US1815071A - Nonferrous alloy - Google Patents

Description

Patented July 21, 1931 I I UNITED STATES PATENT OFFICE WILLIAM 13. PRICE, or WATERBURY, CONNECTICUT, ASSIGNOR TO SCOVIL L MANU WATERBURY, CONNECTICUT, A CORPORATION or C01\T FACTURING COMPANY, OF NECTICUT No Drawing. Application filed April 16,

This invention relates to an improvement in non-ferrous alloys and particularly to an 1 alloy whose principal constituent is copper,

denser tubes are subjected in use. One of the important properties of the present alloy is that it can be extruded into tube or rod form at a lower temperature and with less pressure than alloys heretofore particularly suitable for condenser tubes.

The preferred composition of the new aloy is: Per cent Copper 80 Aluminum 2 NickeL The remainder of the alloy is substantially all zinc, and in no case must there be any appreciable amount of tin present.

In commercial practice an alloy made from commercial material proportioned to give the composition above stated, when analyzed showed the following composition:

' Per cent Copper 80. 16

Aluminum 2'. 07

The percentage of zinc .Was determined by Nickel Zinc 40 difference and of course might include traces of impurities, for example, lead, iron or other ingredients, which, however, if present, were in too small an amount to aflect the properties of the alloy.

This commercial alloy when cast in a slab of about inch thickness had a hardness of 45 Brinell.

The cast slab was rolled to a thickness of 0,151 inches and then annealed for one hour at 750 C. to relieve it of internal stresses,

NONFERROUS ALLOY 1931. Serial No. 530,735.

Its hardness then was 53 Brinell. It was then rolled to .050 inch finish gage.

The physical properties of the alloy in its ililferent conditions were found to be as folows:

Soft an- Light nealed annealed Hard Yield point 17, 0B0 57, 000 116. 000 Tensile strength 58, 000 78, 119, 000 Elongation 58% 33% 4% The alloy was tested for tensile strength,

elongation (in 2 inches) and reduction of area, with the following results:

Tensile Rerluc Elonga strength tion in Temperature lbs. per 22 2 area, per

sq. in. cent The alloy of the present invention has a high resistance to corrosion and oxidation, and retains a relatively high resistance to oxidation at elevated temperatures, there being substantially no change in color orevidencecof oxidation at temperatures up to 600 It was found that the freedom of the alloy s from tin was particularly important in the manufacture of condenser tubes from ingots of the alloy by extrusion methods. When tin was present, even in small amounts, the ingot could not be extruded in a special tube extrusion machine of 900 tons capacity, unless the ingots were heated to a high temperature, for example, above about 950 C., at which the tin liquidated. By omitting the tin the alloy could be readily extruded at the customary temperatures and pressures of working.

Also by omitting the tin the resistance to corrosion and oxidation at elevated temperatures was greater than when tin was present. Extruded condenser tubes made from the alloy of the present invention gave, when the remainder being inostly zinc.

tested, at normal temperatures, the following results:

, Tensile Yield Elongastrength pointlbs. tion per lbs. per per sq. cent in sq. in. in. 2"

Hard 119,900 110,000 4 Relief annealed 78,000 37,000 33 Annealed at 050 0 7 58,000 11,000 '58 What is claimed is:

1. An alloy compnsmg essentlalamounts of copper, alummum and mckel 1n proportlons substantlally' -w1th1n the followmgranges:

t Per cent Copper 80 to 85 Alummum u 1to 2 Nloke 1 to 2% 2. An alloy consisting of the following ingredients in proportions substantially as stated:

Per cent Copper 80 Aluminum," 2 Niolzel Zinc 17 In testimony whereof, I have hereunto set my hand.

WILLIAM B. PRICE.