Self-propagating high-temperature synthesis of boron phosphide
  A new method of producing boron phosphide (BP) submicron powders by self-propagating high-temperature reaction between boron phosphate and magnesium in the presence of an inert diluent (sodium chloride) has been proposed. Bulk polycrystalline BP with microhardness of HV = 28(2) GPa has been prepared by sintering the above powders at 7.7 GPa and 2600 K. 
Vladimir A. Mukhanov, Petr S. Sokolov, Yann Le Godec and Vladimir L.   Solozhenko
cond-mat.mtrl-sci