Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS2169441 A
Publication typeGrant
Publication dateAug 15, 1939
Filing dateSep 23, 1937
Priority dateJun 2, 1937
Publication numberUS 2169441 A, US 2169441A, US-A-2169441, US2169441 A, US2169441A
InventorsWinter Herbert, Fahrenhorst Wolfgang, Schmid Erich
Original AssigneeNew Jersey Zinc Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Working zinc alloys
US 2169441 A
Abstract  available in
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

, Patented Aug. 15, 1939 UNITED STATES PATENT OFFICE WORKING ZINC ALLOYS Application September 23, 1937, Serial No. 165,322 In Germany June 2, 1937 4 Claims.

This invention relates to improvements in forming alloy metal objects and particularly to working zinc alloys containing from 10 to 20% aluminum to produce'an alloy object without im- 6 pairing the mechanical properties of the alloys.

Zinc generally is rolled at temperatures below 200 C. because its rollability is decreased at higher temperatures. The presence of other substances in the zinc generally decreases the rollability so that the rolling temperature must be increased in the case of zinc alloys. However, in practice, temperatures of 270 C. are not exceeded because this tends to bring about deterioration in the mechanical properties of the rolled alloys. Moreover, the temperature cannot be decreased below 180 C. on account of the high roll pressures then requisite. (A. Burkhardt, Technologie der Zinklegierungen, Berlin 1937, page 192.)

We have found, however, that aluminum-bearing zinc base alloys containing from 10 to 20% of aluminum can readily be rolled and otherwise worked at temperatures between 270 and 380 C.. and preferably at a temperature of about 340 C. Although the addition of aluminum generally decreases the rollability of zinc so far that at 25 medium temperatures only slight decreases in thickness are possible at each pass, it was unexpeetedly found that at temperatures about 270 C. the malleability of zinc-base alloys containing 10 to 20% of aluminum increased so suddenly and the work of deformation decreased so rapidly that in this range hot working is possible with heavy reductions at each pass. The mechanical properties of the resuting zinc alloy objects are not impaired by this method of treatment, but 3 instead are generally improved. Thus we have discovered that the malleability of an alloy consisting of 10 to 15% aluminum, 1.5 to 4% copper and .01 to .04% magnesium, the balance of the alloy being zinc having a purity of at least 99.98% (as described in co-pending United States application No. 159,711, filed August 18th, 1937, by Herbert Winter, and subsequently issued as United States Patent No. 2,102,869, on December 21, 1937) increases suddenly at temperatures above 270 C. and retains this increased mallea- -bility to. a temperature of about 380 C. At a temperature of 340 C. the malleability of this alloy is optimum.

Our invention, therefore, contemplates the improvement in the manufacture of zinc base objects which comprises working at a temperature ranging from 270 C. to 380 C., and preferably at 340 C. a zinc-base alloy containing from 10 55 to 20% aluminum, and more particularly an alloy consisting of 10 to 15% aluminum, 1.5 to 4% copper, .01 to .04 magnesium, the balance of the alloy being zinc having a purity of at least 99.98%. When such alloys are thus worked, there is no deterioration in their mechanical properties. On the contrary, the resulting metal objects possess high tensile and impact strengths, 6 improved machinability and high resistance to corrosion.

The curves A and B in the accompanying single figure illustrate the sudden increase in malleability of aluminum-bearing zinc base alloys that we have discovered. Two alloys A and B were subjected under constant load to difierent temperatures. In the figure the ordinates show the change of form suffered by the test rods under a compression of 7.5 kilograms per square millimeter. The change in form was measured in per cent decrease in the height of the pieces under compression. The abscissae in the figure show the temperature of deformation in degrees Centigrade. The compositions of the alloys investigated were as follows:

We claim:

1. In the manufacture of zinc alloy objects, the improvement which comprises working at a temperature ranging from 270 to 380 C. an aluminum-bearing zinc base alloy containing from 10 to 20% aluminum.

2. In the manufacture of zinc alloy objects, the improvement which comprises working at a temperature of about 340 C. an aluminum-bear ing zinc base alloy containing from 10' to 20% aluminum.

3. In the manufacture of zinc alloy objects, the.improvement which comprises working .at a temperature ranging from 270 to 380 C. an alloyconsisting of 10 to 15% aluminum, 1.5 to 4% copper and 0.01 to 0.04% magnesium, the balance of the alloy being zinc having-a purity of at least 99.98%.

4. In the manufacture of a zinc alloy object, the improvement which comprises working at a temperature of about 340 C. an alloy consisting of 10 to 15% aluminumflfi to 4% copper, and 0.01 to 0.04 magnesium, the balance of the alloy being zinc having a purity of at least 99.98%.

HERBERT WINTER. WOLFGANG FAHRENHORBT.

ERICH SCHIJID.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2516737 *Jan 15, 1944Jul 25, 1950New Jersey Zinc CoHot-rolled binary zinc-titanium alloy
US3753791 *Jan 4, 1971Aug 21, 1973Imp Smelting Corp LtdHeat-treatment of zinc/aluminium alloys
US3966505 *Apr 30, 1975Jun 29, 1976Ball CorporationHigh strength wrought zinc alloy
US3972743 *Oct 20, 1975Aug 3, 1976Ball CorporationHigh strength, stable zinc-aluminum alloy
US4599279 *Oct 1, 1984Jul 8, 1986Ball CorporationZinc alloy for reducing copper-zinc diffusion
US6383657Dec 18, 2000May 7, 2002Alltrista Zinc ProductsAluminum clad zinc bimetallic coin planchet
Classifications
U.S. Classification72/364, 148/441, 72/700
International ClassificationC22F1/16, C22C18/04
Cooperative ClassificationC22C18/04, C22F1/165, Y10S72/70
European ClassificationC22F1/16B, C22C18/04