摘要
添加分散的氧化锆对多晶体堇青石进行了增强和增韧。含10%(按质量计,下同)ZrO_2的氧化锆增韧堇青石陶瓷(ZTCC)的抗弯强度(130MP_a)较1400℃,6h制备的人工合成高纯多晶堇青石的(74.3MP_a)有明显提高。含有5%ZrO_2和1%CaO二元弥散相粒子的ZTCC的断裂韧性增大至2.83MPa·m^(1/2)。当加入15%Y-TZP,样品的抗弯强度和断裂韧性分别高达188MPa和3.2MPa·m_(1/2);增强和增韧的辐度分别为153%和100%。ZTCC的主要增韧机理为裂纹偏转和曲折扩展机理及曼徽裂纹增韧机理。含有ZrO_2弥散相的ZTCC保持了高纯堇青石陶瓷相同的抗热冲击破坏性能;而含有ZrO_2和CaO二元弥散相的ZTCC显示了更好的抗热冲击损伤性。
Strengthening and toughening of the polycrystalline cordierite ceramics adding with different amounts of ZrO_2 dispersed particles were investigated. Synthetic highly pure cordierite (HPC) (1400℃, 6h) has a very low linear thermal expansion coefficient of 1.54×10^(-6)/℃, a flexural strength of 74.3 MPa and a fracture toughness of 1. 60 MPa·m^(1/2). The flexural strength can be increased to 130 MPa by adding 10% (in mass) ZrO_2 dispersed particles in ZTCC, and the fracture toughness of ZTCC with adding 5% (in mass) ZrO_2 and 1% (in mass) CaO dispersed particles arrives at the level of 2. 83 MPa·m^(1/2). The effects of strengthening and toughening by adding superfine 15% (in mass) Y-TZP dispersed particles on ZTCC are so remarkable that the flexural strength and fracture toughness can be increased to 188 MPa and 3. 2 MPa·m^(1/2) respectively, which implies that the increase of strengthening and toughening is 153% and 100% respectively. The main toughening mechanism of ZTCC is the mechanism of crack deflection and microcracking. ZTCC containing ZrO_2 dispersed particles has the same thermal shock resistance as HPC ceramics, while ZTCC shows better thermal shock resistance by adding with ZrO_2 and CaO dispersed particles. It seems that ZTCC is suitable for the use of thermal-shock-resistant material because of its low thermal expansion and relatively good mechanical properties.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
1993年第5期399-405,共7页
Journal of The Chinese Ceramic Society
基金
西安交通大学材料开放研究实验室资助
关键词
堇青石
氧化锆
陶瓷
增韧
cordierite
zirconia toughened cordierite ceramics
zirconia
dispersed particle
toughening