Electric-spark deposition (ESD) was adopted for depositing a Ti( CN) -based ceramic coating on the TC4 titanium alloy substrate using a laboratory-developed electric-spark deposition system, a nitrogen-sealed atmo...Electric-spark deposition (ESD) was adopted for depositing a Ti( CN) -based ceramic coating on the TC4 titanium alloy substrate using a laboratory-developed electric-spark deposition system, a nitrogen-sealed atmosphere and graphite electrode. The surface morphology, microstructure, interfacial behavior between the coatings and substrate, phase and element composition of the coatings were investigated by scanning electron microscope ( SEM ) , X-ray diffraction ( XRD ) , X-ray photoelectron spectroscopy ( XPS ) and Auger electron spectroscopy ( AES ) . Microhardness profile was measured with a Vickers microhardness tester. The results show that metallurgical bond between the coating and substrate is realized and the phase of coatings are made up of Ti( CN ) spherocrystal and dendritic crystal, TiV and C. Ti( CN) ceramic particles, which is in-situ synthesized by the reaction among titanium from the substrate, carbon from the graphite electrode and nitrogen from the shielding nitrogen gas, is about 600 mn and distributes dispersively among the coatings. Microharduess profile falls off with the coatings thickness increasing and the highest microhardness values of the superficial coating could be up to 1 496HV, which is six times more than that of the substrate.展开更多
基金The work was supported by the Natural Science Foundation of Hebei Province of China under Grant No. E2007000566.
文摘Electric-spark deposition (ESD) was adopted for depositing a Ti( CN) -based ceramic coating on the TC4 titanium alloy substrate using a laboratory-developed electric-spark deposition system, a nitrogen-sealed atmosphere and graphite electrode. The surface morphology, microstructure, interfacial behavior between the coatings and substrate, phase and element composition of the coatings were investigated by scanning electron microscope ( SEM ) , X-ray diffraction ( XRD ) , X-ray photoelectron spectroscopy ( XPS ) and Auger electron spectroscopy ( AES ) . Microhardness profile was measured with a Vickers microhardness tester. The results show that metallurgical bond between the coating and substrate is realized and the phase of coatings are made up of Ti( CN ) spherocrystal and dendritic crystal, TiV and C. Ti( CN) ceramic particles, which is in-situ synthesized by the reaction among titanium from the substrate, carbon from the graphite electrode and nitrogen from the shielding nitrogen gas, is about 600 mn and distributes dispersively among the coatings. Microharduess profile falls off with the coatings thickness increasing and the highest microhardness values of the superficial coating could be up to 1 496HV, which is six times more than that of the substrate.