Boston R, Guo J, Funahashi S, Baker A L, Reaney I M, Randall C A
Materials Science and Engineering, University of Sheffield S1 3JD UK
Materials Research Institute and Department of Materials Science and Engineering, The Pennsylvania State University PA16802 USA.
RSC Adv. 2018 Jun 4;8(36):20372-20378. doi: 10.1039/c8ra03072c. eCollection 2018 May 30.
Dense (>96% theoretical) strontium titanate ceramics were fabricated at 950 °C (conventional sintering temperature > 1400 °C) using a reactive intermediate phase cold sintering process. An aqueous solution of SrCl mixed with TiO nanoparticles was added to SrTiO powders and pressed at 180 °C to obtain a highly compacted green body. During the post-press heating step at 950 °C, the TiO and SrCl create in-filling micro-reactions around each grain resulting in dense (>96%) SrTiO ceramics. Nano- and micron-sized starting powders were used, demonstrating that this reactive intermediate phase cold sintering route can densify a wide range of starting powder sizes, as it not reliant on an amorphous-to-crystalline precipitation through the terrace ledge kink mechanism, as has been identified repeatedly in previous cold sintering mechanisms. Moreover, this process has the potential to densify a wide variety of functional oxides, as a range of different low-temperature chemical synthesis routes could be used.
采用反应性中间相冷烧结工艺，在950℃（传统烧结温度>1400℃）下制备了致密（>96%理论密度）的钛酸锶陶瓷。将与TiO纳米颗粒混合的SrCl水溶液添加到SrTiO粉末中，并在180℃下压制成高度致密的生坯。在950℃的压后加热步骤中，TiO和SrCl在每个晶粒周围产生填充微反应，从而得到致密（>96%）的SrTiO陶瓷。使用了纳米级和微米级的起始粉末，这表明这种反应性中间相冷烧结路线可以使各种起始粉末尺寸致密化，因为它不依赖于通过台阶边缘扭结机制从非晶态到晶态的沉淀，而这在以前的冷烧结机制中已被反复确认。此外，由于可以使用一系列不同的低温化学合成路线，该工艺有可能使各种功能氧化物致密化。
