ECO 52

Type 4
light yellow / Au 52.0
copper-free

Composition: Au 52.0 / Ag 29.0 / Pd 12.5 / In 4.5 / Zn 1.4 / Sn 0.5 / Ir 0.1
Standard: DIN EN ISO 22674 and DIN EN ISO 9693
Colour: light yellow
Melting range °C: 1080–970
Soft annealing: 20 mins at 800 °C
Hardening: 20 mins at 500 °C
Preheating temperature°C: 750
Casting temperature °C: 1200
Further heating after melting(secs): electr.: 20–30
inductive: 5–8
flame: 5–8
Density g/cm3: 14.0
CTE 25-500 °C (µm/mK): 16.5
CTE 25-600°C (µm/mK): 16.8
Soldering before firing: Orplid Keramik Lot CF 950
Soldering after firing: Orplid Lot CF 720
Vickers hardness (HV 5/30): w: 150
a: 235
g/b: 205/235
0.2% proof stress (MPa): w: 325
a: 510
g/b: 440/570
Elongation at break (%): w: 11
a: 5
g/b: 5/6
Spruing: Following the rules for dental applications (see General Instructions for Use)
Investment: phosphate bonded investings
Preheating: 750 °C, 30 to 90 min at end temperature, corresponding to muffle size
Casting: 1200 °C; if using resistance heated casters possibly increase on 20-30 °C. Graphite crucible resp. ceramic crucible.
Finishing: with carbide milling and/or ceramic bonded abrasives. Take care to ensure always to use the same direction of rotation! Sandblasting with 110 -150 μm aluminium oxide particles. Pressure may not exceed 2 bar.
Cleaning: clean with steam device or boil in distilled water.
Oxide firing: 10 min at 800 °C with vacuum.
Soldering before firing: Orplid Keramik Lot CF 950
Soldering after firing: Orplid Lot CF 720