A METHOD OF HEAT FREETING A COPPER-NICKEL-SILICON-CHROMIUM ALLOY

摘要

A method of heat treating a copper base alloy, consisting by wt. of 2.0% to 3.0% of a metal selected from the gp. consisting of nickel and cobalt and mixtures thereof, silicon in an amt. equal to or slightly in excess of the stoichiometric amt. necessary to form silicides of said metal, chromium in an amt. in excess of the stoichiometric amt. required to form chromium silicide with the excess silicon not combined as said metal silicides and the balance copper, comprises the steps of heating the alloy to a soln. temp., quenching the alloy, ageing the alloy at a first ageing temp. in the range of 482-593 deg.C, and ageing the alloy at a second ageing temp. in the range of 399-482 deg.C.