MICRO-SCRATCH FOR COATING ADHESION TEST OF NANO-STRUCTURED TiB2 COATINGS
Keywords:
Micro-scratch, nanoindentation, titanium diboride coating, adhesion, hardness, critical loadAbstract
TiB2-based nano-structured coatings were fabricated on high-speed steel by magnetron sputtering technique. Mechanical characterization of the resultant coating-substrate systems, such as, coating adhesion, friction and scratch resistance, was conducted by micro-scratch techniques. The linearlyincreasing load mode of the micro-scratch tests was studied to determine the most effective and informative testing conditions and to determine the critical load (Lc) for coating failure. The mode of failure was examined by high resolution SEM and AFM. By applying a small substrate bias and controlling the sputter-cleaning time, it was found the coating adhesion strength with high hardness was significantly improved.
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