The Machining Features for Hard-to-be-Machined Materials
1)The heavy machining force:it is 1.5~2.5 times than the 45# steel.
2)The high machining temperature:when Vc=75m/min,the machining temperature to turning the below materials is much higher than the 45# steel.
TC-4 435℃,GH132 320℃, GH36 270℃,1Cr18Ni9Ti 195℃
3)High machining-harden tendency,as the high toughness,plasticity,enhancement coefficient for some hard-to-be-machined materials,adding absorbtion of the H,O,and N etc atom from surrounding medium with the function of machining heat,resulted in hard and fragile layer on the machining and machined surface,which hardness is 50~200% higher than the substrate with depth 0.1mm more,it is several times than the 45# steel.
