Analysis on WC-8Co electro-spark deposition coating with powder presetting method

To improve the deficiencies in traditional electro-spark deposition(ESD) process,such as complicated preparation of electrodes and existence of cracks or holes in the coatings,a new ESD coating process was proposed by presetting WC-8Co powder in the plasma channal between the electrode and substrate.The surface morphology,microstructure and abrasion properties of the coating made with the new process were investigated and compared with the traditional ESD process.The results showed that the new process could produce a dense coating with low surface roughness which metallurgically bonded with the substrate.The coating prepared with the new process had better abrasion resistance than that with the traditional process.Preparation of ESD coating with powder presetting method could improve the efficiency of electro-spark deposition technique,and was suitable for producing coatings with large area.