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30％,PM排放降低18.8%,。The experimental results revealed that it is practicable to machine gray cast iron with single pulse interval laser micro-machining method by a Q switched diode-pumped solid-state (DPSS) Nd∶YAG laser. The effect of laser parameters (wavelength，light spot distance, overlap area factor and repetition frequency) on micro-machining quality was discussed. A desired micro-structure and surface quality could be achieved to overcome the adverse effect of thermal diffusion and prevent the melting and recasting efficiently. The section SEM of cutting grooves with JXA-840A was also analyzed. It is found that the treated layers of grooves have good joining state on the base metal. The optimized technology has been applied in the laser honing experiment. With the laser texturing of 4L88 diesel cylinder-bore surface, the oil consumption was reduced by 39.3%, the emission of combustion engines was reduced by 30%, and the particulate emission was reduced by 18.8%, comparing with traditional plateau honing.