Artificial teeth are attached to the jaw with titanium screws. “But often the implant doesn't embed well in the bone tissue,” explains Lukas Kluy, PhD student at the Institute for Production Engineering and Forming Machines at TU Darmstadt. In about eight percent of patients, the insertion actually lasts less than ten years. In the IdentiTi project, Kluy and his colleagues want to solve the problem with a nanostructured titanium alloy. It has a fine-grained surface, which the body's bone cells are better able to adhere to.

The TU engineers produce the new screw material in a special process from a coarse-grained titanium alloy. The starting material is distorted in a machine at 300 degrees Celsius so that the internal structure breaks up and a new fine structure forms. “But the process requires a lot of energy,” says Kluy. Which is already evident from the machine's thick power cables.

In Germany alone, over one million dental implants are fitted every year. If they were all to be made from the nanostructured material, the additional energy requirement would be considerable. Together with Andreas Wächter, who at the time was still a mechanical engineering student looking for a subject for his master's thesis, Kluy wanted to make the production of the nano-alloy more energy efficient.

A process is usually energetically optimised once the individual steps have been determined. Then, for instance, waste heat is used here or there, a component insulated or the control technology optimised. But Wächter had a better idea: “Our process was still being developed, so then you can incorporate energy efficiency right from the start.” In the initial phase there is still a tremendous amount of design freedom, he explains, and measures to save energy can be implemented relatively easily and cost effectively.

In this case, for instance, heating the alloy requires a tremendous amount of energy. “Simply by shortening the form in which the material is heated, we were able to halve the heating time,” explains Wächter. Overall, this reduced the energy consumption by twelve percent.

Kluy and Wächter developed a computer model that digitally maps the value chain. The model simulated the energy efficiency of the entire process. Best of all, it can be transferred to other production processes. A colleague at the institute is currently using the model to optimise a process of roll forming. The technology bends metal strips, for instance in vehicle construction or in the production of window frames.

Last year, their methodology won Wächter and Kluy second prize of the Hessian State Prize for innovative energy solutions. Since they want their idea to spread quickly, they are currently considering an open-access release of their model. Kluy emphasises: “The social benefits are far more important to us than making money from it.” The model is ready for use, and he adds, “Anyone who is interested in it is welcome to get in touch.”