摘要
基于多元晶粒生长抑制效应,利用热压烧结方法制备了细晶高致密的Al2O3-TiC复相陶瓷。研究发现,仅利用第二相TiC的晶界钉扎效应,即使其含量高达30wt%,也不能有效地抑制Al2O3基体的晶粒生长。在TiC作为第二相的基础上,引入微量MgO和Y2O3,通过TiC晶界钉扎、MgO溶质滞阻和Y2O3晶界偏析等多元晶粒生长抑制作用,Al2O3基体晶粒尺寸从5.12μm显著减小到1.82μm,Al2O3-TiC复相陶瓷的断裂韧性从3.99±0.18 MPa·m1/2提高到5.24±0.22 MPa·m1/2。研究结果表明:利用多元晶粒生长抑制效应的协同作用,可显著细化Al2O3基复相陶瓷的显微结构,改善其力学性能。
Using the synergetic effects of multiple grain growth inhibition,Al2O3-TiC ceramics with high density and fine grain were fabricated by hot pressing method.It was found that TiC as the second phase was not effective at pinning grain growth of Al2O3 even if the TiC content was 30wt%.On the basis of TiC as a second phase,the introduction of trace amount of MgO and Y2O3 generated synergetic effects of grain growth inhibition mechanisms including TiC second phase pinning,MgO solute drag and Y2O3 grain boundary segregation.As a result,the Al2O3 matrix grain sizes reduced significantly from 5.12 μm to 1.82 μm and the fracture toughness of Al2O3-TiC ceramics increased from 3.99 ± 0.18 MPa·m^1 /2to 5.24 ± 0.22 MPa·m^1 /2.The results show that the microstructure of Al2O3 based ceramics can be refined significantly by the synergetic effects of multiple grain growth inhibition and consequently its mechanical properties will be improved.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2014年第9期2297-2301,共5页
Journal of Synthetic Crystals
基金
广东省引进领军人才专项资金(400120001)
广东省产学研结合项目(2009A090100015)
