Deposition of Diamond-Like Carbon Coatings on Surfaces of ZL114A Alloy Car Engine

The diamond-like carbon (DLC) coating were synthesized by magnetron co-sputtering on the ZL114 A-alloy substrate, an advanced car engine material and covered with Cr-transition layer.The influence of the Cr-transition layer and DLC thickness on the microstructures and tribological properties was investigated with scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, electrochemical workstation and conventional mechanical probes.The preliminary results show that the Cr-transition layer has a major impact.To be specific, the compact Cr (2 μm)/DLC (10 μm) coatings increased the micro-/nano-hardness of ZL114 A-alloy to 3.73 times/3.96 times, respectively, and significantly decreased the wear-rate, corrosion-rate and friction coefficient.Under the dry/wet friction conditions, the wear-resistance of the Cr-DLC coatings, higher than that of ZL114 A alloy, was high enough in wet friction of 3.5% NaCl solution.We suggest that the DLC coatings be of some technological interest in fabrication of car engine with ZL114 A alloy.