Effect of N₂-Flow Rate and Annealing Temperature on Properties Zr-B-N Nano-Composite Coatings

The Zr-B-N coatings were synthesized by high power impulse and pulsed DC magnetron sputtering on substrate of Si wafer. The influence of the N₂ flow-rate and annealing temperature on the microstructures and properties of the Zr-B-N coatings was investigated with X-ray diffraction, scanning electron microscopy and electron probe microanalysis. The results show that the N₂ flow-rate and annealing temperature had a major impact. For example, annealed at 600 ℃ in air, quite a few < 116 > oriented Zr₃O grains formed on the surface; deposited at the flow-rate of 6 m L/min, the amorphous phase dominated the annealed Zr-B-N coatings; as the annealing temperature increased, the coatings, grown at 10 m L/min, became much less compact because of increasing surface oxidation.We found that a higher N₂ partial pressure produced more compact coating and stronger oxidation resistance; and annealing at 800℃ resulted in serious cracking and peeling-off.