Accurate measurement of hydrogen in the melt before casting is crucial

Aluminium alloys absorb hydrogen while in their liquid state, which, if not effectively removed, results in porosity within the final casting. Accurate measurement of hydrogen in the melt prior to casting is crucial for ensuring that degassing processes meet the required quality acceptance standards.

The origin of hydrogen in molten aluminium primarily stems from the chemical reaction between aluminium and water: 2Al + 3H₂O 4 Al₂O₃ + 3H₂ . Atmospheric water vapour is one major source of this reaction; additional sources include combustion products from gas or oil-fired melting processes, hygroscopic materials used for degassing or fluxing, reactive substances in the melt, and hydrated corrosion products found on feed materials.

Hydrogen formed through these interactions becomes absorbed in the molten aluminium. If adequate degassing techniques are not employed to minimize hydrogen content, its presence leads to the formation of porosity in the casting. Accurate measurement of hydrogen in the melt prior to casting is crucial for ensuring that degassing processes meet the required quality acceptance standards.

This essential measurement is performed directly on the foundry shop floor using the Hyscan II Hydrogen in Aluminium Analyser, developed in the UK by MechaTech Systems Ltd.

Hyscan II delivers a precise measurement of hydrogen in the melt within five minutes of sampling.

The Hyscan II employs a quantitative reduced-pressure technique to monitor hydrogen levels during aluminium alloy processing. It delivers a precise measurement of hydrogen in the melt within five minutes of sampling.

Hyscan II features a robust design tailored for the demanding environment of the foundry floor

Engineered with durability in mind, the Hyscan II features a robust design tailored for the demanding environment of the foundry floor. It is simple to operate, mobile, and highly reliable, offering proven accuracy with less than a 5% variance compared to the vacuum sub-fusion method.

Beyond its role in quality control, the Hyscan II serves as an invaluable tool for process investigation and the assessment of melt treatments. Its application contributes to lower scrap rates and reductions in energy and labour costs. These savings often enable the capital investment in the instrument to be recouped in under a year.

This reliable method for evaluating porosity in aluminium castings has established the Hyscan II as a global leader, widely adopted by production foundries around the world.

Find out more about Hyscan II Hydrogen in Aluminium Analyser on our website: https://www.mechatechsystems.co.uk/hyscan-analyser;

Please contact us for any further information and a quotation.