烧成制度及杂质对Mg-PSZ材料析出体形态和力学性能的影响

Effect of Sintering Processes and Impurities on Precipitate Sizes and Mechanical Properties of Magnesia-Partially-Stabilized Zirconia (Mg-PSZ)

以阳泉产ＺｒＯ２ 原料为研究对象，通过控制烧成制度，即在烧结温度前保温（１６００ ℃） ，再在Ｃ 相区烧结固溶，经慢速冷却至１１００ ℃后再自然冷却到室温，可使基体中长出大小合适的析出体，获得较佳的力学性能。含１０ｍｏｌ％ ＭｇＯ 的 Ｍｇ － ＰＳＺ 材料强度可达７２８ ＭＰａ，韧性可达１２ ．３ ＭＰａ·ｍ１／２ ，与宜兴料相比较，可知少量杂质（Ｆｅ２Ｏ３） 可略降低材料的烧结温度，但对材料的力学性能无影响。通过ＳＥＭ 对选用不同烧成制度材料中析出体的形态进行了分析。

Mg-PSZ material using Yang Quan zirconia was prepared by controlling the sintering processes,i.e.,before the material sintering at solution temperature,it was held for 2 hours at 1600℃ during the heating process,and then it was cooled at 120℃/h to 1100℃ from the sintering temperature.The bending strength and fracture toughness of Mg-PSZ (10mol%MgO) reached 728MPa and 12.3MPa·m 1/2 respectively.Compared with Yi Xing ZrO 2 material,Yang Quan ZrO 2 with a little impurity (Fe 2O 3) could be completely sintered at a lower temperature 1680℃,but the mechanical properties were almost the same compared with those of Yi Xing zirconia.The different precipitate sizes caused by different sintering processes were observed using SEM.The microstructure showed that the precipitates were homogeneously dispersed in the cubic grains and developed to a suitable dimension.