What is fusion technique, how does it work and what are the benefits?

What is fusion technique?

Fusion is a technique for preparing samples for analysis with X-Ray Fluorescence (XRF), Inductively Coupled Plasma (ICP) or Atomic Absorbtion (AA). This allows the composition of chemical elements to be determined.

In fusion, the sample is first pre-processed for further analysis. The ground sample is mixed with a flux (lithium or sodium) in a platinum or platinum/gold crucible (often 95%/5%). Then the crucible is heated to around 1000°C with fusion machine and stirred, causing the sample to dissolve in the molten flux. This creates a nice homogeneous melt.

Fusion for XRF analysis

In XRF analysis, the mixture (the hot borate melt) is then poured into a platinum bead container and cooled. This creates a glass bead which can be measured directly with the XRF spectrometer.

For what tests is XRF analysis used?

Examples of tests are cement, steel, glass, ceramics, fossil fuels, (precious) metals, fertilizers, environment, pharmaceuticals, nuclear, geology and more.

Why fusion for XRF analysis?

In XRF analysis, samples can also be pressed into pellets. So why use fusion? As mentioned earlier, fusion properly mixes the particles of the sample with the borate flux, giving you a homogeneous glass bead to perform your XRF analysis on.

The big advantage:

  • It leads to highly accurate repeat analysis results.
    This is because the X-rays are not affected by different sample particles in different sizes being randomly dispersed, as is the case with pressed pellets.
  • No matrix effect
    With fusion, the matrix (glass) remains consistent. It does not affect the analyses and leads to accurate results. It also allows for easy calibration with synthetic standards.

Fusion for ICP analysis

In ICP analysis, the mixture (the hot borate melt) is poured into beakers containing dilute acid. This produces a solution that can be measured directly.

For what tests is ICP used?

Examples of tests include: sand, clay and other silica-containing samples, all oxides, catalysts, precious metals and alloys, polymers, fly ash, pharmaceuticals and more.

Why fusion for ICP analysis?

The sample can also be properly prepared for ICP analysis by fusion. This offers a number of advantages:

  • Effective and fast
    Fusion dissolves samples within minutes. Dissolving samples by acid digestion can take hours and many types of acids are required.
  • Safe and clean
    Fusion does not require the use of dangerous acids such as HCI04 or HF. This increases safety in the laboratory. It also simplifies waste management because no protective clothing and special laboratory hoods are needed to perform fusion . This also saves on costs.
  • Dissolving many types of samples
    Many types of samples can be processed for complete and rapid dissolution, including refractory samples such as alumina- and silica-based materials.

Read more about the maintenance of platinum crucibles, dishes and molds used being used fusion analysis.

Our products for fusion analysis

View our range of (precious metal) products for fusion (fusion) technique.

Laboratory items for XRF analysis

Fusion machines for XRF analysis

Crucibles and trays for fusion analysis

Fluxes for XRF, ICP and AA analysis