 #391
Alloy
Thank you for using UNITED'S alloys.
UNITED'S 391 ALLOY is designed for 18K - 22K yellow gold casting,
which produces a deep yellow color, popular in the middle-east.
You should obtain excellent results by following a few simple
instructions.
MELTING
| Melt Temperature for 18K Alloyed Grain |
1000° - 1010° C |
1832° - 1850° F |
| Melt Temperature for 20K-22K Alloyed Grain |
1100° - 1130° C |
2012° - 2066° F |
| Melt Temperature for Alloying 18K |
1070° - 1080° C |
1958° - 1976° F |
| Melt Temperature for Alloying 20K-22K |
1080° - 1100° C |
1976° - 2012° F |
We do recommend pre-graining all alloy and fine gold before
casting to assure a uniform mixture.
FLASK TEMPERATURE
| For 18K |
use normal recommended temperature |
| For 20K-22K Vacuum casting |
676° - 730° C |
1250° - 1350° F |
| For 20K-22K Centrifugal casting |
537° - 565° C |
1000° - 1050° F |
FLUXING
Boric Acid is the recommended flux. Use as little flux as
possible. Do not use carbon fluxes or any fluxes designed for
refining; i.e., soda ash, saltpeter, etc. Avoid flux in bottom pour
automatic casting units.
QUENCH TIME
15-20 minutes.
INVESTMENT REMOVAL
Most standard investment removers will successfully remove
the investment powder. Fluoric-based investment removers are the
best for removing the silicon oxide invisible coating. Our Brite-Cast
Investment Remover also works very well.
REMELTING
We recommend 50% rejuvenation for remelting.
NOTES
Melt temperature may vary with type of unit. This alloy is
designed for casting only.
TECHNICAL ASSISTANCE
Always available…
Call 1-800-999-3463 / 1-800-999-FINE
E-mail / doc@unitedpmr.com
Web-Site / www.unitedpmr.com |