{"id":785,"date":"2025-08-22T15:20:44","date_gmt":"2025-08-22T07:20:44","guid":{"rendered":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/?post_type=paper&#038;p=785"},"modified":"2025-08-22T15:20:45","modified_gmt":"2025-08-22T07:20:45","slug":"preparation-of-high-hardness-and-high-fracture-toughness-si3n4-ceramics-by-combining-in-situ-nitriding-and-hot-press-sintering","status":"publish","type":"paper","link":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/paper\/preparation-of-high-hardness-and-high-fracture-toughness-si3n4-ceramics-by-combining-in-situ-nitriding-and-hot-press-sintering\/","title":{"rendered":"Preparation of high hardness and high fracture toughness Si3N4\u00a0ceramics by combining in-situ nitriding and hot-press sintering"},"content":{"rendered":"\n<p><strong>Author:<\/strong>\u00a0Shiao\u00a0Wu\u00a0<sup>ab1<\/sup>,\u00a0Yang\u00a0Li\u00a0<sup>b1<\/sup>,\u00a0Yueming\u00a0Li\u00a0<sup>c<\/sup>,\u00a0Fuyuan\u00a0Zheng\u00a0<sup>b<\/sup>,\u00a0Zhongyi\u00a0Zhao\u00a0<sup>a<\/sup>,\u00a0Xiangqing\u00a0Kong\u00a0<sup>d<\/sup>,\u00a0Guorui\u00a0Zhao\u00a0<sup>b<\/sup><\/p>\n\n\n\n<p><strong>Journal<\/strong>: <a href=\"https:\/\/www.sciencedirect.com\/journal\/vacuum\">Vacuum<\/a><\/p>\n\n\n\n<p><strong>DOI:<\/strong>\u00a0<a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.1016\/j.vacuum.2025.114402\" target=\"_blank\">https:\/\/doi.org\/10.1016\/j.vacuum.2025.114402<\/a><a rel=\"noreferrer noopener\" href=\"https:\/\/s100.copyright.com\/AppDispatchServlet?publisherName=ELS&amp;contentID=S0042207X25003926&amp;orderBeanReset=true\" target=\"_blank\">Get rights and content<\/a><\/p>\n\n\n\n<p><strong>Abstract \/&nbsp;\u6458\u8981<\/strong><\/p>\n\n\n\n<p>Preparation Si<sub>3<\/sub>N<sub>4<\/sub>&nbsp;ceramics with high hardness and high fracture toughness is a challenge. In this work, Si<sub>3<\/sub>N<sub>4<\/sub>&nbsp;ceramics with high hardness (18.35&nbsp;\u00b1&nbsp;0.40&nbsp;GPa) and high fracture toughness (8.54&nbsp;\u00b1&nbsp;0.26&nbsp;MPa&nbsp;m<sup>1\/2<\/sup>) were obtained by in-situ nitriding of Si and Y powders and hot-press sintering. By controlling Y content, Si<sub>3<\/sub>N<sub>4<\/sub>&nbsp;powders with different \u03b1-Si<sub>3<\/sub>N<sub>4<\/sub>&nbsp;ratios were obtained, which in turn regulated grain size and morphology of Si<sub>3<\/sub>N<sub>4<\/sub>&nbsp;ceramics after sintering. Addition of Y introduces Y-Si-O-N crystalline phase into nitrided powder, which transitions to Y<sub>2<\/sub>Si<sub>2<\/sub>O<sub>7<\/sub>&nbsp;during subsequent sintering. Y<sub>2<\/sub>Si<sub>2<\/sub>O<sub>7<\/sub>&nbsp;phase reduces bulk hardness but introduces residual stresses at interface, promotes grain elongation, and improves fracture toughness through crack bridging, stretching, and crack deflection mechanisms. In addition, atomic-scale&nbsp;<a href=\"https:\/\/www.sciencedirect.com\/topics\/materials-science\/microstructural-analysis\">microstructural analysis<\/a>&nbsp;reveals coherent interfaces were formed between both Si<sub>3<\/sub>N<sub>4<\/sub>\/SiO<sub>2<\/sub>\/Y<sub>2<\/sub>Si<sub>2<\/sub>O<sub>7<\/sub>&nbsp;as well as Si<sub>3<\/sub>N<sub>4<\/sub>\/Si<sub>2<\/sub>N<sub>2<\/sub>O, with crystallographic orientation relationships of (100) Si<sub>3<\/sub>N<sub>4<\/sub>\/\/(100) SiO<sub>2<\/sub>\/\/(\u2212111) Y<sub>2<\/sub>Si<sub>2<\/sub>O<sub>7<\/sub>&nbsp;and [010] Si<sub>3<\/sub>N<sub>4<\/sub>\/\/[001] SiO<sub>2<\/sub>\/\/[12\u20131] Y<sub>2<\/sub>Si<sub>2<\/sub>O<sub>7<\/sub>&nbsp;as well as (100) Si<sub>3<\/sub>N<sub>4<\/sub>\/\/(020) Si<sub>2<\/sub>N<sub>2<\/sub>O and [010] Si<sub>3<\/sub>N<sub>4<\/sub>\/\/[\u2212102] Si<sub>2<\/sub>N<sub>2<\/sub>O. These in-situ generated coherent interfaces significantly enhance mechanical properties and reliability of samples, ensuring both high hardness and high fracture toughness.<\/p>\n\n\n\n<p><strong>Keywords \/\u00a0\u5173\u952e\u8bcd<\/strong><\/p>\n\n\n\n<p>Si<sub>3<\/sub>N<sub>4<\/sub>; Nitridation process; Hot-press sintering; Mechanical properties<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" loading=\"lazy\" width=\"535\" height=\"445\" src=\"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-content\/uploads\/sites\/20\/2025\/08\/1-s2.0-S0042207X25003926-gr8.jpg\" alt=\"\" class=\"wp-image-786\" srcset=\"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-content\/uploads\/sites\/20\/2025\/08\/1-s2.0-S0042207X25003926-gr8.jpg 535w, https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-content\/uploads\/sites\/20\/2025\/08\/1-s2.0-S0042207X25003926-gr8-300x250.jpg 300w\" sizes=\"(max-width: 535px) 100vw, 535px\" \/><\/figure><\/div>","protected":false},"featured_media":787,"template":"","acf":[],"_links":{"self":[{"href":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-json\/wp\/v2\/paper\/785"}],"collection":[{"href":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-json\/wp\/v2\/paper"}],"about":[{"href":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-json\/wp\/v2\/types\/paper"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-json\/wp\/v2\/media\/787"}],"wp:attachment":[{"href":"https:\/\/frontbasic.sslab.org.cn\/ceramics\/wp-json\/wp\/v2\/media?parent=785"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}