利用传统电炉低温烧结致密Si_(3)N_(4)陶瓷  

Dense Si_(3)N_(4) Ceramics Sintered at Low Temperature in Traditional Electric Furnace

作　　者：李凌锋 赵世贤[1] 郭昂 司瑶晨 王战民[1] 王刚[1] LI Lingfeng;ZHAO Shixian;GUO Ang;SI Yaochen;WANG Zhanmin;WANG Gang(State Key Laboratory of Advanced Refractories,Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.,Luoyang 471039,Henan,China)

机构地区：[1]中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点实验室,河南洛阳471039

出　　处：《材料导报》2022年第4期67-72,共6页Materials Reports

基　　金：国家重点研发计划(2017YFB0310300)。

摘　　要：Si_(3)N_(4)陶瓷具有高硬度、高耐磨以及高抗弯强度等优异特性,常常被应用于冶金、化工以及航空航天等现代化领域。Si_(3)N_(4)的强共价键使其难以致密化,因此热压烧结和气压烧结是目前制备致密Si_(3)N_(4)陶瓷最常见的方法。然而极高的烧结温度以及较大的N_(2)压力需求等极其苛刻的制备条件限制了致密Si_(3)N_(4)陶瓷的基础探索研究和工业化生产应用。因此,本工作提出设计以传统空气电炉作为烧结装置,通过埋碳低温制备致密Si_(3)N_(4)陶瓷,研究该工艺条件下实验用坩埚、填埋Si_(3)N_(4)粉体以及烧结试样的物相变化和微观结构,结果表明:(1)Si_(3)N_(4)的分解使得坩埚表层生成不规则的SiC纤维堆积,较低的氧分压使所埋Si_(3)N_(4)粉体经烧结后仍存在较多Si_(3)N_(4)和少量Si_(2)N_(2)O;(2)烧结后的试样仅表面存在少量Si_(2)N_(2)O,而试样内部并未出现Si_(2)N_(2)O相;(3)1650℃低温烧结后试样致密度达到98%以上,显微组织均匀,且具有良好的性能。Due to its high hardness,high wear resistance and high bending strength,Si_(3)N_(4)ceramic is widely used in metallurgy,chemical industry,ae-rospace and automotive engines.Hot-pressed sintering and gas pressure sintering are commonly used in the preparation of dense Si_(3)N_(4)ceramics due to the high strength bonding of Si_(3)N_(4)which is difficult to be compacted.However,the strict preparation conditions such as high temperature pressure sintering greatly limit the basic research and the industrial application of dense Si_(3)N_(4)ceramics in many technical fields.Therefore,the preparation of dense Si_(3)N_(4)ceramics were obtained at lower sintering temperature using traditional air furnace to study the phase changes and microstructures of experimental crucible,Si_(3)N_(4)powder and sintered sample under the present conditions.The results showed that the decomposition of the Si_(3)N_(4)caused irregular SiC fiber accumulation on the crucible surface,and much more Si_(3)N_(4)and a small amount of Si_(2)N_(2)O phase were remained in the buried Si_(3)N_(4)powder because of the lower oxygen partial pressure.Si_(2)N_(2)O phase were also detected on the surface,but no Si_(2)N_(2)O appeared inside the sintered body.The Si_(3)N_(4)ceramics sintered at 1650℃have the relative density over 98%with uniform microtissue and good performance.

关 键 词：Si_(3)N_(4)陶瓷 低温无压烧结 致密化 相变化 性能 

分 类 号：TQ174[化学工程—陶瓷工业]