放电等离子超快速烧结氧化物陶瓷

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-ZrO₂2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6MPa·m^1/2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．

Superfast Densification of Oxide Ceramics by Spark Plasma Sintering

The SPS (Spark Plasma Sintering) process is a new materials synthesis processing technology 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 then fast cooling to 600℃ within 3 minutes. The superfast sintering samples show high densities, fine microstructures and excellent mechanical properties. The fracture toughness K_1c of 20mol% Al₂O₃-ZrO₂(3Y) samples sintered by SPS at >1250℃ for 2 min is higher than 6MPa·m^1/2. The reaction sintering of ZrO₂- mullite could be completed by SPS at 1530℃ for 3 min.The SPS (Spark Plasma Sintering) process is a new materials synthesis processing technology recently developed by Sumitomo Coal Mining Co.Ltd., Japan. Some oxides such as Al_2O_3, Y-TZP, YAG, Al_2O_3-ZrO_2 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 then fast cooling to 600℃ within 3 minutes. The superfast sintering samples show high densities, fine microstructures and excellent mechanical properties. The fracture toughness K_1c of 20mol% Al₂O₃-ZrO₂(3Y) samples sintered by SPS at >1250℃ for 2 min is higher than 6MPa·m^1/2. The reaction sintering of ZrO₂- mullite could be completed by SPS at 1530℃ for 3 min.