In reality, contact between solid bodies never occurs over perfectly flat surfaces but through countless microscopic asperities. At these points, stresses can reach tens of gigapascals, leading to local deformation and catastrophic failure. This is particularly critical for protective coatings on cutting tools, turbine blades, and biomedical implants, where contact loads are compounded by high temperatures and aggressive environments.<\/p>\n
Until now, researchers could measure stresses either in the coating or in the indenter, but never simultaneously. Traditional methods only provided averaged pictures with resolutions of tens of microns, while computer simulations relied on assumptions that experiments didn\u2019t always confirm. To overcome this barrier, the team developed a unique nanomechanical probe: a singlecrystal diamond indenter coated with a 3.8micron layer of nanocrystalline diamond. This allowed them to simultaneously record diffraction signals from both the indenter and the coating. By scanning the contact area with an 80nm step, they obtained stress distribution maps with unprecedented detail.<\/p>\n
In the singlelayer coating, compressive stresses under the indenter reached \u201313.4 GPa, and tensile stresses appeared at the interface with the silicon substrate, triggering cracks. In the multilayer coating, the picture was fundamentally different: stresses remained compressive throughout the entire thickness, peak values were reduced, and tensile stresses at the substrate virtually disappeared. Moreover, the zone of intense deformation was broader \u2014 the load was distributed over a larger volume. The key mechanism is that the amorphous ZrCu interlayers, being less rigid and capable of plastic deformation, shield the transmission of stresses between the ZrN layers. This works much like the soft organic layer between mineral plates in nacre, which prevents crack propagation. As a result, the multilayer coating stored only 69% of the elastic energy compared to the singlelayer version \u2014 the remaining 30% was dissipated through plastic deformation of the interfaces.<\/p>\n These findings give engineers solid numerical benchmarks for designing protective coatings of the next generation. For cutting tools, this could increase service life by two to three times by suppressing crack initiation; for gas turbine blades, it could enhance durability under hightemperature oxidation and thermal cycling; and for biomedical implants, it could reduce wear and fretting damage. In addition, the technique developed here is set to become a reference tool for validating computer models of contact mechanics, accelerating the development of new materials.<\/p>\n \u201cImagine trying to understand how pressure is distributed at the contact point between two solid bodies,\u201d commented coauthor Professor Alexander Korsunsky from the Skoltech Engineering Center, the head of the Laboratory for Hierarchically Structured Materials. \u201cPreviously, we could only measure what was happening inside either one body or the other \u2014 but never both at once, and with much poorer resolution. Now, using the latest advances in synchrotron methods, we\u2019ve shown that ultrathin metallic films in multilayer coatings redistribute and dissipate stored elastic energy, acting like damping interlayers. This isn\u2019t just a breakthrough in resolution \u2014 we\u2019re giving engineers a way to directly measure stresses at the level of individual asperities in real contacts, providing a toolkit that Boussinesq, Hertz, and even Greenwood and Williamson could only have dreamed of.\u201d<\/p>\n *****<\/p>\n Skoltech is a private international university (part of the VEB.RF group) in Russia, cultivating a new generation of leaders in technology, science, and business. As a factory of technologies, it conducts research in breakthrough fields and promotes technological innovation to solve critical problems that face Russia and the world. Skoltech focuses on six priority areas: life sciences, health, and agro; telecommunications, photonics, and quantum technologies; artificial intelligence; advanced materials and engineering; energy efficiency and the energy transition; and advanced studies. Established in 2011 in collaboration with the Massachusetts Institute of Technology (MIT), Skoltech was listed among the world\u2019s top 100 young universities by the Nature Index in its both editions (2019, 2021). On Research.com, the Institute ranks as Russian university No. 2 overall and No. 1 for genetics. In the recent SCImago Institutions Rankings, Skoltech placed first nationwide for computer science. Website: https:\/\/www.skoltech.ru\/<\/a>.<\/p>\n \nContent Sourced from scoop.co.nz<\/a>![](\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/08\/eLECIVraBb71zfmF.jpg\")
The probe consists of a singlecrystal diamond tip coated with nanocrystalline diamond via chemical vapour deposition. It was placed in contact with a thin multilayer ZrNZrCu film under constant load, while a 75nm Xray beam scanned a region of interest measuring 20 \u00b5m by 12 \u00b5m. At each loading step, 37,500 twodimensional DebyeScherrer diffractograms were recorded. Image source: How interfaces limit nanoscale stress concentrations and prevent catastrophic failure in single-asperity contacts<\/a> (https:\/\/www.nature.com\/articles\/s43246-026-01239-1) (Photo\/Supplied)<\/p>\n
Original url<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Press Release \u2013 Skoltech These findings give engineers solid numerical benchmarks for designing protective coatings of the next…\n","protected":false},"author":2,"featured_media":143981,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[111,139,69,147],"class_list":["post-568217","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-new-zealand","tag-newzealand","tag-nz","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/568217","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=568217"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/568217\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/143981"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=568217"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=568217"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=568217"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}