High speed milling of hardened mould processing key technology is introduced

In high speed milling mold, cutting tool technology, the most critical and important, mainly reflected in the cutting tool material and geometric parameters selection, tool damage and detection, the security of the bonding technique of cutting tool and machine tool, cutting tool, etc. Cutting tool material and geometric parameter selection (1 1) High speed milling tool material for high speed cutting tool materials and processing materials must have a smaller chemical affinity, good thermal stability, impact resistance, abrasion resistance and thermal fatigue resistance, and has excellent mechanical properties, etc. At present, hard for high speed milling tool material are polycrystalline cubic boron nitride ( PCBN) , ceramics, new types of cemented carbide and coated cemented carbide, etc. , should be based on the mould material, cutting tool geometry and cutting conditions, three main factors to select the cutting tool materials. Because of the polycrystalline cubic boron nitride ( PCBN) Tool has the very high hardness and wear resistance, which is suitable for high speed cutting hardened steel. When hardness is lower than 50 HRC of workpieces, PCBN cutting tool to form the chip for the runner, the cutting tool wear surface month, thus shortening the knives' service life. Therefore, PCBN cutting tools for machining material hardness higher than 55 ~ 65 HRC. Ceramic cutting tool cost lower than that of PCBN cutting tool, has good thermal chemical stability, but its toughness and hardness of PCBN cutting tools is better than good. Therefore, is suitable for ceramic cutting tool processing is relatively soft material ( HRC≤50） 。 New type cemented carbide carbide cutting tools and coating cost is low, but the hardness as PCBN cutting tool and ceramic cutting tool, generally between 40 ~ 50 HRC. From the current research situation in all mold in high speed cutting tool material, polycrystalline cubic boron nitride ( PCBN) Cutting tools with good performance, is the main tool for hardened steel mold processing materials. ( 2) Cutting tool geometry parameter choice when the cutting tool material is selected, the selection of geometric parameters of cutter for cutting tool life and cutting speed has a great influence, generally should choose the blade shape of strength as far as possible big, tip radius of circular arc is as large as possible. In addition, the cutting force of hard cutting big, in addition to the blade strength requirements, to tool rod strength and stiffness requirement is high also. 2 tool damage and detection, 1) Cutter damage due to the high speed milling cutter price is more expensive, tool damage serious shorten the service life of the cutter, increase the cost of high speed milling. Control tool damage, therefore, strengthen the detection for high speed milling cutter is of great significance. Cutting tool damage situation has two kinds of wear and tear. Wear is a tool in the process of machining and the surface of the workpiece, the contact and friction material consumption phenomenon; Breakage is tool collapse edge, fracture, plastic deformation and so on so the loss of cutting ability, it includes the brittleness damage and plastic damage. Tool wear in high speed milling is a difficult problem to be resolved. When high speed milling tool wear are mainly after the blade wear, rake face of crater wear, boundary wear, micro collapse edge, exfoliate, plastic deformation, etc. Different processing materials and the main wear different form of high-speed cutting tool material. After the blade wear is the most common form of high speed cutting tool wear, also is normal wear form of cutting tool, general cutters even wear zone width after using VB value as the limit of tool wear.