What happens deep within a metal when we heat or bend it? This question is the focus for the EPFL laboratory of thermomechanical metallurgy, headed by Professor Roland Logé. Since the Chair was founded in 2014, his research team has been working to understand microstructure evolutions in metals. “This helps us make the connection between some of the modifications that occur and the final properties of a material,” explains Professor Logé.
These experiments are linked to the laboratory’s second area of research: additive manufacturing, i.e. the 3D printing of metal alloys. This new technology is shaking up the metal part manufacturing industry, providing an alternative to the long-standing range of casting and machining techniques. In 3D metal printing, thin layers of metallic powder are deposited then recombined using lasers. “We work on different types of alloy, and especially precious metal alloys,” Logé continues.
This manufacturing technique makes it possible to produce parts with incredibly complex geometric configurations. These include hollow forms in which things like sensors can be placed. The technology is beginning to gain ground in industry and big businesses are already investing colossal amounts. As such, the EPFL laboratory is far from alone in conducting this type of research. “We are instead trying to find a niche in which we can become leaders and focus our work on that. One of our main objectives is to optimise the state of stress of materials and to succeed in modifying the microstructure locally, to produce parts with very specific properties. One way of achieving this is by using two very different type of laser.”
The laboratory has some cutting-edge equipment. It employs 18 people, who are either assistants or doctoral students. 50% of the Chair’s funding comes from PX Group. The company is based at La Chaux-de-Fonds and operates in the metals and alloys sector, mainly for the clock-making industry. Roland Logé insists that it is a win-win arrangement. “It is a prime example of great sponsorship. We have total freedom from an academic viewpoint. At the same time, active cooperation with PX Group helps us forge a better understanding of the needs and constraints of the metallurgy industry, which helps us better focus research on aspects that are of value for the local economy.”
Prof. Roland Logé
EPFL, PX Group Chair