Stainless steel is widely used, but because stainless steel has different characteristics from other general materials, the processing of stainless steel has become a big problem for technicians!

The adhesion and fusion of stainless steel are strong, and the chips are easy to adhere to the cutting edge of the milling cutter, which deteriorates the cutting conditions. When the milling is performed, the cutting edge first slides on the hardened surface, which increases the tendency of work hardening; The impact and vibration during milling are large, which makes the milling cutter blade easy to chip and wear.

Milling stainless steel except end mills and some end mills and carbide as milling materials, all other types of milling cutters are made of high speed steel, especially tungsten & mdash; molybdenum and high vanadium high speed steel have good The effect is that the tool durability can be increased by 1 to 2 times than the W18Cr4V. The carbide grades suitable for making stainless steel milling cutters are YG8, YW2, 813, 798, YS2T, YS30, YS25, etc. The cutting edge must be sharp and bear the impact, and the chip pocket should be large. Large helical angle milling cutters (cylindrical milling cutters, end mills) can be used. The screw angle b is increased from 20° to 45° (gn=5°), and the tool durability can be increased by more than 2 times because the milling cutter works at this time. The rake angle g0e is increased from 11 & deg; to 27 & deg; above, milling is brisk. However, the value of b should not be large, especially for end mills with b≤35° to avoid weakening the teeth.

The stainless steel pipe or thin-walled parts are machined with a wave-edge end mill. The cutting is light, the vibration is small, the chips are brittle, and the workpiece is not deformed. High-speed milling with carbide end mills and milling of stainless steel with indexable end mills have achieved good results.

Milling 1Cr18Ni9Ti with a silver-white end mill with geometric parameters gf=5°, gp=15°, af=15°, ap=5°, kr=55°, k′r=35°, g01= -30°, bg=0.4 mm, re=6 mm, when Vc=50-90 m/min, Vf=630-750 mm/min, a′ p=2-6 mm and the feed amount per tooth reaches 0.4-0.8 mm, The milling force is reduced by 10% to 15%, the milling power is reduced by 44%, and the efficiency is greatly improved. The principle is that the negative chamfer is ground on the main cutting edge, and the built-up edge is artificially generated during milling, so that it can be cut instead of the cutting edge. The front angle gb of the built-up edge can reach 20~~302, due to the lead angle The effect is that the built-up edge is caused by the thrust generated on the rake face parallel to the cutting edge to become the auxiliary chip, thereby taking away the cutting heat and lowering the cutting temperature.

When milling stainless steel, it should be processed by the down-cut method whenever possible. The asymmetrical cross-milling method can ensure that the cutting edge is smoothly cut away from the metal, and the contact area of ??the chip bonding is small, and it is easy to be smashed under the action of high-speed centrifugal force, so that the chip impacts the rake face when the tooth re-cuts into the workpiece. Peeling and chipping improve the durability of the tool.

The effect of spray cooling is the most significant, which can increase the durability of the milling cutter by more than one time; if it is cooled by a general 10% emulsion, the cutting fluid flow should be sufficiently cooled. When milling carbide with carbide milling cutter, take Vc=70～150m/min, Vf=37.5～150mm/min, and adjust it according to the alloy grade and workpiece material.