sources for Argentium Silver info include:
My site: http://www.cynthiaeid.com
Trevor's site: http://www.touchmetal.com/blog/argentium-blog.html
Marty Andersen's site: http://argexp.blogspot.com/
Following are two info sheets: the AS 925 casting info sheet from
Stern-Leach, and a section from the Argentium Silver Co.'s sheet. I
think they cover all the topics you asked about, except for any
mention of vacuum casting. I can probably find out for you---what
exactly do you want to know about vacuum casting that is not covered
in the following
Argentium[tm] Casting Grain
DESCRIPTION: A new tarnish and fire scale resistant casting alloy
which can be age hardened twice as much as regular sterling silver.
FORM: Argentium[tm] grain comes as roughly spherical particles
ranging from 1.75 to 4.75 mm in size.
ITEM NUMBER: G6646, G6654 (Bright Cast)
COMPOSITION: 93% Silver
DENSITY: 5.41 troy ounces/in3
SOLIDUS: 1410 F (766 C)
LIQUIDUS: 1610 F (877 C)
CASTING: When investment casting, a pour temperature of 1740-1780 F
(950-980 C) and a flask temperature below 1250 F (677 C) is
recommended. If casting without a protective atmosphere, the use of
boric acid flux or graphite powder is effective. After casting the
metal, a minimum of 15 minutes air cooling is required before
quenching. Investment may be easily removed with water spray,
ultrasound, and pickling solution.
POLISHING: To avoid contamination from other alloys in the workshop,
a separate wheel should be used for Argentium[tm] sterling only. If
this is not possible, thoroughly rake wheels before use. After
polishing, heat the castings in an air atmosphere to 250 F for 10
minutes to activate the germanium oxide layer which is highly tarnish
HARDENING: Typical hardness of rapidly quenched pieces is 70 DPH.
Flasks cooled to room temperature can approach 110 DPH and heat
treated castings can approach 125 DPH! (Approximately twice the
hardness of standard Sterling silver!). To obtain this hardness,
place the castings in the oven at 580 F for 45 minutes.
SOLDERING: Argentium[tm] Sterling displays a lighter color when
heated. If the metal looks yellow or light orange, it is too hot. It
is important to avoid overheating this metal.
REMELTING: Remelting scrap may result in brittle castings.
Warranty Clause: Stern-Leach believes this data to be accurate and
reliable. However, these are recommenda=ADtions only given free of
charge and should be employed by you with discretion and risk.
Stern-Leach assumes no responsibility for difficulties or damages
incurred by adhering to this
Casting specs from Argentium Silver Co.:
Casting temperature range
1750-1800 F / 955-980 C. Argentium=99 Sterling Silver displays a
paler color when heated/molded, therefore the casting temperature
cannot be judged by eye.
Lower flask temperatures are recommended. For guidance, drop by a
minimum of 85 F / 30 C below regular temperatures used for standard
Successful castings have been made using the following flask
700-800 F (370-425 C) for heavy castings and 800-1000 F (425-535 C)
for light castings.
To avoid contamination from other alloys, it is important to use
separate crucibles for Argentium Sterling Silver. Do not use silicon
A protective atmosphere is recommended when melting Argentium=99
Sterling Silver. If a protective atmosphere is not available, flux
can be used (boric acid is recommended). Skim any oxides off the
surface before stirring.
Hardness wet investment removal
Leave flasks to cool for 20-25 minutes before quenching. This will
give castings approximately the same hardness as standard sterling
silver (70HV). To raise the hardness to approximately 95HV, heat
castings at 580 F / 300 C for 30-45 minutes and air cool to room
Hardness dry investment removal. Leave flasks to cool to room
temperature before removing castings from the investment. This will
give Argentium Sterling Silver a hardness of approximately 100HV.
For hardness above 100HV, follow precipitation-hardening
Use at least 50% fresh / 50% scrap mix. For high-quality pieces,
using more fresh metal will yield superior results. It's important
that used trees and buttons are free from investment powder residue
to avoid contamination.