Abstract:
The alumina extruded metal-ceramic die materials used for the robot cover were prepared by the hot-pressing sintering, using the micro-size Al
2O
3 as the main material and the micro-size Cr and W as the main additives. The strength, fracture toughness, hardness, and wear resistance of the metal-ceramic die materials were studied, and the wear surface microstructure of the materials was analyzed. The results show that, when the mass fraction of the micro-size Al
2O
3 is 65%, the mass fractions of the micro-size W and Cr are both 12.5%, and the sintering temperature are 1640 ℃, the prepared samples can achieve the best combination properties, as the relative density, bending strength, fracture toughness, and hardness is 99.8%, 805.6 MPa, 14.5 MPa·m
1/2, and 11.2 GPa respectively. At the same time, the second phases formed by metal W and Cr can produce the mechanical cold welding in the process of friction and wear, which greatly improves the wear resistance of the die materials.