Ultra White, nickel based, high tensile strength, Does not contain silver. Does not contain gold. Recommended for making 14K to 18K white fabrication alloys. Also suitable for casting. Sold by the troy ounce (20 DWT).
Contains:
Cu 59.9%
Zn 20%
Ni 20%
Sold by the troy ounce (20 pennyweights or 31.1 grams).
Note: There are proprietary metals in the formulation which are not included in the composition section. May also contain silicon and deoxidizers.
Melting (Fabrication)
The 846-141 alloy and fine gold should be melted together in a clean crucible. Put the alloy in the bottom of the crucible and the fine gold on top. Initial melting temperature should be 1070 C/1958F. Drop the temperature somewhat before pouring as listed below. Boric Acid flux should be used to keep the metal clean during the melting process. The molten metal should be mixed well with a stirring rod before pouring to assure a good mix. A neutral or reducing cover gas is very helpful in melting white gold alloys.
Pouring Temps for Ingots:
14K 1010C/1850F
18K 1015C/1860F
Pouring
Metal should be poured into a preheated, vertical graphite, or lightly lubricated iron mold. A steady even pouring motion should be used, slowing down at the end of the pour to prevent shrinkage in the top of the ingot. Use a round rod mold for wire and a L shape 2-piece shaped mold for plate and sheet.
Don't Quench
Remove the ingot from the mold and allow to air cool-Don't Quench. Nickel white gold rolling alloys with be much softer if allowed to air cool after pouring and after annealing. Soak ingot in a hot pickle solution to remove surface oxides.
Fabrication
The metal ingot should be cleaned of all adhering oxide or fluxes before rolling. The ingot should be rolled or drawn to a 50% reduction in size before annealing. To small of a reduction can cause ingot to crack during anneal. After annealing continue the reduction at 50% before annealing again. Clean the ingot after each anneal in hot pickle solution. Keep the rolls, dies and metal clean to prevent defects in the finished stock.
Annealing
Annealing temperature: 732C/1350F for 20 minutes. Do not quench ingot, allow to air cool. A boric acid fire coat should be applied before annealing in an open atmosphere oven to protect the metal from heavy oxidation. Clean the ingot in hot pickle solution to remove surface oxidation after annealing. Avoid over annealing wire, plate or sheet stock as this can cause excessive grain growth creating orange peel surface or poor strength in finished goods.
Remelting
Use a 30% scrap to 70% fresh mix on nickel white gold alloys. White gold alloys have about 1/3rd the reusability of yellow gold alloys.
• Very little boric acid flux is recommended. Do not use carbon flux such as soda ash, saltpeter etc. No flux needed in bottom pour automatic casting unit. • Use of aggressive acid causes corrosion and surface damage. • To calculate the weight of the metal needed (in grams), multiply density (gm/cc) with weight of wax (grams) . Add 10% of the total weight for button. • Gypsum bonded investment is recommended. Follow manufacturers instruction for burnout cycle.
California Prop 65 Warning:
This product can expose you to chemicals including nickel, which is known to the State of California to cause cancer. For more information go to www.P65warnings.ca.gov.
