"Stable cutting" technique could slash time taken to produce aerospace components

Researchers at the Advanced Manufacturing Research Centre (AMRC) in Sheffield, UK, have devised a "harmonised stable cutting" technique they believe could significantly reduce the time taken to machine metallic aerospace parts.

AMRC is a joint venture set up by Boeing, Hamble, Technicut and the University of Sheffield, to research machining processes for titanium, inconel and other materials. Launched earlier this year to study the advantages of various cutting tool types, the centre is now researching vibration prevention systems that could reduce "surfacing time" by a factor of between three and 18.

The technique relies on determining stable combinations of cutter spindle speeds and depths, tailored for the component being machined. Prof Keith Ridgway of AMRC says that traditionally machine shops tend to reduce cutting speed if they encounter vibrations, but the AMRC's research suggests that this is an inefficient response. "By identifying 'stable pockets' in spindle speed versus cutting depth plots we can avoid the need to reduce speed. We're now at the stage where the cutting ability is limited only by the machine torque and tool limits, not by vibration," he says.

Separately, AMRC is investigating damping components during machining using simple stick-on powder capsules. "The size of the grains can be adjusted to tailor the damping characteristics," says Ridgway, suggesting that the stick-on technology could form the basis of a spin-off company.

The AMRC's budget is about $25 million over four years, including £5.9 million ($9.8 million) provided by the UK Department of Trade and Industry. The 25-person centre will move to a new 1,400m2 (15,000ft2) building next year, and hopes to double its size as projects gather pace. Ridgway says the centre's work will in the future expand into composites, with current projects including the development of textile-based composite manufacturing technology, composite drill design and laser drilling techniques. Other partner companies working with AMRC include Alcoa, Messier- Dowty, Parametric Technologies and Sandvik.

Source: Flight International