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 Age Hardening of Copper with Manganese Silicide.

The increase in hardness is attributed to the manganese silicide being precipitated from solid solution and deposited between crystal planes. The subsequent softening which occurs on prolonging the period of reheating is believed to be due to an agglomeration of the dispersed hardening agent.

The Electrodeposition of Iron-Manganese Alloys

Various electrolytes were experimented with in an attempt to deposit an iron-manganese alloy. An Alloy was obtained from a solution containing ferrous ammonium sulfate, manganous sulfate, and ammonium sulfate. Further experimentation was done in an effort to determine the optimum conditions of deposition and the highest manganese alloy which could be produced.