Hardness, durability and simple heat-hardening properties
The importance of hardness and traditional methods of hardening sterling silver
Heat-hardening Argentium Silver: the benefits of a simple heat treatment
Heat-hardening Argentium Silver flutes
Related documents
The importance of hardness
Silver alloys are required to be soft and malleable when applying forming, shaping and drawing processes; however, it is important that finished articles are hard and durable, so that the metal is not vulnerable to damage from scratching, denting and deformation.
Traditional methods of hardening sterling silver include:
Work hardening: through physical manipulation of the metal (e.g.: hammering, bending, forming, etc.).
Precipitation hardening: this involves rapidly cooling (quenching) the metal from red heat. This is not suitable for soldered or delicate items.
^ Top
Heat-hardening Argentium Silver - even soldered and delicate articles can be easily hardened by a simple heat treatment!
Germanium imparts unique hardening properties to sterling silver. Heat treatments at temperatures achievable in domestic ovens, can increase the hardness and durability of the Argentium Silver alloys. Argentium 930 Silver can be heat treated to almost twice the hardness of annealed standard sterling silver. The simple heat-hardening process does not require a rapid cool (quench) from red heat. This means that even soldered and delicate items (like the Argentium Silver flute below), can be easily hardened after construction. Click here for heat-hardening instructions.
Castings can be simply left to air-cool to room temperature to develop good hardness and durability. Information about heat-hardening castings can be found in the Investment casting section.
^ Top
Heat-hardening Argentium Silver flutes
Traditional sterling silver flutes are constructed using low-temperature lead/tin solders, as the higher temperatures required for silver solders would irreversibly soften the instrument. The low-temperature solders can, however, break down over time and leak air, which is detrimental to the performance of the instrument.
The Argentium 930 Silver flute (left) was made by Landell Flutes (USA). Silver solders have been used to make the instrument and a simple heat-hardening procedure was applied to the flute after construction - ensuring durability and enhancing the performance, projection and sound of the instrument.
Image: Argentium 930 Silver flute, by Landell Flutes
"As to the sound of the Argentium Silver flute, I find that it has greater power and projection than a similar flute made in traditional sterling and the power and projection rivals that of titanium, while retaining all the modesty and traditional sweetness of sterling... I hear a 'core' in the tone that is really beautiful." - Jonathon Landell (flutemaker)
^ Top
Related documents
'Hardness, durability and heat-hardening Argentium Silver' data sheet (pdf download)
'Why does hardness matter in jewellery alloys?' by Charles Allenden (pdf download)
^ Top