Combustion-aminolysis synthesis and characterization of CrN/Cu composites

CrN/Cu composite powders were synthesized by employing a novel two-step technique. Firstly, the Cr2O3+CuO precursors were prepared by the solution combustion synthesis (SCS) method using cupric nitrate, urea, and chromium nitrate as initial materials. Subsequently, the SCS precursors were calcined at 850 °C in NH3 for 6 h, and transformed to CrN/Cu composite powders. The composite powders consist of the uniform subsphaeroidal particles with the particle size ranging from 200 to 300 nm. After the friction-wear test, the removal volume of the sintered CrN/Cu composite specimen (0.0218 mm3) is almost 80 times smaller than that of the sintered pure copper specimen (1.6634 mm3). The addition of CrN can improve the tribological performance of sintered copper significantly. Moreover, the electrical conductivity of the sintered CrN/Cu composite specimen is high to 85.6% of IACS (International Annealed Copper Standard).