Method to increase the active contents of partially oxidized boron particles and performance of B/PB₃O₄ composites with treated boron

The treatment of partially oxidized boron was investigated to increase the active boron contents. Longstored boron samples were washed by distilled water and ethanol. The washed boron samples were termed B_W (with water) and B_E (with ethanol), then B_W and B_E were separately mixed with lead oxide (Pb₃O₄) to form B/Pb₃O₄ composites. The mass fractions of boron in B/Pb₃O₄ composites were 2, 2.5, 3, 3.5, 4, 4.5, and 5 wt %. B/Pb₃O₄ composites were loaded into iron tubes and consolidated with a pressure of 312.5 MPa. The combustion time of B/Pb₃O₄ composite was measured by the optical target method. Results show that the burning rate of B_E/Pb₃O₄ composite is on average 2.2 times of the burning rate of B_W/Pb₃O₄. Thermogravimetry and differential scanning calorimetry were conducted to compare the thermal decomposition reaction and the stability of the B_W/Pb₃O₄ and B_E/Pb₃O₄ composites.