Practical usage and advances in Thermal Analysis

of Cast Irons

Members of the Lancashire Branch, and guests, gathered at PMT Industries recently to hear a presentation from Karl Hopkins of A&S Metallurgical Resources Ltd.

The meeting was hosted by Branch Secretary Ricky Cairns, pictured with Karl, and dedicated to Matt Rutter, who sadly died suddenly last year. Matt was well known and liked both in the branch and the wider industry and was a past branch president.

Karl’s presentation was on ATAS, the adaptive thermal analysis system. The system is able to analyse the cooling curves for grey, ductile and compacted graphite cast irons enabling a footprint cooling curve to be produced for each alloy for a foundry. This footprint can then be used as a tool to help the foundry better to understand their metal as part of an on-going yield improvement and scrap reduction programme and also more immediately to understand and make necessary adjustments to the melt, prior to casting. This can help to minimise the day to day variations in quality that foundries experience even when they feel that inputs are consistent.

The system uses full analysis, including differentiation, of the cooling curves to identify key change points during cooling and, as it does not rely upon chilled iron, results are very detailed and reliable.

Karl explained how foundries can easily be misled by simpler tools which do not fully characterise the metal and do not indicate such measures as inoculation potential, active carbon and trace elements, factors which can affect solidification phases and shrinkage tendencies. ATAS enables a far greater understanding of the metal which can then lead to a far greater level of predictability and hence control.

A&S bought its first ATAS system from Novacast AB in 2001 and now has 3 portable units that its technical experts now use to diagnose and solve casting problems for its customers. It is also an agent for Novacast in the UK, France, Spain and India where increasingly ATAS is being seen as a vital tool, part of the foundry’s armoury, alongside such tools as simulation software, to maximise quality control and minimise inconsistency.

The branch is grateful to A&S Metallurgical Resources Ltd for sponsoring the refreshments and to PMT Industries for hosting the meeting.

The next branch event is the AGM and General Meeting on the 12th April at PMT industries, Bolton. All are welcome to attend.