US2136212A - Copper alloys - Google Patents

Description

Patented Nov. 8, 1938 UNITED STATES PATENT OFFICE corrnn armors Franz R. Hensel and Earl I. Larsen, Indianapolis,

Ind., assignors to P. R. Mallory & C0,, 1110., Indianapolis, Ind., a corporation of Delaware No Drawing.

Application September 10, 1938,

Serial No. 229,331

3 Claims.

connection with the appended claims.

The present invention comprises the combination of elements, methods of manufacture and the product thereof, brought out and exemplified in' the disclosure hereinafter set forth, the scope of the invention being indicated in the appended claims.

The. present invention contemplates an alloyof the following elements in substantially the following proportions:

Per cent Nickel .1- Beryllium ,65- 3 Silicon ,65- 5 Copper Balance.

The preferred alloys contain nickel and silicon in substantially the weight ratio of 4:1 so as to produce nickel silicide corresponding approximately to the formula NizSi. The preferred proportions of ingredients are Per cent Nickel silicide i to 5 'Berylli .05 to 3 Copper Balance.

very materially and at the same time produces a material of superior fatigue and impact properties and better ductility. a

The alloys can be made according to standard alloying methods. After the alloy has been melt ed and cast, the material may be heat treated in the form of a casting or wrought material by first quenching the alloy from a temperature exceeding 700 degrees C., and subsequently aging at a temperature below 700 degrees C. If the materials are worked, it is desirable to quench the materials from intermediate anneals, cold working same and applying an aging treatment afterwards. This cold working before aging hastensconsiderably the precipitation, of the dispersed phase. An experimental alloy was made-up of the following composition:

Percent Nickel 2.3 Silicon .7 Beryllium .5 Copper Balance.

This alloy gave the following results:

a. Quenched from 950 degrees C. and aged 16 hours and 400 degrees C.--102 Rockwell 13 hardness.

b. Quenched. from 950 degrees C. and aged 16 hours and 450 degrees C.--98 Rockwell B hardness. I

c. Quenched from 950 degrees C. and aged 16 hours and 500 degrees C.--94 Rockwell B.

d. Quenched from 750 degrees C. and aged 16 hours and 400 degrees C.7 5 Rockwell B.

e. Quenched from 850 degrees C. and aged 16 hours and 400 degrees C.93 Rockwell B.

I. Quenched from 900 degrees C., aged 16 hours and 400 degrees C.9'7 Rockwell B.

The above data show that a very high Rockwell B hardness can be obtained exceeding 100 with the correct heat treatment. The above mentioned tests were made on castings. By using an alloy containing only nickel and silicon in the approximate proportions of 4:1,. the maximum hardness obtained is considerably lower and is in the neighborhood of 88-90 Rockwell B.

The addition of beryllium to nickel silicide alloys lowers the aging temperature at which the maximum hardness can be obtained; however,

the hardness will not drop very much, even though considerably higher aging temperatures are used. This makesthis new type of alloy highly useful for a large number of applications, because the temperature spread at which aging can be obtained is rather wide. Our experiments showed that alloys without the addition of beryllium will not age at all, or only very slightly, if heated to 400 degrees C., while straight copper-beryllium alloys will soften when heated to such high temperatures as 500 degrees C.

The plain nickel silicide alloys have also shown considerable disadvantages in the as cast conditions; namely, internal shrinkage, low tensile properties and very low ductility. The addition of beryllium to these alloys has resulted in a 7 much finer grained and denser casting, with improved physical properties.

Another type of alloy mum; in the same class which was studied, contained Per cen Nick .8 Silicon .3 Beryllium 2.0 opp Balance In this alloy, the beryllium contained is pre dominant, and the nickel silicide content was lowered to about 1%. The result oi. this change is a further increase in hardness, but a. decrease general machinery or electrical machinery, and

on account or its strength at elevated temperatures, it is suitable for parts in internal comhustion engines.

While the present invention as to its objects and advantages has been described herein as carried out in specific embodiments, it is not desired to be limited thereby, but it is intended to cover the invention broadly, within the appended claims.

What is claimed is:

1. An age-hardened alloy composed of .05 to 3% beryllium, .1 to 10% nickel,.05 to 5% silicon and the balance substantially all copper, characterized by high hardness. 800d resistance to fatigue and to impact, ductility, and a dense fine grained structure.

2. An alloy composed of .05 to 3% beryllium, .1 to 10% nickel, .05 to 5% silicon and the balance copper.

3..An alloy composed of .05 to 3% beryllium, .1 to5% nickel silicide and the balance copper.

FRANZ R. HENSEL. EARL I. LARSEN.