Protective TiC coating was produced on Cr-Zr-Cu electrode by vibrating electrospark deposition. Microstructure of the functional coating with pre-treatment (clean) and post-treatment (diffusion) were tested respectively. The deposition parameters on the structure of the substrate is discussed. The results indicate that as-deposited substrate consists of four layers. There are many micro-porous and micro-cracks in transition layer where mutual diffusion of Ti and Cu occurs, which provides atomic bonding between the coating and the substrate. Pre-treatment modifies the coating structure with small influence on its hardness whereas post-treatment modifies it and reduces its hardness and thickness. The service time of the specimens with TiC coating 2.4 times exceeds that of the uncoated ones.