Thixotropic technology to revolutionise diecasting
Instead of ramming molten metals into dies, Australian researchers have developed thixotropic technology in which a semi-solid-feed metal is forced into the dies to reduce porosity.
CSIRO Manufacturing and Infrastructure Technology
Australian researchers who have worked quietly over several years in a long ignored area of metallurgy have been rewarded with a startling discovery, which is set to reshape the way metals are manufactured around the world.
CSIRO's (Commonwealth Scientific and Industrial Research Organisation) Advanced Thixotropic Metallurgy (ATM) casting technology is now in the final proving-out stage and the results herald a new age of quality high-pressure die-casting (HPDC).
ATM is particularly suited to aluminium or magnesium alloys and offers consumers lower costs and improved quality across a wide range of product applications from safety critical automotive components to cases for mobile phones, laptops and cameras.
Traditional high-pressure die-casting (HPDC) involves molten metal being rammed into a casting through small tunnels called runners, which traditionally have overflows zones or over-flow spaces on the exit side of the die to reduce/improve internal porosity.
Barrie Finnin of CSIRO Elaborately Transformed Metals says, 'CSIRO's approach is a radical rethink of high pressure die-casting runner design. It moves in completely the opposite direction to recent die-casting technology based on larger runner apertures and hotter castings designed to reduce porosity - the enemy of the die-caster.' Finnin says, 'ATM is a system that, linked to the principle of a semi-solid-feed (cooler molten metal) and narrower runners with reduced overflows, reduces the cost of manufacturing castings 'ATM,' he says, 'essentially covers off on the die-casters wish list - reduced reject rates, reduced cycle (production) time lowering labour and machine costs with a system that can be applied to most existing machines and using stock feed materials.' Finnin says, 'The overall effect of ATM is an exceptionally low porosity casting, with very low wastage'.
Advanced Thixotropic Metallurgy (ATM) casting technology is a CSIRO patented breakthrough technology.
'The technology has been branded 'the new Australian runner system.' Finnin says, 'The commercial impact of CSIRO's ATM technology will be greater thanks to the development of CSIRO design software tools which enable a dramatic reduction in cost and time-to-market'.
Early applications of the technology were hampered by the need for computer modelling and simulation, which is expensive and time consuming, involving special skills to simulate complex shapes and to analyse data produced.
'In a complete turnaround', Finnin says, 'We were able to design an ATM runner system for an automotive aluminium alloy (ADC12) extension housing, and conduct the trial at Nissan Casting Australia, all in one day.' Nissans' R and D Co-ordinator, Jenny Law has called the trial, 'The 'wonder-trial' and says, 'The parts passed Nissan production quality standards with X-ray results showing they were equivalent and in some cases better than the conventional HPDC castings.' Other benefits offered by the CSIRO ATM include:
- reduced projected area, resulting in the possibility of a smaller machine than conventional HPDC or more die cavities per casting.
- shorter cycle time improving plant productivity.
- finer microstructure (associated with improved strength).
- redesign of components for thinner sections, offering weight/cost reductions.
- expanded design limits for components beyond the capability of HPDC.
- increased energy efficiency.
CSIRO ATM Team belongs to CSIRO Elaborately Transformed Metals, a team of 80 engineers, scientists and technicians with a high international standing in research and development focussing on light alloys, casting, joining, tooling and advanced metals processing.
The group has considerable expertise with aluminium, magnesium and titanium.
CSIRO ATM is protected by a number of international patents.
Licenses and support for CSIRO ATM is available within Australia now, and CSIRO is talking to a number of selected offshore manufacturers interested in technology licenses.
A small but growing number of license agreements have been finalised with licensees in North America and Europe.
Have your say...
The approval of your comment is at the discretion of this article's publisher. Write your comment with the following in mind to ensure the highest likelihood of it being approved:
- No promotional undertones
- No use of profanity
- Good spelling, grammar and layout
- Check punctuation, language and missing words
- No use of aggression
- No unsubstantiated claims
We reserve the right to remove comments at our discretion.
Your name is used alongside Comments.