Studying The Microstructure And Mechanical Properties Of (Wc - Tic - Co) /Zro2 Composite Prepared By Powder Technology

Manufacture of composite materials has become an important issue in recent years due to their high mechanical properties that make them suitable for many applications which needs high wear resistance and high strength. In the present work, (WC-TiC-Co) with 3,6,9,12,15, and20 wt% ZrO2 composites were prepared by mechanical milling. The mixed powders were pressed in a unixial press and sintered at 1450 degrees C for two different times 1.5 and 3 hrs. The results indicated that the relative density decreases gradually by increasing ZrO2 percent for both sintering times. The microstructure of WC-TiC-Co/ ZrO2 composites indicated the formation of needle shape particles from 0 9 wt % ZrO2 samples for 1.5 hr sintering time and disappeared for the others sintered for 3 hrs . Hardness, compression strength, and transverse rupture strength decreased by increasing ZrO2 percent for all samples, but both the wear resistance and fracture toughness increased gradually by increasing ZrO2 wt% up to 9 wt% and then decreased for the higher percents.