摘要
用切口梁三点弯曲法测定了高于和低于相变温度的 BaTiO_3,VO_2和 BiSrCaCu_2O_y 多晶试样的平面应变断裂韧性 K_(lc)。结果表明,对于这几种材料,如果由于不纯净或掺杂而在低于相变温度下仍有部分高温相残留,则其韧性将得到改善。本文讨论了这种改善的原因。
Values of plane strain fracture toughess,for polycrystalline BaTiO_3,VO_2 and BiSrCaCu_2O_y have been measured by using three-point bending method aboveand below their phase transition temperatures.It is shown that toughnesss of the materialswill be improved below the phase transition temperatures if there remain some high tem-perature phases.
关键词
陶瓷
结构相变
韧性
断裂
金属
structure phase transition
superconducting transformation
fracture toughness
fracture surface energy
