Properties of Al₂O₃/(W,Cr) Cermet for Hot Extrusion Die

Al2O3/(W, Cr) cermet with different Al2O3 contents for hot extrusion die was prepared by hot pressing method. The mechanical properties, thermal shock resistance and friction and wear properties of the cermet were investigated. The results show that the maximal bending strength and fracture toughness of the Al2O3/(W, Cr) cermet reached 800 MPa and 13 MPa·m1/2. The thermal shock resistance of the cermet with 60vol% Al2O3 was superior to that of the one with 70vol% Al2O3, the friction coefficient of both the cermets decreased with the increase of normal load and increased with the prolongation of friction time. The wear rate increased with increasing the normal load. The main wear mechanisms of the cermet were adhesive wear with abrasive wear.