KR20050065793A - Method for surface- hardening in the interior and exterior parts to austenite steel - Google Patents

Abstract

The present invention relates to a surface hardening method of stainless steel, and in particular, the surface of the austenitic steel after completion of the design of the interior and exterior parts is filled with a temperature of 570 ° C. to 580 ° C. for 120 minutes to 180 minutes. The product is made by polishing and polishing the nitride of internal and external parts that are slightly roughened, and the surface hardened parts maintain strength similar to tungsten products and corrosion resistance of stainless steel, and the color of the nitrided surface is dark black with high quality color. It can have various colors by dry plating to meet the demands of consumers, and there is no flaw or damage on the surface even after dry plating, and it is light in weight and has excellent economic and productivity effects.

Description

Surface hardening method of austenitic steel {Method for surface- hardening in the interior and exterior parts to austenite steel}

The present invention relates to a method of hardening the surface of stainless steel, and in particular, the surface of the austenitic steel after completion of the design of the internal and external parts is filled with a temperature of 570 ° C to 580 ° C for 120 minutes to 180 minutes. The present invention relates to a method for surface hardening of internal and external parts of austenitic steel, which is produced by polishing and polishing a nitride of internal and external parts in a slightly rough state.

In general, the interior and exterior parts act as important factors such as dimensional stability, practicality, appearance, and the like, and carbide materials such as stainless steel, brass, titanium, tungsten, or equivalent alloys of stellite are frequently used.

Here, stainless steel has very good workability and productivity, is not easily broken, has economical efficiency, and has a variety of designs, and has good qualification as general internal and external parts.

However, it is crucially weak in strength that its use is selective.

Tungsten steel is about 5 ~ 6 times stronger than stainless steel, and it does not cause any scratches, but it is relatively expensive, easily broken even by small impact, heavy weight, high unit production cost, and The drawback is that the design is simple.

Accordingly, the present invention is intended to reduce the above-mentioned drawbacks, nitrided internal and external parts of the finished stainless steel by nitriding the surface of the stainless steel in the temperature of 570 ℃ ~ 580 ℃ 120 minutes to 180 minutes to surface hardening nitride The purpose of the present invention is to provide a method of hardening the surface of internal and external parts of austenitic steel, which is a component of a.

Hereinafter, with reference to the accompanying drawings, the configuration and operation according to a preferred embodiment of the present invention will be described.

Surface hardening method of the internal and external parts of the stainless steel is characterized by utilizing the method of nitriding stainless steel to take advantage of the advantages and to compensate for the disadvantages.

Looking at the process of nitriding, first, the interior and exterior design of the stainless steel component is completed in a 570 ℃ ~ 580 ℃ nitriding furnace for 120 minutes to 180 minutes to fill.

The stainless steel used herein is austenitic steel, and can be used as a nitriding without particular limitation, the temperature of the nitriding furnace is preferably 570 ℃ ~ 580 ℃.

At this time, if the temperature is too high, there is a risk that the parts in the nitriding furnace are damaged. On the contrary, if the temperature is too low, a sufficient curing effect cannot be obtained.

At this temperature of the nitriding furnace, the filling time is suitably 120 minutes to 180 minutes.

If the filling time is shorter than the above time, the filling is not sufficient, on the contrary, if the time is too long, a stress corrosion cracking occurs and a hardening effect is not obtained.

After the predetermined nitriding filling process, nitride of internal and external parts having a slightly roughened surface is obtained, and internal and external parts having a dark black nitrided surface treatment are obtained by simple grinding.

On the other hand, by processing the dry plating on the interior and exterior parts completed through the above process, it is possible to meet the needs of various consumers by improving the appearance of the interior and exterior parts.

1 is a flow chart showing the surface hardening process step of the interior and exterior parts of austenitic steel according to the present invention.

First, degreasing is performed to remove surface contaminants of the target at 70 ℃ ~ 80 ℃, and then preheating process is performed for 10-20 minutes at 350 ℃ ± 10 ℃ to minimize the stress removal and temperature change of the target. Rough

Subsequently, the temperature of the furnace is controlled by adjusting the temperature between 570 ° C. and 580 ° C. within a time of 120 minutes to 180 minutes depending on the thickness of the object and the characteristics of the design.

After cooling the nitride generated according to the operation and removing the surface contamination source, the accurate surface hardness and the thickness of the nitride layer 10 are measured and inspected.

FIG. 2 is a flowchart illustrating a subsequent process step of FIG. 1, in which the nitride completed through the surface hardening process of FIG. 1 is polished, and the sludge 40 and the black layer 20 generated during cooling as shown in FIG. 4. Grind about 1/2 of 7-8u.

After the polishing is performed, the surface color of the nitride is dark black.

After performing the polishing and inspecting the surface color, a degreasing operation is performed to remove the surface contamination source of the nitride, and finally the surface roughness, surface color, and surface hardness of the nitride are examined.

3 is a flowchart illustrating a dry plating process step required by a consumer, and first, a degreasing operation is performed to remove a contaminant of nitride before dry plating.

Nitride, from which the pollutant is removed, is subjected to dry plating in accordance with CVD / PVD / IP.

The dry plated nitride is packaged after being inspected for corrosion resistance and correct color.

Figure 4 is a side view showing the measurement history of the surface hardening according to the present invention, the nitride (compound) layer 10 is 50 ~ 60u, wherein the white layer 30 is Cr carbide, the black layer 20 is Cr nitride 7 ~ 8u and the surface hardness is Hmv / 100g: 1200-1250).

That is, the internal and external parts of the finished stainless steel are filled in the nitriding furnace of 570 ° C. to 580 ° C. for 120 minutes to 180 minutes to harden the surface. When the nitriding treatment is performed, the surface hardness is Vickers hardness (Hmv / 100g: 1200 -1250).

The nitride shows a slightly roughened surface, which is polished on the inner and outer surfaces to give a smooth and best gloss.

Through the above process, the surface of stainless steel is obtained internal and external parts with nitrided surface treatment of about 50 ~ 60u thickness. At this time, the internal and external parts are light and have high quality of dark black. It does not occur and costs about one third of tungsten in terms of cost, namely economics.

As described above, the present invention has the same degree of hardness as tungsten products, has a high-quality color of dark black, and can diversify the color through dry plating to meet the demands of various consumers, and at the same time, scratches on the surface There is no damage, its own weight is also light, it has an excellent effect in economics and productivity.

Therefore, it can be expected to be used or applied in application-related fields such as tungsten and ceramics such as watch exterior products, interior and exterior products in electronic products, interiors and exteriors of automobiles, and accessories.

1 is a flow chart showing the process step of the surface hardening according to the present invention

2 is a flow chart showing the subsequent process steps of FIG.

Figure 3 is a flow chart showing the dry plating process step according to the request of the consumer

Figure 4 is a side view showing the measurement history of the surface hardening according to the present invention

Explanation of symbols on main parts of drawing

10: nitride (compound) layer 20: black layer (Cr nitride)

30: white layer (Cr carbide) 40: sludge

Claims (1)

Performing a degreasing operation to remove the pollutant of the object; Performing a preheating operation to minimize the stress of the target and change the temperature of the nitriding furnace; Adjusting the temperature and time of the nitriding furnace according to the thickness of the object and the characteristics of the design; Removing surface contaminants after cooling the object; Measuring the surface hardness and the thickness of the nitride layer; Grinding half of the sludge and the black layer generated during cooling of the measured nitride; Removing the surface contamination source of the polished nitride and inspecting the surface roughness, surface color and surface hardness of the nitride.