfate) and Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) as the main components of the plating (molding) solution, and the amount of Nickel Sulfamate was constant at 97g / l. The results of preparing the Fe-Ni alloy having the desired composition by varying the amount of Ferrous Sulfate in the range of 25 to 52 g / l while maintaining it were shown in (Examples 30 to 35).

<Table 6> shows the use of FeCl ₂ · 4H ₂ O (Ferrous Chloride) and Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) as the main components of the plating (molding) solution, and the amount of Nickel Sulfamate was constant at 97g / l. The results of producing the Fe-Ni alloy of the desired composition by varying the amount of Ferrous Chloride in the range of 22 to 52 g / l while maintaining it were shown in (Examples 36 to 41).

Although the apparatus for manufacturing the Fe-Ni alloy of a desired composition using the above-mentioned electrolyte solution of this invention is not specifically limited, To manufacture the Ni alloy thin plate of (Examples 1-41) shown to Tables 1-6. In order to manufacture and use the batch type electroplating (molding) apparatus of <Figure 1>. In FIG. 1, the electrolytic solution 3 invented in the present study was placed in the electrolytic cell 9, and the electrolyte solution flowed between the negative electrode 1 and the positive electrode 2 having a distance of 10 mm at a flow rate of 0.1 to 2.0 m / sec. The electroplating (molding) was performed while operating the circulation pump 5 to flow. When the 20-μm-thick Fe-Ni alloy was electrodeposited on the cathode, the current supply device 4 was stopped, and then a plating (molding) material was separated from the cathode surface to obtain a thin plate. In this device, the cathode material is characterized by varying the inclination angle 10 according to the flow rate.

The Fe-Ni alloy produced by the above-described method showed a coefficient of thermal expansion in the range of 1 to 9 µm / m · K only depending on the alloy composition, regardless of the type of electrolyte solution shown in Tables 1 to 6. Table 7 shows the values of the coefficients of thermal expansion obtained using the thermal expansion measuring apparatus for some examples. Compared with the commercially available bar alloy having a thermal expansion coefficient of 1.2 to 1.5 μm / m · K in the same temperature range, it can be said that the invar alloy sheet according to the present invention exhibits excellent low thermal expansion characteristics.

Table 7 Thermal Fluctuation Coefficient of Fe-Ni Alloy Prepared in the Present Invention (50 ~ 100 ° C)

Example Thermal expansion coefficient (μm / mK) One 9.01 2 8.12 3 6.23 4 2.99 5 1.58 6 2.21 7 4.25 8 8.30

Another feature of the Fe-Ni alloy according to the present invention is that it is a nanocrystalline structure having 5 to 15 nm of grains constituting it. As a result of calculating the size distribution of the grains according to the alloy composition using X-ray diffraction, the grain size of the invar alloy composition was found to be the smallest in the range of 5-7 nm. In the case of the nanocrystalline structure, the yield strength is about 2,000 MPa, which is much larger than the yield strength of the Invar alloy according to the conventional method, 260 to 500 MPa. Application is possible.

The Fe-Ni alloy with low thermal expansion properties can be manufactured by a single-step electroforming method, which greatly reduces the manufacturing cost. In particular, by having a nanocrystalline structure, the mechanical properties are excellent, thereby creating a new range of industrial applications. have.

Claims (8)

25 to 73 g of FeSO ₄ · 7H ₂ O (Ferrous Sulfate) or FeCl ₂ · 4H ₂ O (Ferrous Chloride) or mixtures thereof, 97 g of NiSO ₄ · 6H ₂ O (Nickel Sulfate) or NiCl ₂ per liter of water 6H ₂ O (Nickel Chloride) or Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate) or mixtures thereof, 20-30 g of boric acid (H ₃ BO ₃ , Boric acid), saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) _{1 to} 3g, Sodium Lauryl Sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 ~ 0.3g, Sodium chloride (NaCl, Sodium Chloride) Fe-Ni alloy characterized in that it contains Electrolytic solution for preparing the. According to claim 1, 28 to 73 g of FeSO ₄ · 7H ₂ O (Ferrous Sulfate), 97 g of NiSO ₄ · 6H ₂ O (Nickel Sulfate), boric acid (H ₃ BO ₃ , Boric acid) per 20 liters of water 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) 20 An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises -40g. According to claim 1, per 1 liter of water, 36 to 70g of FeCl ₂ · 4H ₂ O (Ferrous Chloride), 97g NiCl ₂ · 6H ₂ O (Nickel Chloride), Boric acid (H ₃ BO ₃ , Boric acid) 20 _~ 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) 20 An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises -40g. 30 to 70 g of FeSO ₄ · 7H ₂ O (Ferrous Sulfate), 97 g of NiSO ₄ · 6H ₂ O (Nickel Sulfate), boric acid (H ₃ BO ₃ , Boric acid) 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) 20 An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises -40g. According to claim 1, per 1 liter of water, 34 to 65g FeCl ₂ · 4H ₂ O (Ferrous Chloride), 97g NiCl ₂ · 6H ₂ O (Nickel Chloride), Boric acid (H ₃ BO ₃ , Boric acid) 20 to 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) 20 An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises -40g. The method of claim 1, wherein, per liter of water, 30 to 35 g of FeSO ₄ 7H ₂ O (Ferrous Sulfate), 97 g of Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate), boric acid (H ₃ BO ₃ , Boric acid) 20 to 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises 20 to 40g. The method of claim 1, wherein 22 to 52 g of FeSO ₄ · 7H ₂ O (Ferrous Sulfate), 97 g of Ni (NH ₂ SO ₃ ) ₂ (Nickel Sulfamate), boric acid (H ₃ BO ₃ , Boric acid) 20 to 30 g, saccharin (C ₇ H ₄ NO ₃ SNa, Sodium Saccharin) 1.0 to 3.0 g, sodium lauryl sulfate (C ₁₂ H ₂₅ O ₄ SNa, Sodium Lauryl Sulfate) 0.1 to 0.3 g, sodium chloride (NaCl, Sodium Chloride) An electrolyte solution for producing a Fe-Ni alloy, characterized in that it comprises 20 to 40g. The electrolyte solution according to claim 1, wherein the pH of the electrolyte is 2-4, the current density is 50-100 mA / cm ² , and the temperature of the electrolyte is 50-60 ° C. 11. .