Quenching silver, including argentium

Here is what I do in order to know when it is safe to move or quench
any sterling silver alloy -including Argentium Sterling: I drip a
little water onto the metal. If the water dances around on the metal
as droplets, then the metal is too hot to move or quench. If the
water sizzles when it touches the silver, then it is cool enough to
quench. I developed this habit years ago, before AS was developed,
after seeing problems from SS being quenched when too hot. Argentium
Sterling cools more slowly than traditional sterling because
germanium is a semi conductor— therefore your work stays hot
longer than usual, and may be hotter than was realized when it was
quenched.

Cynthia Eid

Hi Cynthia,

I developed this habit years ago....after seeing problems from SS
being quenched when too hot. 

What problems have you seen in SS when quenched hot? I always quench
hot silver (SS and 960) in hot pickle with no problems. Are you
perhaps referring to quenching hot metal in cold pickle?

Janet in Jerusalem

Hello Janet

At the Birmingam School for Jewellery I was taught to quench silver
in cold water. During the process of raising an object it will need
to be annealed several times to maintain malleability. The trick is
to allow the metal to cool slightly to black heat and then quench in
cold water. This stops the crystalline structure of the metal from
growing. If it is allowed to cool naturally the crystal stucture
grows and eventually the metal will start cracking. Never quench,
particularly large object, in acid pickle, it is dangerous. The spray
from hot acid is not good for you, others or your tools and
equipment.

Cheers
Hamish

Hello Janet,

Some commercially produced sterling silver uses copper-phosphorus to
deoxidise the silver prior to continuous casting for sheet and wire
production. The residual phosphorous level in the sterling silver
should be about 35ppm but can be much higher. At torch annealing
temperatures this has the potential to result in an alloy which is
hot-short if it is quenched to quickly; most commercial sheet and
wire production is furnace annealed at much lower temperatures than
that used when torch annealing.

Charles Allenden

Please define hot-short, it is a term I have not heard before…

Thanks!

Please define hot-short, it is a term I have not heard before... 

Basically in means that the metal is brittle when it is hot. So
bending or forging or in the case of a very hot short material like
Argentium just moving it while hot can fracture the metal. As
Charles said when you have too much phosphorous remaining in the
Sterling from improper manufacturing controls standard sterling will
become so hot short that it will fracture if quenched from a high
heat. I have had this happen to me once it was quite frustrating. It
is also why hot forging standard sterling is risky business.

James Binnion
James Binnion Metal Arts