Preparation and Research of Composite Materials of the Al2O3–ZrO2–La2O3 System

Introduction of lanthanum oxide into an aluminum-zirconium matrix leads to the formation of LaAl 11 O 18 during sintering in air at 1520°C for 2 h. The grain size of aluminum oxide is at the level of 0.75 μm. The highest crack resistance (6.2 ± 0.3 MPa·m 1/2 ) with the selected technological parameters for obtaining the materials is found for the material with 3 wt.% LaAl 11 O 18 . The critical stress intensity coefficient of such material is 24% higher than that of aluminum-zirconium ceramics without additives.