Pure alumina ceramic tube and 95 alumina ceramic （the ceramic with 95.84% alumina） tube were prepared by using self-prepared alumina micrometer powder without agglomeration as raw material. The ceramic green was sha...Pure alumina ceramic tube and 95 alumina ceramic （the ceramic with 95.84% alumina） tube were prepared by using self-prepared alumina micrometer powder without agglomeration as raw material. The ceramic green was shaped by isostatic pressing and sintered at different temperature from 800 to 1 600 ℃ for 2 h. The 95 ceramic tube sintered at 1 550 ℃ for 2 h had mean particle size of 4 μm, bend strength of 437 MPa and volume density of 3.714 g/cm3. Shape memory effect during sintering was observed. XRD results showed that no phase transition occurred during shape memory process, which indicated that shape memory effect was not caused by phase transition. Several probable causes of the alumina ceramic shape memory effect were discussed in this paper.展开更多
In this paper,Si_(3)N_(4) was used as a novel solid-state sintering additive to prepare AION transparent ceramics with high transparency and flexural strength via the pressureless pre-sintering and hot isostatic press...In this paper,Si_(3)N_(4) was used as a novel solid-state sintering additive to prepare AION transparent ceramics with high transparency and flexural strength via the pressureless pre-sintering and hot isostatic pressing(HIP)method at a relatively low HIP temperature(1800℃).The effect of Si_(3)N_(4) content on the phase,microstructure,optical property,and flexural strength was investigated.The experimental results showed that a Si element was homogenously distributed in both pre-sintered and HIPed AION ceramics.The densification enhanced,the grain grew with the increasing Si_(3)N_(4) content in the pre-sintered AION ceramics,and all the samples became pore-free after HIP,which favor transparency.The AION ceramics doped with 0.10 wt%Si_(3)N_(4) had the highest transmittance of 83.8%at 600 nm and 85.6%at 2000 nm(4 mm in thickness),with flexural strength of 404 MPa,which were higher than those of the previous reports.展开更多
基金Funded by the Natural Science Foundation of Guangxi University for Nationalities(Nos.200702YJ19 and 2008ZD011)National Natural Science Foundation of China(No.51172049)+2 种基金Special Prophase Project of 973 Program Research of China(No.2012CB722804)Guangxi Higher Education Institutes Talent Highland Innovation Team Scheme(No.GJR201147-12)Construction Project of Key Laboratory of Chemical and Biological Transformation Process of Guangxi Higher Education Institutes(No.GJKY20129)
文摘Pure alumina ceramic tube and 95 alumina ceramic （the ceramic with 95.84% alumina） tube were prepared by using self-prepared alumina micrometer powder without agglomeration as raw material. The ceramic green was shaped by isostatic pressing and sintered at different temperature from 800 to 1 600 ℃ for 2 h. The 95 ceramic tube sintered at 1 550 ℃ for 2 h had mean particle size of 4 μm, bend strength of 437 MPa and volume density of 3.714 g/cm3. Shape memory effect during sintering was observed. XRD results showed that no phase transition occurred during shape memory process, which indicated that shape memory effect was not caused by phase transition. Several probable causes of the alumina ceramic shape memory effect were discussed in this paper.
基金supported by the Natural Science Foundation of Shanghai(Grant No.19ZR1465000)the National Natural Science Foundation of China(Grant No.51902330).
文摘In this paper,Si_(3)N_(4) was used as a novel solid-state sintering additive to prepare AION transparent ceramics with high transparency and flexural strength via the pressureless pre-sintering and hot isostatic pressing(HIP)method at a relatively low HIP temperature(1800℃).The effect of Si_(3)N_(4) content on the phase,microstructure,optical property,and flexural strength was investigated.The experimental results showed that a Si element was homogenously distributed in both pre-sintered and HIPed AION ceramics.The densification enhanced,the grain grew with the increasing Si_(3)N_(4) content in the pre-sintered AION ceramics,and all the samples became pore-free after HIP,which favor transparency.The AION ceramics doped with 0.10 wt%Si_(3)N_(4) had the highest transmittance of 83.8%at 600 nm and 85.6%at 2000 nm(4 mm in thickness),with flexural strength of 404 MPa,which were higher than those of the previous reports.
