Enhancement of mechanical and thermal properties in Zr–Cu–Ni–Al–N thin film metallic glass by compositional control of nitrogen

• Zr–Cu–Ni–Al–N thin film metallic glass with various compositions were fabricated via DC magnetron co-sputtering.
• The increase of N content significantly enhances thermal stability and hardness.
• Up to 14.1 at% N can be added without any crystallization.

The study is intended to investigate the optimal content of nitrogen in the Zr–Cu–Ni–Al–N thin film metallic glass (TFMG) to achieve the improved mechanical and thermal properties. Various Zr–Cu–Ni–Al–N TFMGs were fabricated by manipulating the nitrogen flow rate. It is revealed that the maximum content of nitrogen in the Zr–Cu–Ni–Al–N TFMG is 8.2 at%. The thin film with more than 8.2 at% nitrogen is no longer a metallic glass due to the absence of characteristic peak in DSC analysis. Within the metallic glass region, the mechanical performance and thermal stability are significantly improved as the nitrogen content increases.