Tempered Beryllium Copper was developed by Little Falls Alloys to supply the springs industry with a Beryllium Copper wire that could be used on conventional coiling equipment to provide springs to close tolerance without the necessity of heat treatment. The advantages: Springs are not discolored by heat treatment, thus require no pickling and cleaning.

Springs are free of heat-treat distortion, giving close tolerance without expensive fixtures. Spring Coilers without heat treat facilities can supply Beryllium Copper springs. Pretensioned extension springs can be wound, which is not possible with heat treatable Beryllium Copper.

The disadvantages: Since the temper comes from cold work, the tempered wire spring is not useable at as high a temperature as heat treated Beryllium Copper. Tempered Beryllium Copper has been used in all applications listed for Heat Treated Beryllium Copper.