In order to probe into the machinability of hardened steel, the finish turning of quenched AISIH13 steel was performed with YW2A fine cemented carbide cutters,and OM,Dynamometer (YDC-Ⅲ 89B),tool microscope (XGJ-1),scanning electron microscopy (JSM5800LV), and portable roughness tester (TR100) were used to study the effect laws of cutting speed on chip formation,cutting force, tool wear and surface roughness of parts. The results showed that the chip evolves from continuity strip to C type segment, and the cutting force, flank wear and part surface roughness decrease with the increase of cutting speed.The adhesive,oxidation and diffusion wear are dominated in the rake face,the cutting temperature is the main reason, while the fatigue spalling plays a leading role,the mechanical stress is the dominant effect in the range of trial cutting speed.
