Abstract:For the problem of poor processing performance andsevere tool wear of hardtomanufactured material 300M steel

highspeed milling300M steel tool wear test of dry and CMQL was carried out. The wear morphologyof the tool was observed with an ultradeepdepth microscope

and the wearmechanism of the tool was analyzed with a scanning electron microscope (SEM).The results show that PVD coatings protect the tool better than uncoated andCVD coated tools; When the cold air temperature is -45℃

the air pressure is 0.7MPa

and the oil volume is 40mL/h

the effect of CMQLtechnology is the best; When considering the processing quality and processingefficiency

the milling speed is set to 400m/min; Compared to dry cutting

CMQLtechnology can effectively reduce abrasive wear of the blade

bond wear on theblade surface

oxidative wear at the flank boundary

and mild diffusion wear.