Orplid GK

Type 4
yellow / Au 73.8 
palladium-free

Composition: Au 73.8 / Ag 9.2 / Pt 9.0 / Cu 4.4 / Zn 2.0 /
In 1.5 / Ir 0.1
Standard: DIN EN ISO 22674 and DIN EN ISO 9693
Colour: yellow
Melting range °C: 970–910
Soft annealing: 15 mins at 800 °C / quench in water
Hardening: 15 mins at 400 °C / air
Preheating temperature °C: 700
Casting temperature °C: 1120
Further heating after melting (secs): electr.: 15–20
inductive: 5–8
flame: 5–8
Density g/cm3: 16.6
CTE 25°C–500°C (µm/mK): 16.2
CTE 25°C–600°C (µm/mK): 16.6
Soldering before firing: Orplid Ceramic solder 880
Soldering after firing: Orplid solder CF 720
Vickers hardness (HV 5/30): w: 150
a: 250
g/b: 205
0.2% proof stress (MPa): w: 340
a: 625
g/b: 445/505
Elongation at break (%): w: 28
a: 15
g/b: 15/15
Spruing: Following the rules for dental applications (see General Instructions for Use)
Investment: Phosphate-bonded investment materials (Cehacast P or Cehacast Speed)
Preheating: 700 °C, 30 to 120 mins until end temperature, depending on size of mould
Casting: 1120 °C, possibly increase by 20°C–30°C for resistance-heated vacuum pressure casting. Graphite crucible or open flame with ceramic crucible
Finishing: With carbide burs and/or ceramic-bonded stones. Always grind in one direction only! Sandblasting at a flat angle, using 50–125 µm aluminium oxide. Pressure should not exceed 2 bar
Cleaning: Steam jet cleaning or boiling in distilled water
Oxide firing: 5 mins at 780°C without vacuum. Afterwards, always clean in a preheated acid bath, e.g. Neacid, (for 10 mins) or sandblast with 50–125 µm aluminium oxide. Pressure should not exceed 2 bar. Clean thoroughly with a steam jet
Soldering before firing: Orplid Ceramic solder 880
Soldering after firing: Orplid solder CF 720
Firing: For highly expanding ceramic materials (e.g. CeHa WHITE® LF)