The Rate of Precipitation of Copper Aluminide in the Silver Rich Silver-Copper-Aluminum Alloys

In order to determine the best annealing temperature at which to age-harden the alloys, hardness tests on speci­men annealed for different lengths of time at different temperatures were made.

Age Hardening of Copper-Aluminum Alloy Castings

Age hardening occurs in alloys of the solid solution type containing a hardening constituent, be it metal or metallic compound, which is more soluble in the solvent phase at higher temperatures than at lower ones.

The Electrical Conductivity of the Copper-Aluminum Alloys.

Among the many aluminum alloys which have been studied are the binary copper-aluminum alloys. These have proven to be among the most useful of the alumi­num alloys thus far worked upon.

The Effect of Manganese and Magnesium on the Hardening of Copper-Aluminum Alloys

During recent years, duralumin and all aluminum alloys have been made the object of much discussion regarding their hardening mechanism. The commercial success of nearly all of the alloys of aluminum and mag­nesium is dependent on their ability to age or precipitation harden.

The Age Hardening of Silver with Copper-Silicide

The successful application of the phenomenon of pre­cipitation hardening to aluminum and copper has indicated the possibility of hardening all metals in the same way. The phenomenon of age hardening was discoveredin 1911, and since that time much research has been car­ried on in all parts of the world on various alloy sys­tems.

Age Hardening of Silver-Platinum Alloys

The alloy system selected for study was the binary alloy of platinum and silver. An examination of the various silver alloy diagrams revealed that of several possible alloys, the silver platinum was the most suit­able with regard to solubility.

An Experimental Investigation of the Age Hardening of Nickel with Boron

Since 1911, at which time, the age hardening phenomenon of duralumin was discovered by Film, much re­search has been carried on investigating the various alloy systems. The successful application of age hardening to the copper aluminum system (duralumin) has indicated the possibility of hardening practically all the metals in the same way.

Occurrence and Origin of Placer Gold in Montana

From time immemorial man has used gold as a medium of exchange, a mea­sure of value, as jewelry and for ornamentation. Placer gold has led dir­ectly or indirectly to the settlement of lands, California and Alaska being the two best known examples. It has led the way to the discovery of other important mineral wealth, the discovery of the copper and silver deposits at Butte, Montana and the discovery of the silver deposits at Cripple Creek, Colorado being two good examples.

Refining of Low Grade Zinc-Gold Precipitates

The purpose of this investigation was to ascertain if advantage could be taken of the copper in the precipitates as a collecting agent of the precious metals in the direct smelting furnace.The products produced to be low grade anode bullion and a slag low in precious metals, high in zinc and lead.

The Theory of Alloy Deposition and The Effect of a Rotating Cathode Upon Such Deposition, with Special Attention to the Possibility of Depositing Sterling Silver

In the past few years a great deal of atten­tion has been given to the electrodeposition of alloys. For the main part, this investigation has been of scien­tific interest only; but in a few instances, such work has attained commercial importance.

Precipitation of Gold, Silver, and Copper from Cyanide Solutions on Activated Charcoal.

Charcoal has been known for a considerable length of time to have the property of recovering gold, silver, and copper from cyanide solutions of these metals. Quantita­tive data that may shed light on the mechanism of the re­moval of these metals is very limited except that char­coal in a form known as activated has the power to abstract gold and silver in considerable quantities from the above solutions.

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.

An Investigation of Age-Hardening in a Commercial Copper-Beryllium Alloy

This investigation is concerned with the age-hardening process as exemplified by the aging of a commercial Cu-Be alloy and, in particular, with this pro­cess as determined by X-ray methods. The amount of infor­mation available on age-hardening of commercial alloys is scanty and what information there is, is inaccurate.

The Electrolytic Deposition of Chromium Upon Aluminum

The purpose or this investigation is primarily to determine the best conditions for plating chromium on aluminum. The work was carried out with the hope of obtaining coherent deposits, and of determin­ing the conditions under which such deposits may be duplicated.

The Electrical Resistance of Metals in their Hard and Soft States

Many investigations have shown that the electrical resistance of soft annealed metals is usually smaller than that of metals in their hard, cold worked state. By annealing cold-worked metals, the electrical resistance decreases to a minimum and then increases upon continued annealing at higher temperatures. The work performed in this investigation upon silver, aluminum, copper, nickel, and soft steel corroborates this idea.