Parameter optimisation of Ti-DLC coatings using statistically based methods

The influence of process parameters on the mechanical properties of magnetr on-sputtered Ti-C:H films was investigated using fractional factorial exper imental design. The parameters studied included substrate bias voltage, ace tylene flow rate, and argon and nitrogen partial pressures. The results ind icated that bias voltages in the range -20 to -60 V had little or no influe nce on the mechanical properties. The acetylene flow rate, which controlled the titanium content in the Ti-C:H layers, exhibited the most significant effect. An explanation based on the relationship between relative film thic kness and critical applied loads is provided for the coating failure mechan isms. (C) 1999 Elsevier Science S.A. FLU lights reserved.