利用铝热还原金属铬炉渣制备彩色氧化锆陶瓷

为提升氧化锆陶瓷的使用性能,采用氧化钇稳定的四方氧化锆为基体（yttria stabilized tetragonal zirconia,3Y-TZP）,将铝热法生产金属铬所得炉渣（铝铬渣）按照不同比例（质量分数为5%~15%）加入,利用无压烧结在1 400 ℃保温2 h制备出彩色氧化锆陶瓷。通过X射线衍射（XRD）、扫描电镜（SEM）、显微硬度计及万能材料试验机测试了试样的物相、显微结构及力学性能。结果表明：掺杂铝铬渣可以制备出粉红色系氧化锆复合陶瓷,其物相主要为四方氧化锆、单斜氧化锆和含铬的氧化铝,并且铝铬渣的加入促使更多的四方氧化锆保留到室温。铝铬渣的加入不利于试样的烧结致密性,随着其含量增加复合陶瓷烧结后的体积收缩率降低,基体内出现部分孔隙。但是,铝铬渣的加入提升了试样的力学性能,当其加入量为5%（质量分数）时,氧化锆复合陶瓷的显微硬度和抗折强度均达到最大值,分别为1 755.3 HV和421.3 MPa。

Preparation of colored zirconia ceramics by adding alumina-chrome slag from aluminothermic reduction

Colored zirconia ceramics were prepared by pressureless sintering at 1400℃for 2 h with yttrium stabilized zirconia(3 Y-TZP)as substrate and slag from aluminothermic reduction(alumina-chrome slag,mass fraction of 5%~15%)as additive in order to improve the performance of ZrO₂ceramics.The phase,microstructure and mechanical properties of samples were characterized by XRD,SEM,microhardness tester and universal material testing machine,respectively.It is demonstrated that the pink ZrO₂composite ceramics can be prepared with alumina-chrome slag additive,which consists of tetragonal ZrO₂,monoclinal ZrO₂and(Cr-doped)-Al2 O3.Moreover,the addition of alumina-chrome slag promotes more tetragonal ZrO₂to be retained at room temperature.The addition of alumina-chrome slag hindered the sintering compactness of samples.The sintering volume shrinkage rate of ZrO₂composite ceramics was decreased by increasing the content of aluminachrome slag and pores were observed in the substrate.However,the mechanical properties of composite ceramics was improved by addition of aluminachrome slag.When the content of alumina-chrome slag was 5%,the microhardness and flexural strength of ZrO₂ceramics reached the maximum value of 1755.3 HV and 421.3 MPa,respectively.