In‐Situ Formation of Ce‐TZP‐M‐Type Hexaferrite Composites

Composites consisting of a Ce‐TZP matrix and in‐situ grown particles of La(Fe,Al) 12 O 19 were prepared by the solid‐state reaction of Ce‐TZP, La(Fe,Al)O 3 , and Al 2 O 3 powders. The in‐situ formation process of La(Fe,Al) 12 O 19 in a Ce‐TZP matrix was investigated in relation to the microstructure evolution. The Ce‐TZP‐La(Fe,Al) 12 O 19 composites had significant magnetic properties and improved mechanical properties. The maximum value of magnetization of the Ce‐TZP‐La(Fe,Al) 12 O 19 composites was obtained at 90 mol% LaFe 12 O 19 in La(Fe,Al) 12 O 19 . The value of the three‐point bending strength of Ce‐TZP‐20 wt% La(Fe,Al) 12 O 19 (90 mol% LaFe 12 O 19 ) sintered at 1350°C was 780 MPa, compared with 500 MPa of Ce‐TZP ceramics. The composite demonstrated crack sensing based upon the change in magnetic gradient.