US1904176A - Cadmium-nickel alloy - Google Patents

Description

Patented Apr. 18, 1933 UNITED STATES PATENT OFFICE CARL Es SWARTZ, OF PARK, ALBERT J. PHILLIPS, OF METU'GHEN, NEW JERSEY, ASSIGNORS TO AMERICAN SMELTINO- AND REFINING- COMPANY, OF NEW YORK, N. Y., A CORPORATION O]! NEW JERSEY CADMIUM-NICKEL ALLOY No Drawing.

This invention relatesto metal alloys and more particularly to alloys of cadmium and nickel which may contain small amounts of another metal or other metals, such as alumi:

num, antimony, popper, magnesium, zinc or the like. 4

The invention relates particularly to an alloy which may successfully be utilized as bearing metal at relatively high temperatures, that is, ,temperatures considerably in excess of those permissible when the conventional tin babbitts are employed.

Invgeneral, bearing metal alloys are composed of two distinct phases of widely vary ing physical properties. One of these phases is relatively soft, ductile, malleable; deforms with comparative ease, and is capable of creeping. The other phase is harder than the soft phase, but at the same time, 'is softer than the softest constituent of the shaft or similar structure which is supported or surrounded by the bearing metal. In use, the soft phase accommodates the individual characteristic of the shaft and, as this phase wears away, the hard phase becomes exposed, and, in addition to carrying the load, may make the actual metal to metal contact between shaft and the bearing in the momentary absence of lubricant.

In addition, it is fundamental that the,

range of operating or working temperature of any bearing is limited by the melting point of the bearing alloy or'the melting point of the lowest melting constituent present in appreciable amounts in the alloy. Be-

cause of this fact further advance in manymetals is admirably suited for use as bearing metal or the like.

In compounding the alloy, cadmium may Application filed December 13, 1982. Serial 1V0. 646,976.

be introduced into a suitable kettle and heated to a temperature of 400 to 450 C. under a suitable flux, which prevents oxidation and the production of undesirable dross and compounds during the formation of the alloy. For this purpose we find a low melting chloride slag, such as zinc chloride, gives excellent results. Pure, thin, sheet nickel may then be introduced and the molten bath agitated until the nickel is incorporated therein. Small quantities of other metals, such as aluminum,- antimony, copper, magnesium, zinc or the like, may then be added in amounts varying from traces up ,to 2 or 3%, depending on the particular metal added and the effect desired by its presence, such as the lessening of oxidation during casting, resistance to corrosion, increased strength and the like. When the nickel or nickel and accompanying constituents, if any, are thoroughly incorporated in and alloyed with the molten cadmium, the alloy may be cast i n'suitable molds to be used as desired.

When employed as hearing metal the alloy exhibits many desirable features and'characteristics. In the first place, the alloy may be successfully used at temperatures approaching 318 C. This is very important when it is remembered that ordinary tin babbitt has a maximum working temperature of approximately 200 C. due to the low melting point of its soft constituent.

As compared to tin babbitt, the cadmiumnickel alloy possesses approximately 50% greater tensile strength. Elongation of the alloy exceeds babbitt by approximately 35%; the yield'point in compression is nearly 40% greater; reduction of area in tension is approximately double and compression strength is about one-fourth greater. Again, the

Rockwell test shows greater hardness values for the new alloy.

While the creep value of the cadmium-nickel alloy is higher than the creep value of babbitts, it is appreciably lower than the creep values of bearing bronzes. In other words, the alloy of our invention will creep under a lower load than will the bronzes. This is of especial importance during the period when a bearing is running in and setting a shaft.

The coeflicient of friction of an alloy of 1 to 1.5% nickel and the balance cadmium is about equal to that of babbitt.

As previously mentioned, the properties of the cadmium-nickel alloy may be modified by the addition of small amounts of other metals. For example, by adding, say, 0.5% copper to a cadmium alloy containing 1.5% nickel, the tensile-strength is nearly double that of tin babbitt, while, at the same time, elongation and reduction of area in tension compares favorably with babbitts. Again, small quantities of magnesium aid in retarding oxidation of the alloys. Similar beneficial results are obtained with small additions of aluminum, antimony and/or zinc.

Although the nickel content may vary from 0.25% to 7% as specified, we find that, for most purposes, a range in the nickel content of from 0.6% to 4% gives the better results. In other words, a minimum of 0.25% nickel is necessary, while, if more than 7% nickel is used, the characteristics which make the alloy desirable for use as bearing metal are modified or disappear.

The present application is a continuationin-part of our copending application, Serial No. 620,305, filed June 30, 1932.

While certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be effected by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. A metal alloy containing from 0.25%

to 7% nickel, magnesium and zinc in appreciable quantities not exceeding a total of 3% and the balance cadmium. 2. A bearing metal alloy comprising 0.25% to 7% nickel, magnesium and zinc in appreciable quantities not exceeding a total of 3% and the balance cadmium.

3. A metal alloy comprising 0.25% to 7% nickel, magnesium a total of 3% and the balance cadmium.

4. A bearing metal alloy comprising 0.25% to 7% nickel, magnesium in amounts not exceeding a total of 3% and the balance cadmium.

5. A metal alloy comprising 0.25% to 7% nickel, zinc in amounts not exceeding a total of 3% and the balance cadmium.

6. A bearing metal alloy comprising 0.25% to 7% nickel, zinc in amounts not exceeding a total of 3% and the balance cadmium.

In testimony whereof we have hereunto set our hands.

CARL E. SWARTZ. ALBERT J. PHILLIPS.

in amounts not exceeding