US1874617A - Non-ferrous alloy - Google Patents

Description

Patented Aug; 30, 1932 UNITED STATES PATENT OFFICE WILLIAM B. PRICE, OF WATEBBURY, CONNECTICUT, ASSIGNOR '10 SCOVILL MANUFAC- TURING COMPANY, OF WATERBURY, CONN ECTIOUT, A CORPORATION CUT No Drawing.

This invention relates to a non-ferrous alloy, and particularly to an alloy comprising copper, aluminum, nickel, and tin as the essential ingredients.

Alloys have been made heretofore consisting essentially of copper, zinc and tin .and are in general use on account of their valuable properties.

Also alloys consisting essentially of brass with a limited amount of aluminum are in general use and are valuable for many purposes.

I have discovered that alloys consisting essentially of copper, aluminum, nickel and tin, the said ingredients being within the general ranges hereinafter specified, have new valuable characteristics not heretofore found in the non-ferrous alloys of copper heretofore employed.

An alloy made in accordance with the present invention is suitable for the same uses as the prior copper, zinc, tin alloys and has the great advantage over the said alloys that it is moreresistant to oxidation at high temperatures, is practically immune toseason cracking, and is more readily worked at hot and cold temperatures. v

A further advantage of an alloy embodying the present invention is that its tensile stren h is greater than that of the correspon' ing copper, zinc, tin alloy and that in its soft state it has a greatly increased percentage of elongation.

Another important advantage of an alloymade in accordance with the present invention is its remarkable physical properties at elevated temperatures. For example, at 500 C. it had a tensile strength of 28,900 pounds per square inch, whereas the prior alloys of copper, zinc, and tin at the same temperature had a tensile strength of only 6,900 pounds per square inch. At a temperature of 750 C. the alloy constituting the present invention had a tensile strength of 4,300 pounds per square inch, an elongation of in two inches and a reduction in area of 43%. The prior alloys of copper, zinc and tin, at the same temperature had a tensile strength of only 1,600 pounds per square inch, an elon- Applioation filed June 4, 1930. Serial No. 459,261.

gation of 23% in two inches and a reduction in area of 24%.

An alloy made in accordance with the present invention comprisesas essential ingredi- OF CONNEC'II- ents the following metals; in about the ranges stated;

Copper from to parts, aluminum from 1 to 2% parts, nickel from 1 to 2 parts, tin from 1 to 2 parts. Where the percentages of the above metals in any given alloy do not constitute one hundred percent, the difference most advantageously is zinc, but, of course, in practice other impurities may be present without injury to the resultant pro high as about 16 percent of zinc may be present and is advantageous for some purposes. Also, because it cannot be avoided without too much expense in refining the constituent metals, there may be and usually are some lead and iron present.

The following is an example of an alloy constituting the preferred embodiment of the invention for use as condenser tubes.

not. In practice it is found that as Per cent Copper 80 Aluminum 2 Nickel z 1 Tin 1 Zinc 16 ,In commercial practice an alloy made from commercial material proportioned to give the composition above stated, when analyzed gave the following composition:

This commercial alloy when cast in a slab about inch thick had a hardness of 65 on the Brinell scale. It was rolled as cast to 0.158 inch thick, then annealed for one hour at 750 C. to relieve it of internal stresses. Its hardness was still 65 Brinell. Then it was rolled to .050 inch finish gage. In this contion of 2 inch test dition its tensile strength was 112,000 pounds per square inch and the percentage of elongapieces was 3 Its hardness on the Vicker s machine was equivalent to 230 Brinell.

The great advantage of this material for condenser tubes is its resistance to corrosion in salt water, apparently due to the formation of a protectlve scale or surface film resistant to oxidation by air, resistance to air impingement attack, the absence of red stains after pickling, which is a general defect of prior copper alloys made for similar uses, and particularly the increased tensile strength.

What I claim is:

1. An alloy comprisin essential amounts of copper, aluminum nic e1 zinc, and tin in proportions substantially wlthin the followmg ranges Per cent Copper 80 to 85 Aluminum 1 to 2% Nickel 1 to 2 Tin 1 to 2% Zinc 7 to 17 2. alloy consisting of the following ingretiiants in proportions substantially as sta C Per cent 0 r 80 Alsl fnflm 2 Nickel 1 Tim. 1 Zinc 16 In testimony whereof, I have hereunto set my hand.

WILLIAM B. PRICE.