Mechanical properties, sliding wear and solid particle erosion behaviors of plasma enhanced magnetron sputtering CrSiCN coating systems

CrSiCN coating systems with different concentrations of Cr, Si, C, and N were investigated for their microstructure, mechanical properties (hardness H, elastic modulus E and indentation fracture toughness K_IC) and tribological behaviors using SEM, nano-indentation, indentation, pin-on-disk wear test, and sand particle erosion test. The wear behaviors, such as specific wear rate and Archard wear coefficient, showed inverse relationships with H³/E² ratio, confirming that the resistance to plastic deformation is the essential factor governing sliding wear behavior. High H³/E² ratios also contributed to increased resistances to erosion at low impingement angles. However, at higher impingement angles (>60°), coatings with lower index of brittleness (B=2.656μm^-1/2), higher critical load (P^*=6.670N) for crack initiation and fracture surface energy (γ_f=0.123Jm^-2) offered a higher erosion resistance. The indentation fracture toughness (K_IC), hardness (H) and elastic modulus (E) are limited to interpret erosion behaviors in a comprehensive approach, suggesting that erosion is a complex process where multiple mechanical properties contribute to erosion performance.