Wear-resistant coatings of metal parts deliver improved strength Friday, 09 December 2016

Teams in Russia have developed a way to apply wear-resistant coatings on metals, followed by fusing them in the substrate. These modified metals are light, strong and corrosion resistant, and can be used in mechanical engineering, aviation and space engineering.

The researchers from Tomsk Polytechnic University (TPU) and the Institute of High Current Electronics, created the modified materials from a base of aluminium and silumin, which is an alloy of aluminium and silicon.

According to Maria Rygina, a graduate student from the TPU Department of Nanomaterials and Nanotechnologies, the metals have low weight and good corrosion resistance.

“To use them in air and space engineering we only need to modify their strength and tribological properties: to improve hardness and wear resistance,” she explained.On the aluminium and silumin base, the researchers coated titanium, titanium nitride, and silumin containing 25 per cent silicon.

According to the researchers, the new development with this type of coating is that it is not deposited on the substrate, but rather fused into it using an intense pulsed electron beam. Experiments indicate that this method of coating results in an almost six-fold improvement in the hardness of metal, and three times the wear resistance.

TPU Department of Nanomaterials and Nanotechnologies Yuri Ivanov says fusing coating addresses the main challenge of coatings, which is the adhesion between coating and substrate.

“If coating is simply deposited, then it can be easily removed,” he explained. “Research teams are looking for a solution to this issue by forming multi-layer coating. However, multi-layer deposition takes a long time.

”In contrast, fusing coating requires only microseconds, with significant improvements in adhesion. Key to the ability to carry out fusing coating were the specific electron-ion-plasma installations created by the team from the partnering research institutes. These unique installations were supplied by Japan, China and Canada.

"The metals modified with this new coating technology can be used for manufacturing internal mechanisms’ parts in spacecraft, where they are subject to the most wear. The method can also be used in the production of woodworking tools and components for mechanical engineering."