Seeking new knowledge of durable cutting surfaces
Surfaces are important. Not least in metal cutting. Mats Boman, Professor of Inorganic Chemistry at Uppsala University’s Ångström Laboratory is leading a major research project that focuses on the surface layer ‘super properties’ that metal-cutting inserts of the future will need. In collaboration with the Royal Institute of Technology, Stockholm (KTH), Chalmers University of Technology, Gothenburg, and Sandvik Group companies Sandvik Coromant and Seco Tools, he is developing new knowledge in the area.
In 2016, Mats and his collaborating partners received more than 30 million SEK from the Swedish Foundation for Strategic Research for the project ‘CVD 2.0 – A new generation of hard coatings’. CVD stands for Chemical Vapour Deposition. In this context, it basically means a method where gaseous substances – source molecules – are converted under pressure and heat in a dedicated reactor to layers that adhere to hard-metal cutting inserts used for industrial machining. These layers, which are very thin, mean that the inserts last longer.
Industry a willing collaborative partner
Being industry-oriented comes naturally to Mats Boman and his idea is that the project may interest industrial companies other than Sandvik, such as SKF and ABB.
“Working with a major industry player is great fun because they are interested in the scientific aspects and possess a sufficiently high level of research innovation”, he says.
Sandvik is an industry leader in metal cutting and participating in research projects with academia is one way for them to stay on top. Engineer Axel Kinell has been in charge of CVD development at Sandvik Coromant since August 2016.
“We can research and develop the performance of our own products, but to explore what will be the high technologies of the future, we need to work with universities”, he notes. “This is about developing ideas and innovations that will bring benefits over many years to come”.
CVD research network very important
With the help of UU Innovation’s Ångström Materials Academy, Swedish CVD workers gathered together during a two-day workshop at the Ångström Laboratory in 2015. A network of university research on CVD was born and Mats Boman could soon initiate collaboration with Sandvik. The company funded two CVD reactors at the department and work got quickly under way.
“That this national initiative came into being was incredibly important. Support from the network already existed and our research was underway when we made the grant application”, says Mats. He adds that the project has already resulted in one patent application for an as yet secret material developed by postgraduate student Linus von Fieandt.
An insert coated with a modern CVD layer has a working life that is hundreds of times longer than an insert without the layer. CVD is thus a way to conserve valuable resources.
“The project also helps to educate very broad-based and knowledgeable postgraduates in the area. They participate in the entire process, from working to discover source molecules to materials analysis. Many of them will ultimately go on to work in industry, and as industry also helps in the teaching process, the overall benefits are felt by many”, comments Mats.
Chain of complementary strengths
With strengths in different parts of the CVD development process, the universities complement each other well. In simple terms, the best experimental ideas emerging from KTH are culled. Professor Gunnar Westin at Uppsala University’s Department of Chemistry then sets about making the new molecules that are to be decomposed for the new hard layers. Thereafter, selected experiments in CVD reactors are performed by Mats Boman or at Sandvik prior to final evaluation at Chalmers. Depending on where in the process the experiments are taking place, the postgrads move between the universities and Sandvik.
What then should the researchers do over the next few years? One important task is to understand exactly how the layers grow at the atomic level. This is done in a synchrotron laboratory, where it is possible to study atomic structures and processes at the microscopic level.
“What happens with the first atomic layers? If we can understand this then hopefully we can influence events in the direction we want”, explains Mats Boman.
Text and photo: Lisa Thorsén