Hailing Yang , Zhi Wang , Mengyong Sun , Fei Chen , Jun Ji , Sique Chen , Yingying Chen , Deli Ma , Zhenyu Zhang , Baocai Pan , Yulin Wei , Qinggang Li
{"title":"pH、研磨时间和异硫胺含量对凝胶铸造多孔氮化硅陶瓷的影响","authors":"Hailing Yang , Zhi Wang , Mengyong Sun , Fei Chen , Jun Ji , Sique Chen , Yingying Chen , Deli Ma , Zhenyu Zhang , Baocai Pan , Yulin Wei , Qinggang Li","doi":"10.1016/j.apmate.2022.100060","DOIUrl":null,"url":null,"abstract":"<div><p>As a non-toxic copolymer of isobutylene and maleic anhydride, Isobam is successfully used as a dispersant and a gelling agent for fabricating porous Si<sub>3</sub>N<sub>4</sub> ceramics by gel casting. The dispersity and rheological properties of the Si<sub>3</sub>N<sub>4</sub> slurry are influenced by the pH, milling time, and Isobam content which varies from 0.1 wt.% to 0.6 wt.%, and these factors are investigated. The slurry with 40 vol.% solid content and milled for 4 h has a high zeta potential at pH 12 (adjusted by Tetramethyl ammonium hydroxide (TMAH)), which means that the particles are well dispersed. The mechanisms of TMAH are electrostatic repulsion and steric hindrance. The viscosity of the slurry increases with the increase of Isobam content. After pressureless sintering at 1700 °C for 2 h, a uniform unique interlocking microstructure of rod-like β-Si<sub>3</sub>N<sub>4</sub> grains is observed, which may improve the flexural strength of the ceramics by intergranular fracture and particle pullout of β-Si<sub>3</sub>N<sub>4</sub> grains. The density and porosity of the samples fluctuate negligibly with the increase of Isobam content, and the Si<sub>3</sub>N<sub>4</sub> ceramic with 0.1 wt.% Isobam exhibits the highest bending strength of 251.6 MPa among all samples.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effect of pH, milling time, and Isobam content on porous silicon nitride ceramics prepared by gel casting\",\"authors\":\"Hailing Yang , Zhi Wang , Mengyong Sun , Fei Chen , Jun Ji , Sique Chen , Yingying Chen , Deli Ma , Zhenyu Zhang , Baocai Pan , Yulin Wei , Qinggang Li\",\"doi\":\"10.1016/j.apmate.2022.100060\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>As a non-toxic copolymer of isobutylene and maleic anhydride, Isobam is successfully used as a dispersant and a gelling agent for fabricating porous Si<sub>3</sub>N<sub>4</sub> ceramics by gel casting. The dispersity and rheological properties of the Si<sub>3</sub>N<sub>4</sub> slurry are influenced by the pH, milling time, and Isobam content which varies from 0.1 wt.% to 0.6 wt.%, and these factors are investigated. The slurry with 40 vol.% solid content and milled for 4 h has a high zeta potential at pH 12 (adjusted by Tetramethyl ammonium hydroxide (TMAH)), which means that the particles are well dispersed. The mechanisms of TMAH are electrostatic repulsion and steric hindrance. The viscosity of the slurry increases with the increase of Isobam content. After pressureless sintering at 1700 °C for 2 h, a uniform unique interlocking microstructure of rod-like β-Si<sub>3</sub>N<sub>4</sub> grains is observed, which may improve the flexural strength of the ceramics by intergranular fracture and particle pullout of β-Si<sub>3</sub>N<sub>4</sub> grains. The density and porosity of the samples fluctuate negligibly with the increase of Isobam content, and the Si<sub>3</sub>N<sub>4</sub> ceramic with 0.1 wt.% Isobam exhibits the highest bending strength of 251.6 MPa among all samples.</p></div>\",\"PeriodicalId\":7283,\"journal\":{\"name\":\"Advanced Powder Materials\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Advanced Powder Materials\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2772834X22000434\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advanced Powder Materials","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2772834X22000434","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Effect of pH, milling time, and Isobam content on porous silicon nitride ceramics prepared by gel casting
As a non-toxic copolymer of isobutylene and maleic anhydride, Isobam is successfully used as a dispersant and a gelling agent for fabricating porous Si3N4 ceramics by gel casting. The dispersity and rheological properties of the Si3N4 slurry are influenced by the pH, milling time, and Isobam content which varies from 0.1 wt.% to 0.6 wt.%, and these factors are investigated. The slurry with 40 vol.% solid content and milled for 4 h has a high zeta potential at pH 12 (adjusted by Tetramethyl ammonium hydroxide (TMAH)), which means that the particles are well dispersed. The mechanisms of TMAH are electrostatic repulsion and steric hindrance. The viscosity of the slurry increases with the increase of Isobam content. After pressureless sintering at 1700 °C for 2 h, a uniform unique interlocking microstructure of rod-like β-Si3N4 grains is observed, which may improve the flexural strength of the ceramics by intergranular fracture and particle pullout of β-Si3N4 grains. The density and porosity of the samples fluctuate negligibly with the increase of Isobam content, and the Si3N4 ceramic with 0.1 wt.% Isobam exhibits the highest bending strength of 251.6 MPa among all samples.