Type 4**
deep yellow / Au 73.9
palladium-free, copper-free
Composition: | Au 73.9 / Ag 14.0 / Pt 8.0 / Zn 3.0 / Rh 0.6 / Ta 0.4 / Ir 0.1 |
Standard: | DIN EN ISO 22674 and DIN EN ISO 9693 |
Colour: | deep yellow |
Melting range °C: | 1025-950 |
Soft annealing: | 15 mins at 750 °C / quench in water |
Hardening: | 15 mins at 500 °C / air |
Preheating temperature °C: | 750 |
Casting temperature °C: | 1180 |
Further heating after melting (secs): | electr.: 20–30 inductive: 5–8 flame: 5–8 |
Density g/cm3: | 16.6 |
CTE 25°C–500°C (µm/mK): | 15.9 |
CTE 25°C–600°C (µm/mK): | 16.3 |
Soldering before firing: | Orplid Ceramic solder CF 950 |
Soldering after firing: | Orplid solder CF 720 |
Vickers hardness (HV 5/30): | w: 130 a: 200 g/b: 170 |
0.2% proof stress (MPa): | w: 260 a: 505 g/b: 290/325 |
Elongation at break (%): | w: 24 a: 15 g/b: 20/16 |
Spruing: | Following the rules for dental applications (see General Instructions for Use) |
Investment: | Phosphate-bonded investment materials |
Preheating: | 750 °C, 30 to 120 mins until end temperature, depending on size of mould |
Casting: | 1180 °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 800°C–840°C without vacuum. Afterwards, always clean in an acid bath, e.g. Neacid, (for up to 5 mins) or sandblast with 50–125 µm aluminium oxide, at up to 2 bar pressure Clean (for 10 mins) in a preheated acid bath, e.g. Neacid, or sandblast with 50–125 µm aluminum oxide, at up to 2 bar pressure; clean with a steam jet |
Soldering before firing: | Orplid Ceramic solder CF 950 |
Soldering after firing: | Orplid solder CF 720 |
Firing: | For highly expanding ceramic materials; anneal for 15 mins at 500°C after glaze firing |