{"688132":{"#nid":"688132","#data":{"type":"news","title":"Obstacle or Accelerator? How Imperfections Affect Material Strength","body":[{"value":"\u003Cp dir=\u0022ltr\u0022\u003EImagine a material cracking \u2014 now imagine what happens if there are small inclusions in the material. Do they create an obstacle course for the crack to navigate, slowing it down? Or do they act as weak points, helping the crack spread faster?\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EHistorically, most engineers believed the former, using heterogeneities, or differences, in materials to make materials stronger and more resilient. However, research from Georgia Tech is showing that, in some cases, heterogeneities make materials weaker and can even accelerate cracks.\u0026nbsp;\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003ELed by\u0026nbsp;\u003Ca href=\u0022https:\/\/physics.gatech.edu\/\u0022\u003ESchool of Physics\u003C\/a\u003E Assistant Professor\u0026nbsp;\u003Ca href=\u0022https:\/\/physics.gatech.edu\/user\/itamar-kolvin\u0022\u003E\u003Cstrong\u003EItamar Kolvin\u003C\/strong\u003E\u003C\/a\u003E, the study, \u201c\u003Ca href=\u0022https:\/\/journals.aps.org\/prl\/abstract\/10.1103\/j4vb-y1ng\u0022\u003EDual Role for Heterogeneity in Dynamic Fracture\u003C\/a\u003E,\u201d was published in\u0026nbsp;\u003Cem\u003EPhysical Review Letters\u0026nbsp;\u003C\/em\u003Ethis fall.\u0026nbsp;\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EWhile Kolvin\u2019s work is theoretical, the results of the research are widely applicable. \u201cPredicting this type of toughening effect helps engineers decide how much reinforcement to add to a material, and the best way to do so,\u201d he says. \u201cCracks are complex \u2014 they interact with the material, change shape, and respond dynamically. All of this affects the overall toughness, which impacts safety.\u201d\u003C\/p\u003E\u003Ch3 dir=\u0022ltr\u0022\u003EBuilding Strong Materials\u003C\/h3\u003E\u003Cp dir=\u0022ltr\u0022\u003EThe study found that the key to crack behavior starts at the microscopic level where the material\u2019s microscopic structure influences how it resists cracks running at different speeds.\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003E\u201cCracks propagate by breaking bonds, and that costs energy,\u201d he explains. \u201cOn top of this, materials experience extreme deformations close to where the crack runs, which costs additional energy. In some materials, the amount of this energy cost can depend on the crack\u2019s speed because of microscopic friction between molecules.\u201d\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EOther materials, like window glass, are mostly indifferent to the crack speed. These materials are made of simple molecules, allowing a crack to propagate slowly or quickly using the same amount of energy. The researchers found that including heterogeneities can help strengthen these materials.\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EMaterials made of more complex molecules, like polymer plastics and gels, on the other hand,\u0026nbsp;\u003Cem\u003Eare\u003C\/em\u003E velocity dependent: it takes more energy for a crack to propagate faster. In these materials, heterogeneities are less effective at toughening, and if the crack is fast enough, heterogeneities could help it advance. \u201cThat\u2019s something we didn\u2019t expect when we started,\u201d Kolvin says.\u003C\/p\u003E\u003Ch3 dir=\u0022ltr\u0022\u003EDisorder Versus Design\u003C\/h3\u003E\u003Cp dir=\u0022ltr\u0022\u003EAfter discovering which types of materials can benefit from heterogeneities, Kolvin wanted to investigate the best way to add them. \u201cNatural materials like rocks are usually very messy and disordered,\u201d he explains, \u201cbut in engineering, heterogenous materials tend to be patterned.\u201d For example, imagine a manufactured material: heterogeneities may be added in a grid-like or other patterned way. Now, contrast that with the irregular freckles and inclusions you might see in a rock found in a streambed.\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EKolvin\u2019s question was simple: which material was stronger? The results, again, were surprising. The disordered case \u2014 similar to what is found in nature \u2014 created the toughest material.\u0026nbsp;\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EAmong the patterned materials the team tested, only one was as tough as the disordered case \u2014 and every other pattern tested made the material weaker.\u003C\/p\u003E\u003Ch3 dir=\u0022ltr\u0022\u003EFrom Lab to Landscape\u003C\/h3\u003E\u003Cp dir=\u0022ltr\u0022\u003EAt Georgia Tech, Kolvin\u2019s lab focuses on the mechanics of materials \u2014 both solid and fluid. \u201cWe are using our expertise in physics to explore questions across different fields,\u201d he says. \u201cA common concept is treating materials as continua \u2014 zooming out from molecular detail to look at how materials deform and flow at the large scale.\u201d\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003EThis current research follows suit with applications ranging from investigating the smallest material microstructures to predicting earthquake fractures. \u201cEarthquake faults are highly disordered, and simulating these ruptures is a major challenge, usually requiring supercomputers to solve crack propagation in three dimensions,\u201d Kolvin says. \u201cBut with the tools our study has developed, we can simulate similar conditions and large systems using just a desktop computer.\u201d\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003E\u201cThis opens the doors for scientists, engineers, physicists, and geologists to explore problems right from their own computer, allowing more researchers access to more tools,\u201d he adds. \u201cAnd new tools often lead to new discoveries.\u201d\u003C\/p\u003E\u003Cp dir=\u0022ltr\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EDOI:\u0026nbsp;\u003Ca href=\u0022https:\/\/doi.org\/10.1103\/j4vb-y1ng\u0022\u003Ehttps:\/\/doi.org\/10.1103\/j4vb-y1ng\u003C\/a\u003E\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EResearch from Georgia Tech is showing how cracks occur and spread through materials \u2014 and how best to prevent them.\u0026nbsp;\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Research from Georgia Tech is showing how cracks occur and spread through materials \u2014 and how best to prevent them. "}],"uid":"35599","created_gmt":"2026-02-09 17:14:44","changed_gmt":"2026-02-19 17:33:17","author":"sperrin6","boilerplate_text":"","field_publication":"","field_article_url":"","location":"Atlanta, GA","dateline":{"date":"2026-02-16T00:00:00-05:00","iso_date":"2026-02-16T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"679225":{"id":"679225","type":"image","title":"\u201cCracks are complex \u2014 they interact with the material, change shape, and respond dynamically,\u0022 says Kolvin. \u0022All of this affects the overall toughness, and that impacts safety.\u201d (Adobe Stock)","body":"\u003Cp dir=\u0022ltr\u0022\u003E\u201cCracks are complex \u2014 they interact with the material, change shape, and respond dynamically,\u0022 says Kolvin. \u0022All of this affects the overall toughness, and that impacts safety.\u201d (Adobe Stock)\u003C\/p\u003E","created":"1770657667","gmt_created":"2026-02-09 17:21:07","changed":"1770657667","gmt_changed":"2026-02-09 17:21:07","alt":"A crack in a building wall.","file":{"fid":"263358","name":"AdobeStock_494169649.jpeg","image_path":"\/sites\/default\/files\/2026\/02\/09\/AdobeStock_494169649.jpeg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/2026\/02\/09\/AdobeStock_494169649.jpeg","mime":"image\/jpeg","size":2360933,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/2026\/02\/09\/AdobeStock_494169649.jpeg?itok=Q7lTZSc8"}},"679224":{"id":"679224","type":"image","title":"Itamar Kolvin","body":"\u003Cp\u003EItamar Kolvin\u003C\/p\u003E","created":"1770657296","gmt_created":"2026-02-09 17:14:56","changed":"1770657296","gmt_changed":"2026-02-09 17:14:56","alt":"Itamar Kolvin","file":{"fid":"263357","name":"Itamar-Kolvin.jpeg","image_path":"\/sites\/default\/files\/2026\/02\/09\/Itamar-Kolvin_0.jpeg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/2026\/02\/09\/Itamar-Kolvin_0.jpeg","mime":"image\/jpeg","size":154592,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/2026\/02\/09\/Itamar-Kolvin_0.jpeg?itok=e0T6C0ih"}}},"media_ids":["679225","679224"],"groups":[{"id":"1278","name":"College of Sciences"},{"id":"660369","name":"Matter and Systems"},{"id":"1188","name":"Research Horizons"},{"id":"126011","name":"School of Physics"}],"categories":[{"id":"145","name":"Engineering"},{"id":"150","name":"Physics and Physical Sciences"},{"id":"135","name":"Research"}],"keywords":[{"id":"192249","name":"cos-community"},{"id":"187915","name":"go-researchnews"}],"core_research_areas":[{"id":"39531","name":"Energy and Sustainable Infrastructure"},{"id":"193652","name":"Matter and Systems"}],"news_room_topics":[{"id":"71881","name":"Science and Technology"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EWritten by \u003Ca href=\u0022mailto: sperrin6@gatech.edu\u0022\u003ESelena Langner\u003C\/a\u003E\u003Cbr\u003ECollege of Sciences\u003Cbr\u003EGeorgia Institute of Technology\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}