Anti wear property of GCr15 steel deposited with Ta film and implanted with C ions

Tantalum films of 100-nm thickness were deposited on GCr15 bearing steel by magnetron sputtering. The films were implanted to different doses of 50 keV carbon ions by plasma-based ion implantation. Wear resistance test were performed on ball-disk friction tester with Φ6 mm GCr15 steel balls. X-ray diffraction patterns showed that the modified layers contained Ta2C, and TaC appeared at increased doses. Wear property of the modified GCr15 steel was improved, according to scanning electron microscopy images of the wear trace and abrasive debris. Under 1N load and 50 mm/s sliding speed, in comparison with the control, anti wear property of the sample deposited with Ta film and implanted with 3 x 1017/cm2 carbon ions increased by a factor of 1.65, and the friction coefficient decreased from 0.8-1 to 0.5 after Ta film deposition, and decreased further to 0.2-0.3 after the carbon ion implantation. It was found that the main wear mechanism is abrasive wear. (authors)