Argentium 960-Pure User manual

Argentium User Guide
Argentium 960-Pure
Argentium User Guide - Argentium 960-Pure - produced for Argentium International Limited February 2012

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Contents
Heating, quenching and pickling ......................... Page 3
Heating applications and heat/colour recognition
Quenching
Pickling
Forming and decorative techniques .................... Page 4
Forming
Machining and engraving
Granulation and Keum-Boo
Patination
MokuméGane
Heat-hardening treatments ................................. Page 5
Method 1 - air-cooling
Method 2 - quenching
Joining techniques .............................................. Page 6-7
Soldering
Fusing
Welding
Investment casting .............................................. Page 8
Finishing processes ............................................ Page 9-11
Optimising tarnish resistance
Degreasing and rinsing
Manual polishing
Mechanical polishing
Surface passivation
Long term care ................................................... Page 12
Argentium 960-Pure
A premier grade, luxury alloy suitable for items produced from sheet, wire and tubing. It has
excellent machining properties and can be used for smaller scale casting applications.
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Look for this sign for useful/important information to remember about Argentium silver.

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Heating, quenching and pickling
Heating applications and heat/colour recognition
Argentium silver displays a paler colour glow than traditional sterling silver at red-hot temperatures.
Torch and furnace annealing do’s
Carry out torch annealing and soldering procedures in a shaded area to prevent overheating.•
Make sure your Argentium silver is securely supported whilst heating.•
Wait until the red glow has disappeared from your Argentium silver before touching or moving.•
Recommended furnace annealing temperature: 600-650°C/1112-1202°F for 20-45 minutes•
(dependent on the thickness of the material being annealed).
When furnace annealing using a protective atmosphere, it is important that the furnace gas does not•
deplete the germanium oxide surface layer as this will diminish tarnish and firestain resistance. Use
inert furnace atmospheres (i.e. nitrogen or argon) or an atmosphere containing maximum 5-10%
hydrogen in nitrogen.
Don’ts
Do not touch, move or manipulate Argentium silver while it is at red heat, as this may cause•
cracking.
Be careful not to overheat.•
Furnace atmospheres containing more than 10% hydrogen are not recommended.•
Quenching
Argentium silver retains its heat for longer than traditional sterling.
Do’s
After annealing, wait for the red glow to disappear before quenching (best judged in a shaded area).•
Always quench in water.•
Don’ts
Do not quench Argentium silver too quickly as cracking may occur.•
It is hazardous to quench metals in pickle solutions.•
Pickling
Recommended pickling solutions:
Sodium Bisulphate•
Weak Sparex•
Phosphoric Acid•
Sulphuric Acid•
Do’s
Dilute pickle solution as advised by the supplier.•
Heat pickle solution to recommended working temperature.•
Use pickling solution that is not over-used.•
Don’ts
Do not use Hydrofluoric Acid with Argentium silver• - Hydrofluoric Acid dissolves the protective
germanium oxide and diminishes tarnish resistance.
Do not use old or over-used pickle as the strength of any pickling solution will reduce with use and•
saturated solutions can leave unwanted deposits on immersed items.

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Forming
Ductility is an important property in any alloy that is required
to be shaped and formed by operations including spinning,
stamping, raising, drawing and hammering.
Argentium 960-Pure has greater ductility than traditional sterling
silver - this means that the metal can be worked longer and
further between each annealing, thus decreasing manufacturing
time and labour.
Hardness and durability are not compromised by the ductile
properties.
Machining and engraving
Argentium 960-Pure has very good machining and engraving
properties. Unlike traditional sterling, Argentium is not ‘sticky’
and will cut cleanly with a bright, sharp finish.
Granulation and Keum-Boo
Argentium 960-Pure’s fusing properties enable techniques such
as granulation and Keum-Boo to be applied.
Instruction DVDs by Ronda Coryell are available to purchase.
Each DVD beautifully demonstrates how to carry out different
processes with Argentium, including fusing and granulation
techniques. Please visit rondacoryell.com or riogrande.com for
further information.
Patination
A dark, rich patina can be achieved with patinating solutions
including liver of sulphur.
The process takes a little longer than with traditional sterling
silver due to the tarnish resistant properties of Argentium.
Mokumé Gane
Argentium 960-Pure can be used for Mokume Gane.
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Forming and decorative techniques

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Forming and decorative techniques Heat-hardening treatments
Argentium silver can be formed into complex shapes in its fully soft condition and by means of heat
treatments have its hardness and durability increased.
Method 1 - air-cooling
Step 1
After annealing or soldering allow Argentium silver to air-cool to room temperature.
Step 2 (This step increases the hardness of Argentium 960-Pure by 20-30HV/DPH)
Heat Argentium silver in a furnace or oven at 300°C/572°F for 120 minutes, then air-cool to room
temperature.
Method 2 - quenching
Step 1
Torch annealing method: Heat Argentium silver to a pale-red annealing temperature, wait until the red
glow has disappeared then quench in water.
Furnace annealing method: The recommended temperature is 650°C/1202°F under inert atmosphere
(nitrogen or argon) or slightly reducing atmosphere (maximum 5-10% hydrogen) for 10-20 minutes.
Step 2 (This step increases hardness of Argentium 960-Pure by 55-65HV/DPH)
Heat Argentium silver in a furnace or oven at 300°C/572°F for approximately 120 minutes, then air-cool
to room temperature.
Important information
Hardness will differ between wrought and cast material.•
Lower temperatures can be used for Step 2 (minimum temperature of 220°C/428°F), with a•
corresponding increase in time.
Preheat the oven/furnace and supports to the required temperature before commencing the heat-•
hardening treatments.
Make sure that the oven is clean and free from chemicals and substances that may be detrimental•
to the heat treatment process.
Slight discolouration may occur during the heating processes - this can easily be removed using•
pickle.
Remember that Argentium silver glows a paler colour than traditional sterling silver at red-hot•
temperatures - it is recommended to carry out heating applications in a shaded area to facilitate
temperature/colour recognition and prevent overheating.
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Joining techniques
Soldering
Argentium solders have been developed to give a good colour match with Argentium silver - (Argentium
solders are available from Rio Grande - riogrande.com).
Do’s
Always make sure that surfaces are clean and degreased before soldering.•
Remember that Argentium silver glows a paler colour than traditional sterling silver at soldering•
temperatures - it is recommended that soldering applications should be carried out in a shaded area
to avoid overheating.
To minimise distortion of Argentium 960-Pure during soldering operations, it is recommended to•
carry out a pre-annealing step - simply heat the sheet to a pale-red annealing temperature and allow
to air-cool to room temperature.
Argentium silver can be brittle at red-hot temperatures - make sure that the silver is well supported•
during soldering applications and simply wait a few seconds for the red glow to disappear before
touching or moving.
Don’ts
Don’t quench soldered pieces as this can cause the solder joint to fracture.•
Be careful not to touch or move your Argentium silver piece too quickly after soldering as this can•
cause brittleness - wait until the red glow has completely disappeared.
Flux
Argentium 960-Pure is highly resistant to firestain, it is therefore only necessary to flux the seam to be
soldered rather than applying flux to the whole piece. The following fluxes are recommended (use as
directed by the manufacturer):
My-T-Flux (supplied by Rio Grande, USA)•
Battern’s Flux•
Prip’s Flux•
N.B. ‘Handy’ or ‘Easy Flow’ type fluxes can cause staining with Argentium silver.
Fusing
Unlike traditional sterling silver, Argentium 960-Pure can be easily fused - producing strong, clean joints
with the added benefit of not having to remove excess solder or having visible solder seams on finished
articles. Instruction DVDs by Ronda Coryell are available to purchase - please visit rondacoryell.com or
riogrande.com for further information.
Argentium 960-Pure will fuse with: Argentium silver, pure silver, gold and platinum.
Do’s
Thoroughly clean/degrease sections being fused.•
It is recommended to apply a diluted flux to the sections being fused.•
Heat the piece with a gas/air flame and work in a shaded area (this makes it easier to visualise the•
temperature by the colour/glow of the metal).
Argentium silver will glow brighter as the temperature rises - look for a ‘wet’ surface appearance as•
an indication of the correct fusing temperature.
Allow the red glow to disappear before touching or moving the fused piece.•
Don’ts
Be careful not to touch or move your Argentium piece too quickly after fusing as this can cause•
brittleness - wait until the red glow has disappeared.

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Joining techniques
Welding
The high conductivity and reflectivity of traditional sterling silver makes the alloy difficult to weld. The
small amount of germanium in Argentium 960-Pure increases the thermal and electrical resistance,
making the silver suitable for welding processes.
Advantages of welding
Welding applications offer efficient production methods, using localised heat for joining materials.
Welding technologies provide excellent alternatives to the use of solders.
The weldability of Argentium Original opens new avenues for the design and production of silverware
and jewellery items.
Measuring conductivity
The International Annealed Copper Scale (IACS) is a measure of conductivity in metals and alloys (lower
IACS values = increased weldability).
The chart below shows the IACS values for various metals and alloys.
Metal or alloy IACS value (%)
Copper 100
Pure silver 108
Traditional sterling 96
Argentium 960-Pure 68
Mild steel 25

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Investment casting Argentium 960-Pure
Argentium 960-Pure is suitable for smaller scale casting. For high volume casting, please use
‘Argentium Professional Casting’ alloys.
Flask burn-out
Allow the flask to stand for 2 hours before the burn-out cycle.•
Do not overload the burn-out furnace - this ensures that the centre of all the flasks will reach the•
required temperature for complete burn-out and that there is sufficient air-flow to remove moisture
from the cured investment powder.
Flask and metal temperatures
The following temperatures are for general guidance. Personal experience and knowledge of casting
equipment will enable judgement of the suitable flask and casting temperatures to use.
Size of object Metal casting temperature
(thinner object = hotter temp.)
Flask temperature
(thinner object = hotter temp.)
Thin: 0.2 - 0.5mm 1025-1005°C / 1877-1841°F 620-580°C / 1148-1076°F
Medium: 0.5 - 1.2mm 1005-990°C / 1841-1814°F 580-520°C / 1076-968°F
Thick: >1.2mm 990-970°C / 1814-1778°F 520-480°C / 968-896°F
Crucibles
Use separate crucibles to avoid contamination from other alloys.•
Clay graphite or pure graphite crucibles are recommended.•
Silicon carbide crucibles are not recommended.•
Accurate temperature control
Argentium silver displays a paler colour glow than traditional sterling silver when heated or molten.•
Accurate temperature readings are important to prevent overheating.•
Protective gas cover
Use an inert gas cover (i.e. argon or nitrogen).•
The cast flask should be held under the inert gas protection for 1 minute before removal from the•
casting chamber.
N.B. If a protective atmosphere is not available, flux can be used (boric acid is recommended). Skim
any oxides off the surface before stirring.
Removing flask from the casting chamber
After pouring the metal, remove the flask from the casting chamber within 1 minute.
Wet investment removal (suitable for castings without stones)
After pouring the metal, remove from the casting chamber within 1 minute and leave flasks to stand•
for 25 minutes before quenching in water.
Castings can then be hardened by heat treatments (see page 5).•
Dry investment removal (suitable for stone in place castings)
After pouring the metal, remove from the casting chamber within 1 minute and leave flasks to cool•
for a minimum time of 90 minutes before quenching in water.
Remove investment residues by jet washing in water, followed by pickling, then rinse with water (do•
not rinse in deionised water).
David Worcester

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Finishing processes
Optimising tarnish resistance
Optimum tarnish resistance of Argentium silver relies upon applying good practice for finishing
procedures. The aim of these finishing procedures is to optimise the formation of the protective
germanium oxide that gives Argentium silver its tarnish resistance.
Certain practices used in the trade with traditional sterling silver may harm Argentium’s protective
germanium oxide and care must be taken not to contaminate the surface of Argentium silver with other
metals/materials during polishing processes.
The following recommendations are a guide to achieving a beautiful lustrous finish with optimum tarnish
resistance.
Degreasing and rinsing
Argentium pieces should be ultrasonically cleaned, rinsed with tap water and thoroughly dried:
a) Between each polishing stage.
b) Before the final surface passivation heat treatment.
Ultrasonic cleaning process
For commercial operations it is recommended that the following cleaning process is used:
1) Degrease: Immerse pieces in an ultrasonic bath at 50°C (122°F) for 2 minutes using a 2% solution of
the ‘Argentium approved’ cleaner supplied by Legor Group (product code 4580511).
2) Rinse: Rinse with demineralised water at room temperature for 15 seconds.
3) Surface neutralisation: immerse in Legor ‘Argentium approved’ pickling solution (product code
4581516) for 10-15 seconds.
4) Rinse with demineralised water at room temperature for 15 seconds.
For smaller operations, again use an ultrasonic cleaner:
Cleaning solution: dishwashing detergents including Joy and Fairy can be used (ensure the pH of•
the cleaning solution is between 7-9)
Cleaning solution temperature: 40-60°C / 104-140°F•
Cleaning time: immerse pieces for 2-3 minutes•
Rinsing: rinse with tap water and dry thoroughly•
Important information
Do not rinse Argentium silver alloys with deionised/reverse osmosis water - the high purity of this water
can remove some of the protective germanium from the surface of Argentium, therefore reducing tarnish
resistance.
Steam cleaning and electrolytic cleaning should not be used with Argentium silver as these processes
can diminish tarnish resistance.
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Finishing processes
Helpful tip
After purchasing Argentium silver semi-finished products such as wire, chain and jump rings - even
though these items may look clean and bright it is advisable to refinish them (using either manual or
mechanical methods) to ensure optimum tarnish resistance.
Manual polishing
Important information
It is important to use separate polishing wheels, mops and compounds for Argentium silver to avoid
contaminating the surface with residues from other metals or materials - surface contamination can
diminish the tarnish resistance of Argentium items. If this is absolutely not possible, then polishing
wheels and mops must be thoroughly cleaned/raked before use.
The cutting (or dressing) stage requires the use of separate abrasive papers or wheels.
Mechanical finishing (3 stage process)
Stage 1 (optional)
Surface burnishing operation - to brighten ‘hard to reach’ areas of items using magnetic pins in a near-
neutral aqueous and soap solution (pH 7-9). Minimum time = 20 minutes.
Stage 2
Cutting and dressing operation - to smooth the surface using either one or a combination of the
following processes:
A ceramic or plastic media in a near-neutral aqueous solution (pH 7-9) - use as recommended by•
the manufacturer.
Manual techniques using abrasive wheels and papers.•
Stage 3
Polishing operation - to give a lustrous finish using either one or a combination of the following
processes:
A dry polishing media such as crushed walnut shell (use as recommended by the manufacturer).•
Manual polishing using polishing compounds with polishing mops/wheels/felts.•
Do’s
Use separate polishing media for Argentium silver to prevent cross contamination with other metals/•
materials.
Maintain clean polishing media and solutions.•
Clean and rinse items between each polishing stage.•
Thoroughly dry items after degreasing and rinsing.•
Don’ts
Do not use polishing media and solutions that have been used with other metals/materials - this can•
contaminate the surface of Argentium items and will diminish tarnish resistance.
Do not rinse with deionised water as this can damage the protective germanium oxide and diminish•
tarnish resistance.
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Finishing processes
Surface passivation - heat treatment
Argentium silver’s tarnish resistance relies upon a protective germanium oxide surface layer. It is
possible to assist the formation of this layer by applying a simple heat treatment to finished pieces.
After pieces have received their final polishing and degreasing/cleaning operations, heat them in an oven
in an air atmosphere at 100°C/212°F for 3-16 hours. No further polishing should be required provided
that the oven is clean. If the pieces require any additional cleaning after this process, follow the cleaning
instructions given on page 9.
Important information
Ensure that the Argentium silver finished items are thoroughly clean before heat treating. •
Preheat the oven to the required temperature before carrying out the heat treatment. •
Make sure that the oven is clean and free from chemicals and substances that may be detrimental •
to the heat treatment process.
Surface passivation - chemical treatment
As an alternative to the heat passivation process it is possible to chemically treat Argentium silver, which
allows the protective germanium oxide layer to develop naturally over a period of time underneath the
protective layer.
This treatment is particularly recommended instead of the heat passivation process where:
The manufacturing process does not allow the standard heat passivation process to be carried out.•
The local atmosphere is known or suspected to contain significant amounts of sulphurous•
compounds (e.g. areas where there are higher levels of pollution).
Treat the pieces with Legor Tenaris Pro in accordance with the manufacturer’s instructions. This
chemical passivation will protect the pieces from discoloration until a protective germanium oxide layer
has naturally developed.
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Long term care
Argentium silver is low maintenance, easy to care for
and simple to keep clean. Simply wipe away any dust
or finger marks with a soft cloth or, for more intricate
pieces, wash them in warm soapy water, rinse and dry
immediately to avoid water marks.
An occasional wipe with a clean silver polishing cloth
will help to maintain Argentium silver’s beautiful shine
and lustre (Goddard’s Long Term Silver Cloths and
Tiffany & Co. Mitts are recommended). Avoid using
coarse, contaminated or old cloths as they may impair
the surface lustre of Argentium silver.
Please do not use ‘dip’ polishes or electrolytic cleaning
processes with Argentium silver.
Important care advice
As recommended for other precious metals, it is
advisable to remove Argentium silver jewellery before
entering chlorinated or salt-water swimming baths/
jacuzzis and before carrying out activities where
Argentium could come into contact with chemicals.
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For sales and technical enquiries please email
[e-mail] or visit our website
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