Measuring hydrogen in molten aluminium is essential to avoid porosity in castings. When aluminium alloys are in the liquid state, they absorb hydrogen. If this hydrogen is not removed, it can cause porosity in the casting.
Porosity is a defect in aluminum casting that can cause a number of problems, including:
Reduced strength and durability
Increased susceptibility to corrosion
Reduced machinability
Increased weight
Visual defects
Hydrogen in molten aluminium and its alloys derive principally from the aluminium – water reaction: 2Al + 3H₂O 4 Al₂O₃ + 3H₂ .
Water vapor is a major source of porosity in aluminum castings. It can come from the atmosphere, products of combustion, hygroscopic degassing or fluxing materials, reactive materials in the melt, and hydrated corrosion products on feed material.
The hydrogen formed is absorbed by the liquid aluminium and unless most of it is removed by degassing techniques, porosity will be observed in the casting.
So, an accurate measurement of hydrogen in the melt before casting is essential to ensure that degassing operations achieve the specified quality acceptance value.
This measurement is available on the foundry shop floor, using Hyscan II Hydrogen in Aluminium Analyser, UK manufactured and supported, by MechaTech Systems Ltd.
Hyscan II is a hydrogen analyser that measures hydrogen during aluminum alloy processing operations. It uses a quantitative reduced pressure technique to provide the operator with a quantitative measurement of hydrogen in the melt within five minutes of sampling.
Hyscan II is a robust and designed specifically for use on the shop floor. It is rugged and easy to operate, and it provides accurate results with less than 5% difference between that of the vacuum sub-fusion method.
Hyscan II can be used for a variety of purposes, including quality control, process investigation, and the evaluation of melt treatments.
By monitoring hydrogen levels during the casting process, Hyscan II can help to identify potential problems and prevent defects, leading to lower scrap rates, reduced energy and labour costs, and improved product quality. The financial savings from using Hyscan II can be enough to offset the cost of the instrument within one year.
Hyscan II is a global leader in the measurement of porosity in aluminum castings. Its proven method and accuracy have made it a trusted tool for production foundries around the world.
Read more about Hyscan II Hydrogen in Aluminium Analyser on our website: https://www.mechatechsystems.co.uk/hyscan-analyser
Contact Us for more information: enquiries@mechatechsystems.co.uk / +44 (0) 1454 414723.