放电等离子超快速烧结氧化物陶瓷

Superfast Densification of Oxide Ceramics by Spark Plasma Sintering

本文介绍一种氧化物陶瓷超快速烧结的新方法．用放电等离子烧结的方法对Al2O3、Y-TZP、YAG、Al2O3-ZrO2和莫来石等各种氧化物粉体进行了超快速烧结，采用2～3min升温到1200℃以上，不保温或保温2min，然后迅即在3min之内冷却至600℃以下的烧结温度，得到了直径为20mm的晶粒细、致密度高、力学性能好的烧结样品．对用化学共沉淀法自制的20mol％Al2O3-ZrO2（3Y）纳米粉体分别在1170～1500℃之间的7个不同温度下进行放电等离子烧结，升温速率为200℃／min，保温2min后；迅即在3min之内强制冷却至600℃以下．1350℃以上烧结得到的样品密度已接近理论密度，1250℃以上烧结得到的样品的断裂韧性K1c都大于6MPam1／2放电等离子超快速反应烧结所得到的ZrO2-莫来石复相陶瓷致密度高、力学性能好，ZrO2晶粒在莫来石基体中分布均匀,XRD结果表明，在1530℃烧结的样品中，已找不到ZrsiO4痕迹，说明在如此快速的烧结条件下；反应烧结已经可以完成．

The SPS (Spark Plasma Sintering) Process is a new materials synthesis procussing techllology recently developed by Sumitomo Coal Mining Co.Ltd.. Japan. Some oxides such as Al2O3, Y-TZP,YAG, Al2O3-ZrO2 and Mullite were successfully superfast densified by SPS under the conditions of heating rate as high as 600℃/min, no keeping time at the sintering temperatures above 1200℃,and thed fast cooling to 600℃ within 3 minutes. The superfast sintering samples show high densities, fine inicrostructures and excellent mechanical properties. The fracture toughness K1c of 20mol% Al2O3-ZrO2 (3Y) samples sinterse by SPS at> 1250℃ for 2 min is higher than 6MPa.m1/2.The reaction sintering of ZrO2- mullitc could be completed by SPS at 1530℃ for 3 min.