Mechanical and magnetic properties of nano-Ni-20Fe tougheningalumina2based nanocomposites

Ni-20Fe/ Al₂O₃ nanocomposites with high relative density (D ≥98 %) were fabricated using the mechanochemical method and the hot-pressing process. The fracture toughness is increased f rom 4. 7 to 6. 2 MPa·m^1/2 asNi-20Fe volume f raction increases f rom 0 to 19 %. Both the intergranular and the t ransgranular f ractures areobserved on the f racture surface by FE-SEM. When 19 % Ni-20Fe is added , the composite Ms is 33 emu/ g , H_c is200 Oe , and H_c keep s constant below 500 ℃, which shows good magnetic heat stability.