| TiC based ceramic composite with high hardness and super wear resistance has been successfully developed by hot pressing for the use of wire-drawing dies. The design theory of this kind ceramic die material, the stress status inside the die during wire-drawing process, the key technologies the for die preparation, the wire-drawing testing equipment, and the failure mechanisms of the ceramic drawing dies have been studied extensively.TiC based ceramic composite with the additions of the Al2O3 and small volume fraction of metal phase was produced by hot pressing. The effect of the second phase content and the sintering parameters on the microstructure and mechanical properties of this kind die material has been studied. Results showed that this kind of die material had high hardness and super wear resistance. The optimum content of Al2O3 is 20 wt.%. The flexure strength of this kind of die material is 889MPa, the hardness is 19.1GPa, and the fracture toughness is 7.74MPa·m1/2. The optimum parameters for sintering (temperature 1700℃, temperature holding time 10 min, and pressure is 30 MPa.) for TiC based ceramic die material were obtained.An analysis model for the drawing force during wire-drawing processes is presented. The drawing forces in the TiC based ceramic drawing die were calculated. Result showed that the maximum drawing forces are generated near the exit at the bearing zone when drawing 65 Mn wire with a reduction ratio of 21%, and the maximum value of the force is 4219.52 N.A FEM analysis model for the stress and its distribution inside the ceramic die during wire-drawing processes was established. Results showed that the maximum axial stress is 317 MPa, the maximum radial stress is 2030 MPa and the maximum prime stress is 316 MPa. Effect of the entrance angle on the stress inside the ceramic drawing-die was analyzed by FEM simulation. Results showed that the optimum entrance angle of the ceramic drawing-die is 7°. The entrance angle should be increased...
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