通过对不同密度的Ｙ—ＴＺＰ（钇稳定四方相氧化锆多晶体）材料的力学性能（强度、韧性及硬度）和断裂时相变性能的研究，发现材料的相对密度不仅直接影响其力学性能，而且影响断裂时断口四方相向单斜相的相变量材料密度越高，相交量越大，材料密度和断裂时断口相交量共同决定了材料的力学性能 Through the study of mechanical properties (strength, toughness and hardness) and fracture toughness of Y-TZP (yttrium-stabilized tetragonal zirconia polycrystal) with different densities, it is found that the relative density of the material not only directly affects its mechanical properties, Moreover, the higher the density of phase change material, the larger the intersection volume, the material density and the fracture volume at the fracture determine the mechanical properties of the material