US1496269A - Alloy - Google Patents

Description

Patented June 3, 1924.

,TED STATES I'IYRO IYTAKA, or TOKYO, JAPAN, ASSIGNOZR. 'ro MITSUBISHI ZOSEN KAISHA, M11, or TOKYO, JAPAN.

...- ALLOY.

No Drawing.

To all who-21bit may concern Be it known that ITYRO IYTAKA, a subject of the Emperor of Japan, residing at No. 26 Sanchome Sugamomachi, Tokyo Prefecture, Japan, has invented certain new and useful Improvements in Alloys, of which the following is a specification.

This invention relates to a special alloy which contains copper as its largest constituent and together with nickel, and a small amount of aluminum.

The object of the invention is to obtain materials practically unoxidizable even at high temperatures, and at the same time of great strength and fair ductility, so that it can be profitably used for engineering purposes where unusual strength and resistance to heat are desirable.

The alloy has a great power of resisting corrosion by atmospheric influences and by sea Water, and isquite superior in that respect to other similar alloys.

The objects of the invention are accomplished in an alloy of copper with nickel which also contains 11 per cent or less of aluminum. The alloy so made possesses unoxidizability both at ordinary and high temperatures. An alloy of nickel and copper without aluminum is well known. I shall now describe the manufacture and characteristics of the special alloy embodied in my invention, giving a few examples.

Example 1.Alloy of copper and nickel with aluminum. This is formed by alloying aluminum with copper and nickel alloy. The usual alloy of copper and nickel in varyingproportions is always in a single phase solid solution and can be easily worked, and consequently it is very extensively employed for various purposes. The alloy containing from 3 per cent to 25 per cent of nickel is used for locomotive fire-box plates and boiler tubes the one containing 40 per cent of nickel fb and electric resistance wires; and that of from per cent to 70 per cent of nickel content is known under the name of Monel Application filed January 7, 1921.

r thermo unction Serial No. 435,688.

metal and is said to have resisting power against corrosion by atmospheric and sea water, and also to possess great strength so and elongation and is widely used for varied purposes.

After thorough investigations it was found, however, that all of the copper-nickel alloys were liable to be oxidized consider- 55 ably at comparatively low temperatures from 400 to 500 C. The oxidation is so' great that they are not proper materials to be used as engineering materials to with stand intense heat, e. g., boiler tubes.

The special alloy of my invention formed of these known alloys with an addition of suitable amount of aluminum, is much more resistant to oxidation. According to practical tests, the materials have been kept in oxygen gas at 800 C., for more than ten hours, without having been affected at all; even the lustre not being lost. It is needless to mention that other alloys, subjected to a similar test, oxidize until the material ultimately becomes a rust. This proves the superiority of this alloy to be really remarkable.

With regards to strength, elongation and other properties, the new alloys surpass by far, those of the aluminum bronze (alloy of Cu and Al only) and other similar alloys.

The superior mechanical properties of this special alloy can be developed by special treatment; this alloy, after being cast and annealed, can withstand high stresses, up to 35 tons per square inch, with 15 per cent elongation.

With an adequate proportion of nickel and aluminum, this alloy may have atensile strength of 30 tons per square inch with an elongation of 30 per cent in annealed state. If further mechanical treatment is given, the strength and ductility can be increased even more, and with special proportions of the three elements contained, the alloy as cast may have a strength of over 50 tons per square inch.

It may be rolled and hammered, and therefore it can be readily and successfully I claim:

Worked. An alloy consisting essentially of 7 4 to One example of the percentage of the con- 97% of copper, 2 to 11% of aluminum, 1 to stituents of this alloy may be approximately 15% of nickel. 15 5 as follows:- In testimony whereof he afiixes his signagoplpeir jfrom 37 per cent to 74 per cent. ture.

ic e rom .per cent to 15 per cent. Aluminum from 2 per cent to 11 per cent. ITYRO IYTAKA' The presence of minor amounts of impuri- Witnesses: 10 ties in the constituents does not interfere GENJI KURIBARA,

' with the useful properties above mentioned. C. ARcILLAe.