**8. Summary**

98 Tungsten Carbide – Processing and Applications

properties during dry abrasion.

the best area of application for zirconia composites. Alumina based materials show the best

**Figure 17.** A typical microstructures of worn surfaces after Dry Sand Test; alumina (left top), zirconia s.

Material Miller Test Dry Sand Test

Alumina 0,66 ±0,11 1,02 ±0,05 Alumina/10vol.% WC 0,28 ±0,05 0,50 ±0,02 Zirconia s.s. 0,61 ±0,03 0,71 ±0,04 Zirconia/10vol.% WC 1,00 ±0,14 1,12 ±0,09

Ra [μm] Ra [μm]

s. (right top), alumina/10vol.% WC (left bottom), zirconia/10vol.% WC (right bottom).

**Table 5.** Profilographic parameter Ra of material surfaces worn during wear tests.

± denotes of the standard deviation of 5 measurements

Selected information about properties of composite materials basing on alumina or zirconia matrices containing dispersed tungsten carbide inclusions presented in this chapter indicated that these materials have potential to be widely used as a structural material.

Properties improvement in these composites is not only an effect of introducing an additional toughening mechanisms connected with crack path/inclusion interacting (crack deflection, crack branching, crack bridging), but also relatively strong interphase grain boundaries confirmed by the unique phenomenon of privileged crystallographic correlation of oxide and carbide phases.

Their very good properties are manifest in applications connected with intensive wear risks, especially in the presence of loose, hard particles. Spectacular improvement was also observed in prolonged applications at conditions under stresses much lower than critical at wet or high humid environments.

Tungsten Carbide as an Reinforcement in Structural Oxide-Matrix Composites 101

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