Division Watches and Jewelry	Data sheet for alloy
	Au 750/3157 Pd
	Colour	white	Code	3157

General description	18 ct white gold nickel-free alloy containing Pd, for lost wax casting.

Physical properties	Specific gravity [g/cm3]	15.2	Melting range [°C]	910-955

Mechanical properties			Annealed	20% cold worked	75% cold worked
Vickers hardness		[HV1]	180	265	280
Yield hardness	Rm	[Mpa]	585	800	1060
Elastic limit	Rp0.2	[MPa]	385	600	900
Plastic elongation	A	[%]	30	2	1

Processing guidelines
ANNEALING	650 °C for 20 to 30 minutes then quenched in water. In order to avoid oxidation, work under reducing atmosphere.
COLD WORKING	The amount of coldwork completed before annealing should be between 30% and 75% reduction in area.
SOLDERING	By torch or furnace. The nickel-free solders N° 3534 (750-810 °C) and 3535 (650-780 °C) are strongly recommended. For alternatives please see list of solders.
PICKLING	with DESOXYD (following operating instructions) or with hot 10% sulphuric acid added to hot 10 g/l ammonium persulphate. The slight change of colour which could appear can be removed by polishing.
CASTING	Quench the cylinder just after removing from the casting furnace to keep malleability to a hardness of 180 HV instead of 210 HV. Do not mix or solder with Ni-alloys. The alloy can be recycled.
PATENT	US 6,342,182 B1 - EP 1 245 688 A3

18.03.2005

METALOR Technologies SA - Av. du Vignoble - CH-2009 Neuchâtel Phone: +41(0)32 720 61 11 - http://www.metalor.com/watch

20.04.2000

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