Abstract The objective of this research is to test a hypothesis that particle coating increases the sinterability of ceramic powder. This method is developed for binder jetting additive manufacturing but tested using a pressing and sintering route for the simplicity. Binder jetting additive manufacturing has demonstrated its considerable capability in manufacturing ceramic parts with a complex shape and/or a customized design. Currently, the density of the ceramic parts made by binder jetting is low and their mechanical properties are inferior. The main reason is the low sinterability of the powder feedstock. A new powder surface modification method, i.e., particle coating, was applied to increase the powder sinterability and the part strength. Specifically, coarse crystalline alumina particles (70 and 10 µm in average) were coated with amorphous alumina, in which the microsized core was designed to provide the high flowability and the amorphous shell to promote sintering due to its high activity. The coated powder was pressed into disk samples and sintered. The samples from the coated powder showed significantly higher shrinkage and compressive strength than those from the raw powder, which proved the feasibility of the particle coating method to increase the powder sinterability and part strength.

中文翻译：

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陶瓷粘合剂喷射增材制造：用于提高粉末可烧结性和部件强度的颗粒封装

摘要 本研究的目的是检验粒子涂层提高陶瓷粉末可烧结性的假设。这种方法是为粘合剂喷射增材制造而开发的，但为了简单起见，使用压制和烧结路线进行了测试。粘合剂喷射增材制造已证明其在制造具有复杂形状和/或定制设计的陶瓷部件方面具有相当大的能力。目前，粘结剂喷射制得的陶瓷零件密度低，力学性能较差。主要原因是粉末原料的可烧结性低。应用了一种新的粉末表面改性方法，即粒子涂层，以提高粉末的可烧结性和零件强度。具体来说，粗晶氧化铝颗粒（平均 70 和 10 µm）被无定形氧化铝包覆，其中设计的微型核提供高流动性，无定形壳由于其高活性而促进烧结。将涂覆的粉末压成圆盘样品并烧结。包覆粉末样品的收缩率和抗压强度显着高于原料粉末，这证明了颗粒包覆法提高粉末可烧结性和零件强度的可行性。