Heat Treating Gold And Silver

General News, Instructions, Technical Articles

Heat Treating (Hardening) & Annealing (Softening)

14KY#75ND Yellow Heat Treatable Gold

Heat treating is a two step process that includes softening first.

First, form your product.

Then, in a controlled atmosphere oven (or using a boric acid barrier in a regular burn out oven) heat your items to 1200 degree F. for 10 to 30 min.Then quench in ice cold water. This softens the metal to provide a initial soft phase to begin from. This assures consistency from batch to batch. If the initial hardness is not consistent, then neither can the end product be consistent..

Heat items to 680F. in the same oven, in the same manner, for up to 30 min & quench in very cold (ice cold) water

A local trick we learn in Los Angeles is to quench into “blue alcohol” which is denatured alcohol with boric acid added. Commonly available at tool supply houses. This also cools the items very fast. Fast, consistent cooling ensures consistent results.

14KWhite & 18KWhie Sheet Gold Rolling Procedure

Melt your white gold & pour into a steel mold that has been pre-heated to 200F to 300F.

Let the ingot cool in the mold until cool enough to handle.

Roll to a reduced thickness of at least 30%, but not more than 50%.

If additional reduction is needed, anneal (soften) as follows…

A. Pre-heat an oven to 1125F, then place your gold bar in the oven for 20 minutes.

B. Remove bar from oven & air cool.

C. Continue rolling sheet. If more than 40% reduction is needed at this point, re anneal according to instructions.

Sterling Silver Heat Treating and Annealing

Annealing Sterling is similar to other alloys. Protect the surface with either a flux or use a controlled atmosphere oven. The ideal temperature to anneal (soften) sterling is between 1100F. & 1200F. Hold this temp for a few minutes and then quench in water. To heat treat (harden) Sterling, heat to 650F. for up to 2 hours to reach maximum hardness.