US1546657A - Aluminum alloy - Google Patents

Description

Patented July 21 I925.

'rnxarnsu manna, or xYo'ro, JAPAN.

nnumum Anno llo Drawing.

7'0 all whom zt may concern:

Be it known that I, TAKAYASU HARADA, a subject of the Empire of Japan, residing at care of Institute of illletallurgy, College of Engineering, Kyoto Imperial University,

Kyoto, Japan, have invented certain new and useful Improvements in Aluminum Alloys, of which the following is a specifica-. tion.

This invention relates to an alloy containing Ou:0.3-6%, Ni: 0.545%, Mn: 05- 0% the remainder being aluminum. The particular object of this invention is to produce an aluminum alloy resistant to weak acids, ll!v solutions of salts and weak alkalis, having great hardness, strength and ductility.

The composition of this alloy is 00:03- 6%, Ni: 0.543%, Mn 0.56%, the balance being aluminum. v 1

The method of manufacture is as follows :Prepare beforehand three hard! eners, i. e. the first hardener is an alloy of A1:Cu:: 75 :25, the second hardener is an alloy of A1:Ni:: 75 and the'third hardener is an alloy of Alzlllnn :25..

An amount of aluminum metal is first melted in a graphite crucible in a coke'furnace atabout 800 C. amounts of the three add the calculated hardeners in it, and

agitate well with an iron rod. If they mixed as in the case 0 homogeneously, take the crucible out of the furnace, put a little zinc-chloride on the surface of the molten alloy and take off the reater part of the slag, cool to about 700 and cast in-iron chill-moulds, to form slabs. j i

Rolling and pressing may be carried out aluminum metal. At present it is diflicult to separate small rcentages of iron from aluminum. Its influence on aluminum are (1) it makes aluminum very corrosive, (2) it stains the surface of aluminum with black or dirty compounds when brg ht in contact wit even weak organic ac or. some salts, (3) it s ils the mechanical properties of aluminum. 0.345% of copper in this alloy relieves all these ill-effects of iron perfectly, H

promotes mechanical properties and and resistivit t0 corrosion. 4

The a by of aluminum and manganese is very resistant to corrosion and has a minute grain point of this alloy, the grains of the alloy are evidently minute and do not grow larger even after long use. I

structure. Near the eutectic- Applicatlon fllcd June 4, 1924. Serial No. 717,845.

Nickel in this alloy also has the same efiect as'manganese and copper and makes a more resistant alloy having a more minute grain structure than that containing no 60 nickel.

As above mentioned, this alloyis almost absolutely non-corrosive when in contact with organic acids, .solution of salts and alkalis (except caustic alkalis), and also inorganic acids. V

The examples of resistance. to corrosion are shown in Table 1 and its mechanical properties are shown in Table '2. TABLE 1.'0orr0sion tests income-examples.

(B) G Cu.... 1. 0 6a.... 1. n 'Cu... 11-... 11-... -Ana3ysls Fen" Fan 0, 0,

.06 Si"-.. 0 06 0 S1....

Al: balance. 1 111:

For 30 days, at room temperature, dipped in these reagent: 7

a 057 NH 0H {%o110ss inwt 0.0000 0.0014 0. 1 Gr. otlosspersq. cm..-- 0.00000 0.00001 0.00001 37 N80] '{%ollossinwt 0. 0.0000 0.1!!!) Gr. otloss persq. cm.... 0.00000 0.00000 0.00000 a7 Nmcm %oflosslnwt 0.0060 0.0065 0.1034

Gr. oflosspersq.c1n 0.00003 0.00004 0.00002 3% citric and %oflossinwt 0.0000 0.0029 0.0032

malic acids.-- Gr. efloss per sq. cm 0.00000 0.0003 0.00002 Na Sm %oflossmwt 0.0000 0.0000 0.11113 0 Gr. ofloss persq. can... 0.00000 0.00000 0.00001 Japanese %of1ossinwt 0.0000 0.0000 0.0000

oyu Gr. 011m per sq; cm.... 0.00000 0.00000 0.00000 Japanese %o[loss1nwt 0.0000 0.0000 0.01110 scr e ass 0 use n 5 mm 3:. of loss pg't sq. 0mm. g oom agi x aa gg i 05$ dnouoss per sq. 0111---- 0.00010 000000 0.00004 %0[l0SSiDWl I .3052 1.3103 1.0030 Gr.o1'1osspersq. 01m... 0.00095 0.00554 0.00136 .0'57' H o 011085 in .2845 1.3745' 1.0014

0 1-. otloss-per sq. 05.--- 0.00758 000500 0.00040 057 BN0 7 ollossmwt 1.1064 1.1066 1.0851.

- v dr. ol'losspersq. 0111---- 0.00678 000078 00113 0. N. B. Shoyu is a kind or sauce made from common salt and TABLE 2. -MechanicaZ tests of an example.

Analysis .-Cu:1.48'7$ N1: 2.00%, Mn:2.37%, Fe: 0.47%.

- S1: 0.0! A]: Balance. cold worked.....2)34 k mm or 12.8-21.7 Tensile strength in (thin plate) annealed .-l8. g- 2f k z l mm or 11.0-14.7 Elo etlon 7J2 cold worked a 1n (thlnfilste annealed. 10-13 a ardness rin c No. with 500k; dworked 05-70 p e lhlck- Depthness. olcup.

I 0.3mm 2.86m!!! coldworxed 0.4mm 3.25m Clgfih i testswith' 0.6mm 3.65mm c ontest.-... 0.3mm Lemma 4 annealed 0.4mm 068mm 0. 5mm 6.81m

In conclusion, the special properties of corrosive when in contact with organic ac1ds,'weak'alkal1s and solutlon 'of many of the alloy are very minute; (3) its mechanlcal propertles are very superior; (4:) impure aluminum lng'ots can be used to I make this alloy.

As a result, this alloy is inost suitable to make utensils which are used in contact with 7 weak acids, alkalis" on solutions of salts,

especially for kitchenwares.

I claim An aluminum alloy containing 0.3-6% of copper, 0.56% of nickel, 0.5-6% of manganese the 'balance being, aluminum and impurities.

In witness whereof I have signed this specification in presence of two witnesses.

Dated this 8th day of May, 1924.

TAKAYASU HARADA.

Witnesses:

- G. T. OGATA,

IOHIRO SUDZUKI.