Erosion resistance of TiB2–ZrB2 composites

Elemental powders of Ti, Zr, and B were combined by high-energy ball milling (HEBM) to produce fine single-phase (Ti,Zr)B2 powders of varying composition. The powders produced by HEBM also facilitate densification (99%) at hot-pressing temperatures as low as 1450 °C, which also aids in retaining a fine microstructure. By varying the hot-pressing parameters, a range of grain sizes was produced. ASTM-standard erosion and abrasion testing was performed on these wear-resistant samples to show the effect of grain size on wear resistance, and the results are compared with those for commercially available cemented tungsten carbide and cubic boron nitride. These results are also compared to those of similarly processed samples of TiB2. Erosion rates as low as 0.14 mm3/kg were recorded for Ti0.5Zr0.5B2 composites, compared with 0.51 mm3/kg for TiB2 prepared by a similar method, and 0.21 mm3/kg for wear-resistant, binderless WC.