A study on preparation of Al/DyPO₄ composite and its property

Aluminum powders coated by dysprosium phosphate(DyPO₄) is synthesized by heterogeneous precipitation using dysprosium nitrate and ammonium dihydrogen phosphate as raw materials. The morphology, structure, optic and infrared properties of these composite particles are characterized. The low infrared emissivity and special absorption at certain wavelengths of the composite particles can be adjusted by varying reactants' concentration and reacting temperature. When mass concentration of aluminum is 16.67 g/L, molar concentration of DyPO₄ and NH₄H₂PO₄ each is 0.014 mol/L, the infrared emissivity of composite particles can be 0.70, which is decreased by 24% compared with the pure DyPO₄, and has characteristic absorption and low reflectivity at wavelength of 810, 908, 1100, 1290 nm.