Step 3: Melt the Mixture|
Once the mixture has been transferred to the heating vessel, the sample is ready to be dissolved. A mould release agent, such as ammonium iodide may be added to the dry powder just before melting. The halide mixes with the sample and helps the mixing, ensures the complete transfer of melt from the crucible to the mould and helps the finished bead release from the mould as it cools.
The melting is gradual and mixing takes place via the agitating cradle holding the crucibles. In an electric, radiant-heat machine, like our fusion machines, the fusion can easily be accomplished between 1050°C - 1100°C for any fusible sample, with minium loss of volatile elements and less aging of the platiumware.
A surface tension modifier (iodine gas) may be applied during the fusion process via the iodine injector system, available on the Beadmaster. The atmosphere in which the fusion takes place can be modified to be oxidising or inert using the automatic atmosphere control option. The average time taken for fusion is between 10 and 20 mins, depending on the sample.