粉末冶金材料科学与工程
粉末冶金材料科學與工程
분말야금재료과학여공정
POWDER METALLURGY MATERIALS SCIENCE AND ENGINEERING
2013年
3期
429-433
,共5页
镁稳定氧化锆%溶胶-凝胶法%晶粒尺寸%四方相
鎂穩定氧化鋯%溶膠-凝膠法%晶粒呎吋%四方相
미은정양화고%용효-응효법%정립척촌%사방상
magnesium stabilized zirconia%sol-gel%grain size%tetragonal phase
以草酸为络合剂,采用溶胶–凝胶法制备一系列氧化镁稳定氧化锆粉末 Zr1?xMgxO2?x(0.04≤x≤0.10),利用 X 射线衍射(XRD)、场发射扫描电镜(FESEM)等分析技术对粉末进行表征。结果表明,掺杂氧化镁后,低温350~450℃煅烧产物晶型为四方相(t-ZrO2),随煅烧温度升高,t-ZrO2逐渐向 m-ZrO2转变。在550℃下煅烧时,少部分四方相转变为单斜相(m-ZrO2),转变比例随掺杂量增加而降低。Mg2+取代 Zr4+产生氧缺陷是 ZrO2晶体结构稳定的主要因素。随煅烧温度从350℃升高到650℃,Zr0.92Mg0.08O1.92粉末中 t-ZrO2晶粒尺寸从42 nm 长大到100 nm;随 Mg 掺杂量从0.04增加到0.10,t-ZrO2晶粒尺寸从110 nm 减小到97.8 nm,而纳米尺寸晶粒有利于 t-ZrO2稳定。
以草痠為絡閤劑,採用溶膠–凝膠法製備一繫列氧化鎂穩定氧化鋯粉末 Zr1?xMgxO2?x(0.04≤x≤0.10),利用 X 射線衍射(XRD)、場髮射掃描電鏡(FESEM)等分析技術對粉末進行錶徵。結果錶明,摻雜氧化鎂後,低溫350~450℃煅燒產物晶型為四方相(t-ZrO2),隨煅燒溫度升高,t-ZrO2逐漸嚮 m-ZrO2轉變。在550℃下煅燒時,少部分四方相轉變為單斜相(m-ZrO2),轉變比例隨摻雜量增加而降低。Mg2+取代 Zr4+產生氧缺陷是 ZrO2晶體結構穩定的主要因素。隨煅燒溫度從350℃升高到650℃,Zr0.92Mg0.08O1.92粉末中 t-ZrO2晶粒呎吋從42 nm 長大到100 nm;隨 Mg 摻雜量從0.04增加到0.10,t-ZrO2晶粒呎吋從110 nm 減小到97.8 nm,而納米呎吋晶粒有利于 t-ZrO2穩定。
이초산위락합제,채용용효–응효법제비일계렬양화미은정양화고분말 Zr1?xMgxO2?x(0.04≤x≤0.10),이용 X 사선연사(XRD)、장발사소묘전경(FESEM)등분석기술대분말진행표정。결과표명,참잡양화미후,저온350~450℃단소산물정형위사방상(t-ZrO2),수단소온도승고,t-ZrO2축점향 m-ZrO2전변。재550℃하단소시,소부분사방상전변위단사상(m-ZrO2),전변비례수참잡량증가이강저。Mg2+취대 Zr4+산생양결함시 ZrO2정체결구은정적주요인소。수단소온도종350℃승고도650℃,Zr0.92Mg0.08O1.92분말중 t-ZrO2정립척촌종42 nm 장대도100 nm;수 Mg 참잡량종0.04증가도0.10,t-ZrO2정립척촌종110 nm 감소도97.8 nm,이납미척촌정립유리우 t-ZrO2은정。
Nano-powder magnesia stabilized zirconia Zr1?xMgxO2?x powders were prepared by sol-gel process using oxalic acid as precipitant. The crystal phase composition and structure of oxide powders were determined by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM), respectively. The results of XRD show that tetragonal phase ZrO2 and little monoclinic phase ZrO2 form at 550 ℃, while the tetragonal Zr1?xMgxO2?x forms at 350 ℃. When x is below 0.08 and with temperature increasing, part of t-ZrO2 transforms to m-ZrO2 , and the ratio of transformtion decreases with increasing x value, when x is above 0.10, t-ZrO2 transformation ratio increases with increasing temperature. The generation of oxygen defect after Mg2+ replacing Zr4+ is the main factor to influence the stabilization of the ZrO2 crystal structure. The crystillize size of t-ZrO2 increases from 42 nm to 100 nm when temperature increases from 350 ℃ to 650 ℃, and t-ZrO2 crystillize size decreases from 110 nm to 97.8 nm with MgO-doped amount increases from 0.04 to 0.10. Nano grain size is favorable for the stability of t-ZrO2.