JPS63317241A - Production of titanium-copper strip - Google Patents

Abstract

PURPOSE:To improve the quality and characteristic of a titanium-copper strip by rapidly solidifying molten metal composing of the specific wt.% of Ti and the balance Cu with impurities at the specific range of cooling velocity and next continuously cooling to the room temp. CONSTITUTION:A trough 10 is arranged below a tundish 9 and at the downstream side, the water cooling rolls 11, trough 13 and winding machine 14 are in order arranged. The molten metal composing of 1-7% Ti and the balance Cu with inevitable impurities is poured into the tundish 9 from a ladle 8. Next, it is supplied to gap between the cooling rolls 11 from the tundish 9 through the trough 10 and rapidly cooled at >=10<2> deg.C/sec and <10<5> deg.C/sec the cooling velocity and solidified and naturally cooled. By this method, crystal grain size becomes <=50mum and development of non-solid solution of Ti is restrained. Therefore, rolling workability of the titanium-copper strip is improved and the quality and the characteristic are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a titanium-copper thin plate by a rapid solidification method.

[Conventional technology]

BACKGROUND ART In the past, casting using a vertical continuous casting device and batch casting using a metal mold were generally used as methods for manufacturing titanium copper ingots. Fig. 2 is a sectional view showing a conventional vertical continuous casting apparatus. In Fig. 0, (1) is a melting furnace;
2) is a molten metal, and (3) is a holding furnace that keeps a certain amount of this molten metal in a constant state. (4) is a graphite mold fixed in this holding furnace.

(5) is a water cooling jacket provided so as to surround this graphite mold, and (6) is an index roll for drawing out the ingot (7) which has been solidified by cooling the molten metal (2).

The conventional method for manufacturing titanium-copper thin sheets is to use the above-mentioned casting equipment by pouring the molten metal (2) stored in the holding furnace (3) into the graphite mold (4) and flowing it through a water channel inside the water-cooling jacket (5). The ingot (7) is cooled and solidified by cooling water and sent out from the mold (4) as an ingot (7). At this time, the ingot (7) is continuously or intermittently pulled out by index rolls (6) to continuously form a long ingot. (7) is cast. After that, forging, rolling, and heat treatment are repeated to finish the thin plate to the desired dimensions.

[Problem that the invention seeks to solve]

However, in the conventional manufacturing method of titanium-copper thin sheets as described above, the cooling rate is slow, so the crystals become enlarged during the production of the ingot, and since there is undissolved Ti, it is difficult to improve the processability later. It is necessary to perform a homogenization treatment at high temperature for a long time, and it has been impossible to eliminate undissolved Ti.

This invention was made to solve the above-mentioned problems, and it produces an ingot with small crystal grains and low amount of undissolved Ti, and eliminates the need for long-term homogenization heat treatment at high temperature. An object of the present invention is to provide a method for manufacturing a titanium-copper thin sheet that can produce a thin sheet that has good rolling workability and has better spring characteristics than thin sheets obtained by conventional manufacturing methods.

[Means for solving problems]

In the method for producing a titanium-copper thin plate according to the present invention, Ti is 1 to 1.
A molten metal consisting of 7% copper, the balance being Cu and unavoidable impurities, is rapidly cooled and solidified at a cooling rate of 10"C/sec to 10"C/see, and then continuously cooled to room temperature. This is the way to do it.

[For production]

In the method for producing a titanium-copper thin plate according to the present invention, the molten metal having the above composition is
By rapidly cooling at a cooling rate within a range of less than ee, an ingot with a grain size of 50 μm or less and a small amount of undissolved Ti can be obtained, improving rolling workability and improving the properties of the final product.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view of a twin-roll metal quenching casting apparatus used in an embodiment of the present invention.

In the figure, (8) is the molten metal (
(2) is a ladle for pouring the molten metal (2), (9) is a tundish for storing the molten metal (2), and (10) is a gutter that guides the molten metal (2) flowing out from the tundish to a designated place. 2) Heat retention means are provided to prevent solidification. (11) are water-cooled cooling rolls arranged vertically with variable gaps, and the roll rotation speed can also be adjusted arbitrarily.

(12) is a thin plate ingot formed by passing the molten metal (2) through the cooling roll (11). (13)
A guide is used to guide the thin plate ingot (12) to a winder (14) for winding it up.

A method for manufacturing a titanium-copper thin plate is that in the metal quenching and casting apparatus described above, molten metal (2) is passed from a ladle (8) to a tundish (9).
) and stored, and then supplied from the tundish (9) through the gutter (10) to the gap between the cooling rolls (11), and between the cooling rolls (11) at a rate of io"°C/sec or more of 10
The ingot (12) is instantly cooled and solidified in a range of less than "C/see" to form a thin plate ingot (12). Take machine (
14) and wind it up continuously.

By rapidly solidifying the titanium-copper alloy in this way, a thin plate ingot with a grain size of 50 μl or less, undissolved Ti kept small, and the appearance of the β phase, which has poor workability, suppressed can be obtained. Diffusion proceeds rapidly during heat treatment, and the presence of undissolved Ti can be eliminated. Therefore, workability in post-processing is improved, and with the same Ti content, a product with improved tensile strength and spring limit value can be obtained compared to the conventional method.

In the above manufacturing method, as the cooling roll (11),
Molten metal (2) is poured into the cooling roll (11) at a rotation speed of 15 rpm using a water-cooled cast iron roll with a diameter of 200 mm and internal cooling water at a temperature of 1100°C.
As a result, the ingot dimensions were 1.8 mm thick x 130 m wide.
A thin plate ingot (12) of intestine titanium copper could be obtained.

By the above method, a molten metal containing 1.9% by weight of Ti and a balance of Cu, a molten metal of 4.0% by weight of Ti and a balance of Cu, and a molten metal of T
i 6.1% by weight, the balance is Cu.
．． The plate was rolled to 3 mm, subjected to continuous quenching at 850°C, and finished to a thickness of 0.2 mm with a cold working rate of 37%. It was used as a sample.

Table 1 summarizes the characteristic values of the present invention material and comparative material. The comparative material was cast using a conventional vertical continuous casting machine, subjected to homogenization treatment at 850℃ for 4 hours, then subjected to hot forging heat treatment and rolling processing. After being quenched and finished at a cold working rate of 37%, the material was heat treated at 400° C. for 1 hour.

From the above results in Table 1, it can be seen that the material of the present invention has higher tensile strength and spring limit value than the comparative material.

As described above, according to the present invention, by rapidly cooling and solidifying molten titanium steel, it is possible to obtain an ingot with a crystal grain size of 50 μm or less and less undissolved Ti, which has good workability. Thus, a titanium-copper thin plate with excellent spring properties can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a twin-roll type metal quenching spinning apparatus used in an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional vertical continuous casting apparatus. In the figure, (2) is the molten metal, (8) is the ladle, (9) is the tundish, (10) is the gutter, (11) is the cooling roll,
(12) is a thin plate ingot, and (14) is a winder.

Claims (2)

[Claims] (1) Molten metal consisting of 1 to 7% by weight of Ti, the balance being Cu and unavoidable impurities, at 10^2°C/sec or more for 10
A method for producing a titanium-copper thin plate, which comprises rapidly cooling and solidifying the titanium-copper thin plate at a cooling rate of less than 5° C./sec, followed by continuous cooling to room temperature. (2) The method for producing a titanium-copper thin plate according to claim 1, wherein the rapid cooling is performed using a water-cooled cooling roll.