Laser 'blacksmith' to improve aerospace metal treatment

Researchers at the UK Science and Technology Facilities Council’s (STFC) Central Laser Facility (CLF) have developed a laser tool for treating metals using a concept similar to that of traditional blacksmith’s hammer. The tool will be operated at a newly commissioned laser processing laboratory at the facility, which was designed with the intention of developing unique methods of advance metal surface treatment for high-value manufacturing, for example in high stress machinery such as aerospace components.

A robotic arm is used to manoeuvre the metal samples into path of the laser 'blacksmith' beam. (Image: STFC)

The new tool will be powered by the facility's in-house laser platform DiPOLE (Diode Pumped Optical Laser system for Experiments), and will be capable of treating metals at a much greater precision and speed than traditional methods.

The laser ‘blacksmith’ will be used to deliver powerful nanosecond pulses to a metal target, sending shockwaves into the material that compress the structure’s atoms and leave it locked in a compressed state. This makes the metal much more resilient and resistant to cracks.

The mechanics are similar to that of a blacksmith's hammer being used to shape metal. However, rather than relying on the accuracy of a person, the pulsed laser is instead able to target precise areas of a metal structure. The resulting compressive shockwave can be tailored by adjusting the laser’s parameters.

‘This is the latest application to be developed by the team at CLF where we have used the experience of our laser experts to address potential problems for industry,’ said John Collier, director of CLF. ‘Our next step will be to automate the technology using robotics to enable the treatment of large engineering components – this will save time and reduce costs, making the technique more broadly attractive to industry.’

The laser shock peening technique is of specific importance to high-value sectors including nuclear power generation and aerospace, where aircraft engine fan blades can be laser peened to improve their resistance to bird strikes.

‘At CLF our lasers are among the most powerful in the world and have been used for a wide range of research such as probing the internal structure of matter under extreme conditions,’ said Dr James Nygaard, development laser scientist at CLF. ‘We can harness the power of these laser technologies to solve real-world engineering problems, and through the development of the laser shock peening technique there is potential to revolutionise the way metals for high-stress machinery are manufactured.’