Sintering Strengthening Mechanism of MgO Sintering Additives Added in Fabricating Al₂O₃ Ceramics Using Binder Jetting

Binder jetting is an emerging additive manufacturing technique suitable for fabricating Al 2 O 3 ceramics. Nevertheless, the strength of parts produced via this method limits development for Al 2 O 3 ceramic production. This study investigates sintering additives to enhance Al 2 O 3 ceramic sintering and strength. Al 2 O 3 samples with varying MgO content are fabricated. Adding a single MgO sintering additive increased Al 2 O 3 resilience to 0.2 MPa. Furthermore, incorporating small grain size MgAl 2 O 4 and ZrO 2 as strengthening methods is explored. The results demonstrate that while MgO‐reinforced Al 2 O 3 is well‐suited for binder jetting, the combined use of MgAl 2 O 4 and ZrO 2 significantly enhances material strength, achieving improvements of 2.7 and 6.6 times, respectively. A comparative analysis of the microstructural and surface morphological effects of MgO, MgAl 2 O 4 , and secondary phase content on Al 2 O 3 ceramics is conducted, providing insights into the strengthening mechanisms.