UGIN DENTAIRE
DUCATRON QUATTRO
Rev. 080119
19
USING CRUCIBLES
The DUCATRON Quattro is delivered with two types of crucible and a vitrified carbon sleeve.
– SILICON CARBIDE CRUCIBLE (grey)
It can be used for non-precious metals.
Its composition means it can be used up to temperatures of 1500°C to 1600°C.
The silicon carbide helps prevent the tongue formed during injection between crucible bottom and lip
sticking to the crucible.
– SILICA CRUCIBLE (white)
It can be used with precious and non-precious alloys. Its maximum operating temperature (1400°C à
1500°C) is less than that for silicon carbide crucibles.
On the other hand, its cost price is lower.
– VITRIFIED CARBON SLEEVE (or vitreous carbon)
Designed for using precious or semi-precious alloys, it can be used with of silica crucible.
Being smooth it protects the alloy from any contamination by cup components.
PLEASE NOTE!
Never use the vitrified carbon sleeve for fusing non-precious alloys.
ADVICE ON USING CRUCIBLES
Casting incidents are generally linked to the choice or condition of crucible used, in terms of possible
fissures, distortion or wear. To avoid such problems, it is recommended to respect some simple rules:
1.
Check on the type of crucible recommended by the alloy manufacturer. If no particular is detailed,
use cups mentioned above.
2.
If the crucible has already been used, check its condition.
3.
Watch over the fusion process constantly to avoid any alloy overheating.
Any prolonged holding of the fusion temperature brings about distortion and premature cup wear
(Fig. 1).
Distortion
Silica transforms into
silicon dioxide
(cristobalite)
FIG 1
