Figure 1
From: Hardness of Polycrystalline Wurtzite Boron Nitride (wBN) Compacts

(a) Transformation pressure-temperature diagram of wBN (Red circle: cBN, Black rhombus: wBN, Green triangle: wBN + cBN). (b) XRD patterns of the starting wBN, and the synthesis products synthesized at 20 GPa and 1,150 °C, 1,250 °C and 1,850 °C, respectively. (c) XRD patterns of hBN and wBN.