KR200431577Y1 - Rolling roller with ceramic tip - Google Patents

Abstract

The present invention relates to a rolling roller having a ceramic tip, the process of mixing 98 ~ 99.5% of zirconia and 0.5 ~ 2% of alumina, the process of performing a general spray drying to the mixture of zirconia and alumina by the composition ratio, and the mixture Pressing by a CIP method, but the process of processing into a molded body under the conditions of 1.5 ~ 2ton / cm ² , the process of the first sintering the CIP processed molded body at a temperature condition of 1600 ~ 1650 ℃, and the first sintering treatment Disclosed is a technique for a rolling roller having a ceramic tip manufactured by a secondary sintering process of a molded product, and a process of making a ceramic sintered body by HIP sintering at a temperature of 1600 to 1650 ° C., a gas atmosphere of Ar, and a pressure of 1500 atm.

According to the present invention, it is possible to exert excellent mechanical and chemical stability properties and to remove chemical reactions generated by the use of tungsten-cobalt cemented carbide, as well as low friction coefficient, high wear resistance, high toughness and high strength. It can improve the rolling efficiency and extend the service life by the characteristics, it does not occur the same work and process loss as the existing, as well as improve the productivity and provide ease of maintenance.

Description

Rolling roller with ceramic tip {ROLLING ROLLER WITH CERAMIC TIP}

1 is a cross-sectional view showing a rolling roller having a ceramic tip according to the present invention.

2 is a process chart showing a manufacturing process of the ceramic tip according to the present invention.

Explanation of symbols on the main parts of the drawings

100: rolling roller 110: rod

120: ceramic tip 130: stopper

140: cover

The present invention relates to a rolling roller, and more particularly, to a rolling roller having a ceramic tip providing a roll tip of a ceramic sintered body having a low coefficient of friction, high wear resistance and durability.

In general, in the production of various wire rods such as copper wires, rebar or metal plate materials, the rolling process is carried out to produce a product having a certain shape and thickness by pushing the material between the rotating rolling rollers. Rolling is performed by a roll tip of a provided ring structure.

In this case, a rolled tip made of cemented carbide is usually used for the rolling roller used for the production of wire rods, such as copper wire. As the roll tip, a tungsten (WC) -cobalt (Co) -based alloy having good mechanical properties and very high rigidity is used. have.

Here, cobalt (Co) is used as a binder to bind tungsten (WC) carbide, and cobalt having a low melting point (1480 ° C) cannot be derived because it cannot derive its own binding force of tungsten having a high melting point of 3410 ° C. It is intended to induce bonding between tungsten carbide at low melting point.

However, cobalt (Co) used for bonding between tungsten (WC) carbides in the production of wires such as copper wire through a rolling roller having a roll tip made of tungsten (WC) -cobalt (Co) cemented carbide is copper of copper ( As a result of chemical reactions in contact with Cu), cobalt is released from the surface.

As a result, the bonding force of tungsten carbide is lowered and the damage from the surface of the roll tip causes a problem that the surface of the roll tip needs to be polished and the service life is shortened. As a result of the combined work and process loss occurs, as well as the productivity is lowered, the inconvenience that must always be provided with an extra roll tip or rolling roller was followed.

The present invention was created in view of the above problems, and its object is to provide a roll tip of a ceramic sintered body having excellent mechanical properties such as low coefficient of friction, high wear resistance and durability, and to improve rolling efficiency. It is to provide a rolling roller having a ceramic tip that can extend the service life and improve the productivity.

Rolling roller having a ceramic tip of the present invention for achieving the above object is characterized in that in the rolling roller for the rolling treatment, a ceramic tip consisting of a mixture of zirconia and alumina is coupled to the tip of the rod to be the main body .

At this time, the ceramic tip is characterized in that the ceramic sintered body consisting of zirconia 98 ~ 99.5% and alumina 0.5 ~ 2%.

The ceramic tip is spray-dried to a mixture of 98 to 99.5% of zirconia and 0.5 to 2% of alumina, and processed into a molded body by CIP pressing at a condition of 1.5 to 2 ton / cm ² . After the first sintering is characterized in that the ceramic sintered body produced by performing the second HIP sintering at a temperature of 1600 ~ 1650 ℃ and the gas atmosphere of Ar and 1500 atm.

Hereinafter, with reference to the accompanying drawings and a preferred embodiment of the present invention will be described in detail.

1 is a cross-sectional view showing a rolling roller having a ceramic tip according to the present invention, Figure 2 is a process chart showing a manufacturing process of the ceramic tip according to the present invention.

As shown in Figure 1, the rolling roller 100 having a ceramic tip according to the present invention is a rod 110, which is a main body, and the stopper is inserted into the outer side of the rod 110 is disposed in the center and disposed on both sides 130 and a ring-shaped ceramic tip 120 fixedly coupled to the rod 110 while being supported by the cover 140.

The coolant supply hole 111 may be formed in the rod 110 such that the coolant is supplied / circulated.

The ceramic tip 120 is composed of a ceramic sintered body which is a body made of a mixed structure of zirconia (ZrO 2) and alumina (aluminum oxide), but sintered.

That is, the ceramic tip 120 is formed by processing a mixture of zirconia and alumina into a molded body by pressing, followed by primary sintering and secondary hot isostatic pressing (HIP) sintering.

In this case, the ceramic tip 120 is composed of a mixture of 98 ~ 99.5% zirconia and 0.5 ~ 2% alumina.

In addition, referring to Figure 2, looking at the manufacturing process of the ceramic tip applied to the present invention in detail as follows.

First, zirconia and alumina are weighed at a composition ratio of 98 to 99.5% and 0.5 to 2%, respectively, and mixed to form a mixed composition (S1). At this time, the mixing of zirconia and alumina is ball milling.

Here, the zirconia is a stabilized oxide as a material having a high refractive index and a high melting point and having a high corrosion resistance and thermal shock resistance, and the alumina is hard and abrasion resistant, and has a material having excellent basic properties such as heat resistance, corrosion resistance, and precision processing. to be.

General spray drying is performed on the mixture of zirconia and alumina so that the synthesis and uniform powder of the powders for these mixtures can be formed (S2). At this time, the tissue density of the mixture is uniformly formed by spray drying.

The spray-dried mixture is pressed into a CIP (Cold Isostatic Press) method and processed into a primary molded product (S3). At this time, the pressure condition is 1.5 ~ 2ton / cm ² .

The CIP-processed molded body is first sintered at a temperature of 1600-1650 ° C. (S4). At this time, the alumina in the mixture is a sintered material to act to induce the inter-bond bonding force of the zirconia and the inter-particle bonding force of the zirconia and alumina.

The first sintered molded body is subjected to a second sintering process, and a HIP (hot isostatic pressing) sintering process to prepare a ceramic tip with a ceramic sintered body (S5). At this time, during the sintering of HIP, sintering is performed under conditions of a temperature of 1600 to 1650 ° C., a gas atmosphere of Ar, and 1500 atm.

Here, HIP sintering under the above conditions serves to remove pores in the tissue formed in the zirconia and alumina mixture to remove pores from the finished ceramic tip.

Accordingly, the ceramic tip consisting of a mixed composition of zirconia and alumina forms a very strong bonding force between the tissues to exhibit high toughness, high strength and durability, as well as having a low coefficient of friction and high wear resistance.

In addition, the rolling roller having the ceramic tip 120 as shown in FIG. 1 is subjected to surface processing of grinding and polishing in the state where the ceramic tip 120 of the sintered body thus manufactured is assembled at the tip of the rod 110 which is the main body. 100).

In addition, Table 1 below shows the physical properties of the ceramic tip of the ceramic sintered body according to the present invention.

Mechanical properties unit Data value density g / cm ³ 6.05 Hardness HV 1250 Bending strength MPa 900 Compressive strength MPa 2500 Fracture toughness MPa.m ^1/2 6 Granularity Μm One Chemical stability Acid (HCL) stability Alkali (KOH) stability

As shown in Table 1, it can be seen that the ceramic tip of the present invention exhibits excellent mechanical properties such as density and hardness, bending strength, compressive strength and fracture toughness, and the ceramic tip of the present invention is acid (HCL). It is also very stable in chemical stability through alkali and alkali (KOH).

Therefore, the ceramic tip according to the present invention can not only increase the rolling efficiency due to the low coefficient of friction, high wear resistance, high toughness and high strength, but also extend the service life and improve productivity.

On the other hand, the rolling roller having a ceramic tip according to the present invention has been described with reference to the specific embodiments and the accompanying drawings as described above, but is not particularly limited thereto, the similar category of the technical idea for the claims of the present invention Various modifications made within will be attributed to the present invention.

As described above, according to the method of manufacturing a rolling roller and a ceramic tip having a ceramic tip according to the present invention, it is possible to exhibit excellent mechanical properties and chemical stability, and a chemical reaction phenomenon generated when using cemented carbide using tungsten-cobalt. Not only can it eliminate the problem, but the low coefficient of friction, high wear resistance, high toughness and high strength can improve rolling efficiency, extend the service life, prevent the loss of work and process as well as improve productivity. This can be done and provides ease of maintenance.

Claims (3)

In constructing a rolling roller for rolling treatment, A rolling roller having a ceramic tip, characterized by combining a ceramic tip composed of a mixture of zirconia and alumina at the tip of a rod which becomes a main body. The method of claim 1, The ceramic tip is a rolling roller having a ceramic tip, characterized in that the ceramic sintered body consisting of zirconia 98 ~ 99.5% and alumina 0.5 ~ 2%. The method of claim 1, The ceramic tip is spray-dried to a mixture of 98 to 99.5% of zirconia and 0.5 to 2% of alumina, and processed into a molded body by CIP pressing at a condition of 1.5 to 2 ton / cm ² . Rolling roller having a ceramic tip, characterized in that the first sintered ceramic sintered body produced by the second HIP sintering at a temperature of 1600 ~ 1650 ℃ and the gas atmosphere of Ar and 1500 atm.

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