Key Advantages of 1.2:2.2 over 100% lithium tetraborate X-Ray Flux
- 1.2:2.2 dissolves silica easily whereas silica is difficult to dissolve with 100% lithium tetraborate.
- The addition of lithium metaborate to the 1.2:2.2 x-ray flux formulation decreases the temperature of fusion and therefore permits better homogeneous dissolution of the oxides in the melt.
- When using 100% lithium tetraborate the selected fusion temperature is required to be 150 - 200°C higher than the fusion temperature of the flux used in order to maintain a very homogeneous solution. With 1.2:2.2 having a significantly lower fusion temperature than 100% lithium tetraborate the heating apparatus and the platinum ware life is greatly prolonged.
- The lower fusion temperatures with 1.2:2.2 means that the loss of volatile elements such as sulphur and volatile oxides such as Na2O, K2O and SO3 is reduced.
- The fusion temperature must be less than 1250°C to avoid evaporation of Li2O and this is much easier to achieve with 1.2:2.2.
- Bad dissolution during fusion causes crystallisation and cracking of the glass discs. By using 1.2:2.2 the temperature range for fusion is much wider therefore there is a decreased chance of disc problems.
- Bubbles in the middle of the bead are the result of too low fusion temperature. Compared to lithium tetraborate, 1.2:2.2 flux has a much wider fusion temperature range between the temperature at which bubbles will be avoided and volatiles being lost.
- Using lithium tetraborate the fusion temperature range between avoidance of bubbles and loss of volatiles is much less than by using 1.2:2.2.
- The particle size range of 1.2:2.2 is designed to make optimum contact between the sample and flux achieving better dissolution over opposition products together with the elimination of dust (health hazard).
- Sodium nitrate added to the 1.2:2.2 flux formulation is screened to be the same particle size as the 1.2:2.2 flux thereby ensuring homogeneity within the flux /sodium nitrate mixture.
