KR20030039708A - Ni-w/mo/lanthanide mixed-rare earth metal electroless plating solution and plating method using the same - Google Patents

Abstract

PURPOSE: Ni-W/Mo/Lanthanide mixed-rare earth metal electroless plating solution and a plating method using the same are provided. CONSTITUTION: The Ni-W/Mo/Lanthanide mixed-rare earth metal electroless plating solution contains, in 1 liter of distilled water, nickel sulfate 5 to 15g, sodium tungstate 20 to 35g, molybdenum 25 to 35g, Lanthanide mixed-rare earth metal 0.1 to 5g, sodium citrate 10 to 15g, sodium hypophosphate 5 to 10g and molybdenum ionic surfactant 0.7 to 2.0g/25cc, wherein the ionic surfactant is dioctyl phthalate+phthyl cellosolve; the diameter is molybdenum is 0.1 to 1.0 micrometer; the diameter of Lanthanide mixed-rare earth metal is 0.1 to 2.3 micrometer. The plating method using Ni-W/Mo/Lanthanide mixed-rare earth metal electroless plating solution includes the steps of completely dissolving nickel sulfate 5 to 15g, sodium tungstate 20 to 35g in 1 liter of distilled water; secondary dissolving sodium citrate 10 to 15g, sodium hypophosphate 5 to 10g in the distilled water; adding 25 to 35g of molybdenum with a particle size of 0.1 to 1.0 micrometer, 0.1 to 5g of Lanthanide mixed-rare earth metal with a particle size of 0.1 to 2.3 micrometer and 0.7 to 2.0g/25cc of molybdenum ionic surfactant in the distilled water; electroplating a specimen to be plated in a thickness of 7 to 10 micrometers at pH 9.0 to 9.8 at electroplating solution temperature of 85 to 90°C; and heat treatment at 350 to 450°C for about 30 min.

Description

Ni-W / Mo / Lanthanide mixed-rare earth metal electroless plating solution and plating method using the same}

The present invention relates to an electroless Ni-W / Mo / lanthanum-based mixed rare earth metal plating solution and a plating method using the same. More specifically, an ionic surfactant is used as a stabilizer for an electroless plating solution, and a reducing agent and a complexing agent suitable therefor. Select to provide a plating solution that can electrolessly plate tungsten, molybdenum and lanthanum mixed rare earth metals in combination, and surface treatment after electroless composite plating to increase wear resistance, hardness and ductility of primary plated products. And finally heat treated at about 350 to 450 ° C. for about 30 minutes or more to provide a highly wear resistant and high hardness product of Hv 2,850 to 3,200 as a Vickers hardness tester. Electroless Ni-W / Mo / lanthanum mixed rare earths It relates to a metal plating solution and a plating method using the same.

Referring to FIG. 1, in general, electroless plating refers to a plating target when the object to be plated 1 is brought into contact with a solution in which a plating solution (or a metal salt 5) and a soluble reducing agent 3 coexist in a plating bath 4. A method of forming the plating material (2) on the surface of the object (1), the electrons released by the oxidation of the reducing agent (3) is transferred to the metal ions to form a metal film is a non-electrical plating is called electroless plating. do.

As described above, the electroless plating technique is a method in which metal ions in an aqueous metal salt solution are reduced to metal molecules to be deposited on the surface of an object to be processed without receiving electrical energy from the outside. Plating can be performed in a thickness of about 25 μm. To date, electroless plating is made of copper (Cu), nickel-phosphorus (Ni-P), nickel-cobalt (Ni-Co), nickel-boron (Ni-B) and nickel-tungsten-phosphorus (Ni-WP) alloys. It could be applied to various substrates such as plastics and organic materials as well as conductor metals.

As a related art, Korean Patent Laid-Open Publication No. 2000-76067 discloses a method of metal plating by electroless plating on a surface having a low conductivity, a mirror surface or a powder, and a metal plating pretreatment therefor. Korean Patent Laid-Open Publication No. 97-701275 discloses an electroless plating pretreatment liquid, an electroless plating bath and an electroless plating method formed on a metal film containing a basic compound, a reducing agent and a complexing agent. In addition, Korean Patent Application Publication No. 83-07893 discloses a plating solution in which 80g of nickel sulfate, 1,000g of sodium phosphate, 24g of sodium acetate, 12g of sodium acetate, 8g of boric acid, and 6g of ammonium chloride are mixed and prepared, and Korean Patent Application No. 97 -77682 discloses a method of plating a steel can and cap onto a steel can and cap by using an electroless plating method, in which a W (tungsten) vacancy is coated in a Ni-P (nickel-phosphorus) alloy having a relatively high P content.

However, conventionally, the plating using various metals is not performed due to the limitation of the plating material, the reducing agent, and the stabilizer. Therefore, there is a limitation in the surface treatment of materials having high wear resistance or ductility and strength.

Therefore, the present invention has developed a technology for complex electroless plating of tungsten, molybdenum and lanthanum mixed rare earth metals by using an ionic surfactant as a stabilizer of an electroless plating solution, and selecting a reducing agent and a complexing agent suitable for this. The present invention has been completed based on this.

Accordingly, it is an object of the present invention to provide an electroless Ni-W / Mo / lanthanum-based mixed rare earth metal plating solution which can increase the hardness, strength, ductility and wear resistance of the plated surface.

Another object of the present invention is to provide a method for plating a plated object using the plating solution.

The electroless Ni-W / Mo / lanthanum mixed rare earth metal plating solution of the present invention for achieving the above object is 5 to 15 g of nickel sulfate, 20 to 35 g of tungsten sodium, 25 to 35 g of molybdenum, and lanthanum mixed rare earth metal with respect to 1 L of distilled water. 0.1-5g, 10-15g sodium citrate, 5-10g sodium hypophosphate, and 0.7-2.0g / 25cc molybdenum ion surfactant.

Plating method using the above plating solution to achieve another object of the present invention after filling the plating tank half with distilled water and completely dissolved by adding nickel sulfate 5-15g / l and tungsten sodium 20-35g / l, sodium citrate 10 After further dissolving ˜15 g / l and 5-10 g / l of sodium hypophosphate, 25 to 35 g / l of molybdenum having a particle size of 0.1 to 1.0 μm, and 0.1 to 5 g / l of lanthanum mixed rare earth metal having a particle size of 0.1 to 2.3 μm and molybdenum Adding 0.7 to 2.0 g / 25 cc of an ionic surfactant, and replenishing with distilled water to the plating bath level; Plating the object to be plated with a plating rate of 7 to 10 μm per hour by adjusting the plating bath temperature to 85 to 90 ° C. and a pH of the solution to 9.0 to 9.8; And surface-treating the object to be plated and heat-treated at 350 to 450 ° C. for at least about 30 minutes.

1 is a view schematically showing a plating mechanism in a conventional electroless plating process,

2 is a view schematically showing an apparatus suitable for applying the plating method according to the present invention.

※ Explanation of code about main part of drawing ※

1.Object to be plated 2. Plating material (M)

3. Reducing agent (R) 4. Plating bath

5. Plating solution 6. Air piping

7. Heating Heater 8. Thermostat

9. Automatic pH Control 10. air blower

Filter pump 12. Pre-plating bath

Looking at the present invention in more detail as follows.

As described above, the electroless plating technology has been mainly made of surface treatment technology using Cu, Ni-Co and Ni-P, so that many industries can make uniform surface treatment and surface treatment of non-metallic materials such as plastic trees. Was applied. However, one of the fields still to be solved, such as being restricted by plating materials, is to plate tungsten, molybdenum, and lanthanum mixed rare earth metals having excellent mechanical properties using an electroless method. Tungsten is often used as a nickel-tungsten-phosphorus alloy, but molybdenum and lanthanum mixed rare earth metals are rarely used as plating components. Therefore, what is required at this time is the development of important reducing agents and stabilizers in electroless plating.

Thus, in the present invention, a stable electroless plating was performed by using sodium citrate as a complexing agent of an electroless plating solution, a sodium phosphate solution as a reducing agent, and an ionic surfactant as a stabilizer. In addition, molybdenum and lanthanum mixed rare earth metals were added as the metal components to be plated to allow alloy plating for nickel-tungsten electroless plating, thereby increasing the hardness, strength, ductility, and wear resistance of the surface-treated part. It is shown up to Hv 3,200 by Brindel hardness tester.

As described above, the electroless Ni-W / Mo / lanthanum mixed rare earth metal plating solution of the present invention comprises nickel sulfate, tungsten sodium, molybdenum, lanthanum mixed rare earth metal, sodium citrate, sodium hypophosphite and molybdenum ionic surfactant do.

According to the present invention, 5 to 15 g of nickel sulfate is used for 1 L of distilled water, and 20 to 35 g of tungsten sodium is used. In addition, the molybdenum is used 25 ~ 35g per 1 liter of distilled water, if less than 25g toughness is weak, more than 35g may cause uniformity due to large residual stress, the particle size of the molybdenum is preferably 0.1 ~ 1.0㎛ This is for smooth electrodeposition. In addition, the amount of the lanthanum-based mixed rare earth metal is preferably 0.1 to 5 g with respect to 1 L of distilled water, and when the amount is less than 0.1 g, the effect of addition is insignificant. The particle diameter of the system-based mixed rare earth metal is preferably 0.1 to 2.3 占 퐉. However, if the particle diameter is less than 0.1 占 퐉, the electrodeposition rate is lowered.

Sodium citrate used as the complexing agent of the plating solution of the present invention is preferably used in 10 to 15g per 1L of distilled water, the metal powder (W, Ni) is electrodeposited in a certain ratio, sodium hypophosphate used as a reducing agent in 1L of distilled water It is preferable to use 5-10g with respect to stability of a plating liquid.

On the other hand, the ionic surfactant used as a stabilizer of the plating solution, which is a feature of the present invention, is used at 5.0 to 7.0 g per 1 L of distilled water, and when less than 5.0 g, the precipitation rate of the metal powder (molybdenum) decreases and exceeds 7.0 g. The plating solution tends to decompose. When the ionic surfactant is added to the plating solution, it is preferable to add it together with molybdenum, and the molybdenum ionic surfactant is composed of 0.7 to 2.0 g / 25 cc. The ionic surfactant usable in the present invention is diuktylphthalate + phthalocellosolve.

The addition of molybdenum ionic surfactant in an amount of 0.7 to 2.0 g / cc is most preferred because of the best electrodeposition of molybdenum metal on the metal surface at this concentration, and the amount of molybdenum at this time is different from that of molybdenum used for electroless plating. Is calculated.

On the other hand, the plating method of the present invention, first, with the distilled water, as shown in Figure 2, half of the plating tank (4) is added, and then completely dissolved by adding 5 to 15 g / l nickel sulfate and 20 to 35 g / l tungsten sodium Let's do it. Then, 10-15 g / l sodium citrate and 5-10 g / l sodium hypophosphate were further dissolved, followed by 25-35 g / l molybdenum having a particle size of 0.1-1.0 μm and a lanthanum mixed rare earth metal 0.1 having a particle size of 0.1-2.3 μm. -5 g / l and molybdenum ionic surfactant 0.7-2.0 g / 25 cc are added. After replenishing with distilled water to the level of the plating bath, the plating bath temperature is adjusted to 85 to 90 ° C. and the pH of the solution to 9.0 to 9.8 to plate the object to be plated at a thickness of 7 to 10 μm per hour. At this time, the reason for maintaining the plating rate at 7 to 10 탆 per hour is the average plating rate when the plating solution is used as a standard, and the plating rate is controlled by temperature, pH, and plating solution concentration. After plating, the surface of the object to be plated is subjected to heat treatment at 350 to 450 ° C. for about 30 minutes or more, preferably about 1 hour, thereby maintaining the hardness of the object to be Hv 2,850 to 3,200 using a Vickers hardness tester.

As described above, the present invention is a chemical reduction method electroless composite plating technology in which tungsten having high wear resistance and high hardness mechanical properties, molybdenum having high toughness, and a lanthanum mixed rare earth metal having a small amount of increased strength and ductility are added. As a surface treatment after plating, the hardness is maintained at about Hv 1,400 to 1,800 using a Vickers hardness tester. In addition, when finally heat-treated at about 350-450 degreeC for about 30 minutes or more, a Vickers hardness tester shows Hv 2,850-3,200.

Therefore, the electroless plating solution and plating method of the present invention is a high speed cutting blade in a large amount in the paper, fiber, film, glass wool / rock wool rubber industry, as well as precision mechanical parts, such as ultra-precision bearings that require wear resistance and high toughness, strength and hardness It can be applied to parts of semiconductor equipment. In this case, the base material of the parts requiring the wear resistance, hardness and strength is made of general mild steel with excellent mechanical properties and workability, and the price of parts is reduced when the electroless composite plating solution according to the present invention is plated only on the required surface. Of course, it is an excellent surface treatment technology that can significantly extend the use time.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following examples.

Example 1

In the present embodiment, as shown in Figure 2, the thermostat 8, the automatic pH regulator 9, the blower 10, the filter pump 11 and the pre-plating tank 12 is mounted on the outside And a plating bath 4 having an air pipe 6 and a heating heater 7 connected to the blower 10 therein was used.

The filter pump 11 filters the impurities, and the pre-plating tank 12 transfers and stores the plating solution to the pre-plating tank at the end of plating, and deposits air on the air pipe 6 to uniformly deposit the plating on the metal surface. Be sure to

After filling half of the plating bath (4) with distilled water, 11 g / l of nickel sulfate and 27 g / l of sodium tungsten were completely dissolved, and then 13 g / l of sodium citrate and 8 g / l of sodium hypophosphate were further dissolved, 30 g / l molybdenum (0.1-1.0 μm), 1 g / l lanthanum composite rare earth metal (0.1-2.3 μm) and 1 g / 25 cc molybdenum ionic surfactant were added and supplemented with distilled water to the plating bath level. The plating working conditions were about 87 ° C., and the pH of the plating bath solution was adjusted to 9.5 by adding NaOH to conduct a high speed cutting blade, which is a plated object, at a thickness of about 8 μm per hour for 1.5 hours. The Vickers hardness of this electroless composite plated blade was about Hv 1,600.

On the other hand, in order to increase the wear resistance, hardness and ductility of the electroless composite plated blade using the Ni-W / Mo / lanthanum-based rare metals, after the electroless composite plating, the surface treatment with rust-preventive oil, finally about 400 ℃ The final product was prepared by heat treatment at 1 hour. The Vickers hardness of this product was about Hv 3,000.

Wastewater does not occur because the plating liquid is used continuously while maintaining a constant concentration. VOCs, which are some air pollutants, are adsorbed and treated using activated carbon fibers to realize pollution-free plating technology.

Ni-W / Mo / lanthanum-based mixed rare earth metal electroless composite plating solution and plating method according to the present invention is a tungsten, molybdenum and lanthanum-based mixed rare earth in the excellent plating technology proved by conventional Cu, Ni-Co, Ni-P, etc. It is an excellent technology that dramatically improves mechanical properties by adding metal to surface treatment. In particular, the electroless plating used in the present invention is a technology that can be widely used in a special plating field in the future because it can be used continuously without generating plating wastewater which is difficult to treat.

In particular, the electroless plating solution developed in the present invention is capable of stable composite plating using tungsten and molybdenum, which have been difficult to use. In addition, the present invention is a composite plating technology that can add a lanthanum-based mixed rare earth metal in which the strength is increased by 10 to 20% and the ductility by about 10% even when only 0.1 to 0.3% by weight is added to the molten metal. Therefore, the electroless composite plating solution and plating method of the present invention are not only a variety of precision mechanical parts including ultra-precision bearings used in high precision aircraft and space shuttles that require abrasion resistance, high toughness, strength and hardness, but also paper, fiber, film, glass wool / rock wool It can be applied to high speed cutting blades and parts of semiconductor equipment used in a large amount in the rubber industry. In this case, when the base material of the parts requiring the wear resistance, hardness and strength is made of general mild steel having excellent mechanical properties and workability, the electroless composite plating of the present invention is used only on the required surface, of course, the lowering of the part price is used. It is an excellent environmentally friendly surface treatment technology that can significantly extend the time.

Claims (7)

Nickel sulfate 5-15g, sodium tungsten 20-35g, molybdenum 25-35g, lanthanum mixed rare earth metal 0.1-5g, sodium citrate 10-15g, sodium hypophosphite 5-10g and molybdenum ionic surfactant 0.7-2.0 per liter of distilled water An electroless Ni-W / Mo / lanthanum mixed rare earth metal plating solution, characterized in that it is composed of g / 25cc. The plating solution according to claim 1, wherein the ionic surfactant is diuktylphthalate + phthalyl cellosolve. The plating solution according to claim 1, wherein the molybdenum has a particle diameter of 0.1 to 1.0 mu m. The plating solution according to claim 1, wherein the lanthanum mixed rare earth metal has a particle diameter of 0.1 to 2.3 mu m. After half of the plating bath is filled with distilled water, 5 to 15 g / l of nickel sulfate and 20 to 35 g / l of tungsten sodium are completely dissolved. Then, 10 to 15 g / l of sodium citrate and 5 to 10 g / l of sodium hypophosphite are further dissolved. Then, 25 to 35 g / l molybdenum having a particle size of 0.1 to 1.0 µm, 0.1 to 5 g / l of a lanthanum mixed rare earth metal having a particle size of 0.1 to 2.3 µm, and 0.7 to 2.0 g / 25 cc of molybdenum ion surfactant were added thereto, followed by distilled water. Replenishing to the bath level; Plating the object to be plated with a plating rate of 7 to 10 μm per hour by adjusting the plating bath temperature to 85 to 90 ° C. and a pH of the solution to 9.0 to 9.8; And Surface treatment of the object to be plated and the plating method using an electroless Ni-W / Mo / lanthanum-based mixed rare earth metal plating solution comprising the step of heat treatment at 350 ~ 450 ℃ for more than about 30 minutes. The plating method according to claim 5, wherein the hardness after the surface treatment of the plated object is Hv 1,400 to 1,800 with a Vickers hardness tester. The plating method according to claim 5, wherein the hardness after the heat treatment step of the plated object is Hv 2,850 to 3,200 with a Vickers hardness tester.