新型炭材料（中英文）2025，Vol.40Issue(3)：703-716,14.DOI:10.1016/S1872-5805(25)60995-4
两步烧结法原位引入孔隙增强石墨材料的断裂应变
Improving the fracture strain of graphite materials by in-situ porosity introduction by two-step sintering
摘要
Abstract
High-performance graphite materials have import-ant roles in aerospace and nuclear reactor technologies be-cause of their outstanding chemical stability and high-temper-ature performance.Their traditional production method relies on repeated impregnation-carbonization and graphitization,and is plagued by lengthy preparation cycles and high energy consumption.Phase transition-assisted self-pressurized self-sintering technology can rapidly produce high-strength graph-ite materials,but the fracture strain of the graphite materials produced is poor.To solve this problem,this study used a two-step sintering method to uniformly introduce micro-nano pores into natural graphite-based bulk graphite,achieving im-proved fracture strain of the samples without reducing their density and mechanical properties.Using natural graphite powder,micron-diamond,and nano-diamond as raw materials,and by precisely controlling the staged pressure release process,the degree of diamond phase transition expansion was effectively regulated.The strain-to-failure of the graphite samples reached 1.2%,a 35%increase compared to samples produced by full-pressure sintering.Meanwhile,their flexural strength exceeded 110 MPa,and their density was over 1.9 g/cm3.The process therefore produced both a high strength and a high fracture strain.The interface evolution and toughening mechanism during the two-step sintering process were investigated.It is believed that the micro-nano pores formed have two roles:as stress con-centrators they induce yielding by shear and as multi-crack propagation paths they significantly lengthen the crack propagation path.The two-step sintering phase transition strategy introduces pores and provides a new approach for increasing the fracture strain of brittle materials.关键词
高性能石墨/相变调控/两步烧结法/断裂应变/原位Key words
High-performance graphite/Phase transition control/Two-step sintering process/Fracture strain/In-situ分类
化学化工引用本文复制引用
顾士甲,陈瀚林,王君卓,陆晓芳,王连军,江莞..两步烧结法原位引入孔隙增强石墨材料的断裂应变[J].新型炭材料（中英文）,2025,40(3):703-716,14.基金项目
This work was supported by Natural Science Foundation of Shanghai(24ZR1400800),the Natural Science Foundation of China(U23A20685,52073058,91963204),the National Key R&D Pro-gram of China(2021YFB3701400)and Shanghai Sailing Program(23YF1400200). 上海市自然科学基金(24ZR1400800) （24ZR1400800）
国家自然科学基金(U23A20685,52073058,91963204) （U23A20685,52073058,91963204）
国家重点研发计划(2021YFB3701400) （2021YFB3701400）
上海市启明星扬帆专项(23YF1400200). （23YF1400200）
