JPH06299318A - Method for finishing titanium ornament - Google Patents

Abstract

PURPOSE:To provide a method for finishing a titanium ornament by which an original finish and excellent wear resistance are ensured. CONSTITUTION:A titanium ornament is finished through a process for mirror- polishing the surface of the ornament, a process for nitriding the surface, a process for electrochemically removing a nitrided golden layer formed by nitriding and a process for carrying out semi-mirror finishing by barrel polishing. The titanium ornament is finished with original massiveness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for finishing ornaments made of titanium or titanium alloy.

[0002]

2. Description of the Related Art Most of conventional ornaments made of titanium or titanium alloy have a satin finish such as honing finish.

In addition, since a fingerprint or the like easily attaches to the matte finish skin to make it dirty, a transparent glass film coating of metal alkoxide or the like is applied to prevent dirt.

[0004]

The above-mentioned conventional titanium-made ornaments, therefore, can only finish products with a dark image of gray color tone, and for items such as ornaments where the richness of design is important. Was demanded to expand the finishing expression.

Further, the hardness of titanium material is generally Hv14.
There are only 0 to 170 positions, and there is a drawback that the surface finish is worn out because the environment such as a wristwatch is harsh especially when used for a long period of time, and the exterior of the wristwatch is harsh. The object of the present invention is to solve the above drawbacks,
It is an object of the present invention to provide a new finishing method and a finishing method for titanium ornaments having excellent wear resistance.

[0006]

Means for Solving the Problems The structure of the present invention for achieving the above-mentioned object is a step of shaping a decorative article such as a watch case, a band, a necklace, and glasses with titanium or a titanium alloy, A step of polishing the surface to a mirror finish, a step of nitriding the decorative article having the mirror finish, a step of electrochemically removing the gold nitride layer of the nitrided decorative article, and a step of removing the removed decorative article And a step of semi-mirror-finishing the surface by barrel polishing or the like.

[0007]

The details of the present invention will be described with reference to the following examples. In this embodiment, a wristwatch case that is a decorative item will be described. First, a JIS class 2 pure titanium material was prepared, and a wristwatch case blank was prepared by a generally-used manufacturing process, and was subjected to intermediate polishing and finish polishing to perform mirror finish. Next, this wristwatch case was heated to 850 ° C. and kept in an electric lamp filled with nitrogen gas for 20 hours for nitriding treatment. The surface of the wristwatch case that had been subjected to this nitriding treatment had a beautiful golden color of titanium nitride. However, this surface was slightly lacking in specular gloss due to recrystallization. After that, a wristwatch case was set on the anode side in an electrolytic solution containing hydrofluoric acid as a main component and immersion electrolysis was carried out for 5 to 10 seconds to remove the gold nitride layer made of titanium nitride on the surface. The electrolytic polishing allowance at this time is about 0.1 μm to 0.3 μm
Met. The surface of the wristwatch case after electrolytic polishing had a semi-pear finish with a slight loss of gloss. Next, the nitriding and surface-treated watch case was subjected to finish polishing on the entire surface with a centrifugal barrel polishing machine. The conditions at that time were as follows: walnut skin tape of about 3-5 mm was used as the medium, and 1500-2000 # Al20 was used as the polishing agent.
3 was added in an appropriate amount and polishing was performed for 15 hours. The polished watch case was completed by removing the polishing agent adhering to the surface. The surface of the watch case was uniformly polished, had a smooth semi-specular gloss, and exhibited a new texture that could not be obtained by conventional polishing methods alone, further enhancing the decorative value of titanium.

After that, the polished wristwatch case was subjected to a durability clutch test by measuring the surface hardness and the thickness of the nitride film layer in the cross section. Endurance clutch test is a tip knife edge
Prepare steel (Hv600) and apply 100g load to about 1
After moving 0 mm, the presence or absence of indentation scratches at that time was qualitatively confirmed. The results are shown in Table 1 in comparison with the conventional example.

[0009]

After the titanium decorative article is finished according to the present invention, the surface of the decorative article can be anodized so that it can be colored and the fashionability can be further improved.

[0011]

As described above, according to the present invention, a mirror-finished watch case is subjected to a nitriding treatment, the pole surface layer is electrochemically removed, and barrel polishing is performed.
A semi-specular gloss with an unprecedented finishing texture was obtained, which was even more advantageous in expressing the design. Further, since the surface layer is extremely hard, it is possible to prevent the occurrence of Dakon scratches and the like due to long-term use.

[0012] As a result, the functional and design expression of the titanium and titanium alloy ornaments is enhanced, which is industrially advantageous.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location G04B 37/22 N 9205-2F // C25F 5/00 8414-4K

Claims (1)

[Claims] 1. A step of shaping a decorative article such as a watch case, a band, a necklace, and glasses with titanium or a titanium alloy, a step of polishing the surface of the decorative article to a mirror finish, and a decorative article having the mirror finish. A step of nitriding, a step of electrochemically removing the nitrided gold-colored layer of the nitrided decorative article, and a step of barrel-polishing the surface of the removed decorative article to a semi-mirror finish. Finishing method for titanium ornaments characterized by.