JPH04293765A - Titanium carbide coated parts - Google Patents

Abstract

PURPOSE:To provide titanium carbide coated parts having superior corrosion and wear resistances and usable over a long period of time. CONSTITUTION:Ti is allowed to penetrate into the surface layer 6C of iron as the base material of parts 6 by diffusion and a titanium carbide coating film is formed to obtain titanium carbide coated parts (agitating blades) 6.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to parts coated with titanium carbide, which have excellent corrosion and wear resistance and are suitable for use in environments prone to corrosion and wear.

0002

[Prior Art] Conventional parts used in environments prone to corrosion and wear include, for example, the Japanese Utility Model Publication No. 60-1495
There is a submersible sand pump described in Publication No. 3. As shown in FIGS. 4 and 5, the submersible sand pump described in this publication includes a pump casing 2 supported by a support 1 on the bottom of the water, and a porous hole interposed between the pump casing 2 and the support 1. A cylindrical strainer 3, an impeller 5 attached to a drive shaft 4 of a motor (not shown) built into the pump casing 2, and an impeller 5 attached to the lower end of the drive shaft 4 located below the impeller 5. The support body 1 includes a disturbance blade 6 that disturbs water within the support body 1.

The strainer 3 has a porous horizontal end plate 3A at its lower end, and this horizontal end plate 3A has an opening through which the stirring blade 6 can pass. Further, as shown in FIG. 5, the disturbance blade 6 includes a plurality of blades 6A formed on the lower side thereof, and a connecting boss 6B connected to the drive shaft 4. Since the stirring blade 6 is used under severe conditions, its surface is plated with hard chrome.

Next, the operation of the submersible sand pump will be explained. When the motor of the submersible sand pump is driven, the impeller 5 and the stirring blades 6 rotate through the drive shaft 4, causing water to flow in the direction indicated by the arrow in FIG. It stirs up sediment from the bottom of the water. Next, the water containing earth and sand is sucked by the impeller 5 and the water containing earth and sand is discharged.

[0005]

[Problem to be Solved by the Invention] However, in items such as submersible sand pumps, which are subject to severe usage conditions, parts such as the stirring blade 6, which are subject to severe corrosion and wear due to sand and sand, are plated with hard chrome. Such parts have uneven surfaces, making it difficult to apply uniform chrome plating, and the thickness of the chrome plating is particularly thick on the convex parts marked with an ○ in Figure 5, and conversely on the concave parts marked with an x. The problem was that the thickness of the chrome plating was very thin, and corrosion progressed faster in the thin recesses of the chrome plating than in other parts, resulting in a short life. In addition, hard chrome plating has a low micro-Vickers hardness (mHv) of 770 and has a problem of poor wear resistance.

[0006] Therefore, the present invention was made to solve the above problems, and provides a titanium carbide coated part that has excellent corrosion resistance and wear resistance and can be used for a long period of time. It is intended to.

[0007]

[Means for Solving the Problems] The parts of the present invention are made of iron as a base material, and titanium is diffused and permeated into the surface layer of the base material to form a titanium carbide coating.

[0008]

[Function] According to the present invention, even when used in an environment where corrosion and abrasion are likely to occur, since the surface is coated with titanium carbide, it is resistant to corrosion and abrasion and can be used for a long period of time.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in FIGS. 1 and 2, with the same or corresponding parts as those of the prior art being designated by the same reference numerals. In each figure, FIG. 1 is a perspective view showing a stirring blade used in a submersible sand pump which is an embodiment of the present invention;
FIG. 2 is a sectional view showing a state in which the stirring blade shown in FIG. 1 is suitably treated with titanium carbide, and FIG. 3 is a graph showing the relationship between hardness and wear resistance.

The stirring blade 6, which is a component of this embodiment, is formed using iron as a base material, and as shown in FIG. It is equipped with a boss 6B. As described later, the iron material forming the stirring blade 6 only needs to contain carbon that can produce titanium carbide when treated with titanium powder, and normally, a material containing about 1% by weight of carbon can produce titanium carbide. preferred for production.

Next, a preferred method for treating the above-mentioned stirring blade 6 with titanium carbide will be explained with reference to FIG. To carry out this treatment, first, the appearance of the stirring blade 6 is inspected, and then the stirring blade 6 that passes these inspections is subjected to pre-treatments such as degreasing, pickling, and blasting.

Before treating the stirring blade 6 with the treatment agent 10, the threaded portion of the boss 6B of the stirring blade 6 is filled with a filler 11, and the opening of the boss 6B is closed with a lid 12, and further, The lid 12 is fixed to the boss 6B with bolts 13 to prevent the processing agent 10 from entering into the threaded portion from the opening.

Thereafter, the pre-treated disturbance blade 6 is stored in a processing box 14 made of a body plate together with a processing agent 10 containing titanium, and the disturbance blade 6 is placed in the processing agent 10 as shown in FIG. After being buried, the processing box 14 is covered with a lid to make it semi-sealed. Subsequently, the processing gas G is introduced into the processing box 14 from the introduction pipe 15 attached to the side surface of the processing box 14, and the introduced processing gas G is led out from the outlet pipe 16, and this state is maintained at a predetermined temperature at a predetermined temperature. The disturbance blade 6 is treated with the treatment agent 10 for a certain period of time. Through such treatment, treatment agent 1
Titanium contained in 0 diffuses into the surface layer 6C of the disturbance blade 6,
It penetrates and combines with carbon contained in the surface layer 6C to generate titanium carbide, forming a titanium carbide coating on the surface of the stirring blade 6. At this time, the test piece is buried in the treatment agent 10 and subjected to the same treatment as the stirring blade 6.

After completing the above surface treatment, the processing box 14 is opened, the disturbance blade 6 and the test piece are taken out from the processing agent 10, each is brushed to remove the processing agent 10 adhering to its surface, and then washed with water. ,dry. The quality of the titanium carbide treatment is determined by a test piece, and if the coating is in good condition, it is determined that the titanium carbide coating of the stirring blade 6 is also good and shipped.

[0015]The processing agent 10 is preferably one containing titanium powder as a main ingredient, and consisting of alumina powder, ammonium chloride powder, potassium fluoroborate powder, and a small amount of iron powder. Furthermore, as the processing gas G, a reducing gas such as hydrogen gas or an inert gas such as argon is preferably used. In addition, the treatment temperature and treatment time are usually 900 to 1100°C, 1
About 0 hours is preferable.

In the stirring blade 6 obtained by the above-described treatment, the thickness of the surface layer 6C made of a titanium carbide film is usually about 20 to 30 μm. Furthermore, as shown by the arrow in Fig. 3, the hardness of the surface layer 6C is approximately 2,800 to 3,500 micro Vickers hardness (mHv), while that of the hard chrome plating film is extremely low at 770. . In addition, this figure 3 shows the relationship between the amount of wear and hardness described in "Corrosion and Ecorosion" (published by the Corrosion Prevention Association, Shokabo). and a hard chrome plating film.

Therefore, since the surface of the stirring blade 6 of this embodiment is coated with titanium carbide, it has excellent corrosion resistance and wear resistance, and this titanium carbide coating also penetrates into the titanium surface layer 6C. Because it is formed so that it will not peel off due to diffusion and penetration, its lifespan is extremely long compared to plating, painting, etc.

In the above embodiment, the present invention was only applied to the stirring blade 6 of a submersible sand pump, but the present invention is not limited to the above embodiment in any way, and the invention is not limited to the above embodiment. Parts used in harsh environments, such as submersible sand pump impellers, supports,
It goes without saying that the present invention can also be applied to parts such as axial flow turbine blades, blower fans, pumps, air transport pipes, and acid slurry transport pipes, which are affected by powder particles.

[0019]

As described above, according to the present invention, it is possible to provide a titanium carbide coated part that has excellent corrosion resistance and wear resistance and can be used for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a stirring blade used in a submersible sand pump according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a state in which the stirring blade shown in FIG. 1 is subjected to a suitable titanium carbide treatment.

FIG. 3 is a graph showing the relationship between hardness and wear resistance.

FIG. 4 is a sectional view showing a part of a conventional submersible sand pump.

FIG. 5 is a perspective view of the stirring blade of the submersible sand pump shown in FIG. 4, illustrating non-uniform plating of the stirring blade.

[Explanation of symbols]

6 Disturbing blade (parts)

Claims (1)

[Claims] 1. A part whose base material is iron, characterized in that a titanium carbide coating is formed by diffusing and penetrating titanium into the surface layer of the base material.