| Polycrystalline Cubic Boron Nitride(PCBN), with the characteristics of high hardness, good wear resistance, difficult to iron group metal bonding, is widely used in cutting difficult materials, high-speed milling, hard cutting and other fields. At present, when milling hardened steel, gray cast iron and other difficult-to-cut materials, the being used cemented carbide face milling cutter is low in speed and the processing quality needs to be improved. Therefore, aiming at milling of hardened steel and cutting gray cast iron, the topic of this paper is on using PCBN as material, to design an effective face milling cutter, while there is still no successful trial cases on the market.First, in the article, the author analyses the characteristics of milling force and milling process to make detailed description of the mechanism, makes a theoretical analysis on the milling of single-tooth and multiple teeth milling force model,the relationship between the unit cutting force and dynamic cutting force spectrum. Basing on the principle of milling cutting and unit cutting force change on the impact of milling force spectrum, taking into account the experience of the value of tool design experience, the author designs an indexable face milling cutter for the milling of hardened steel and gray cast iron.On this basis, drawing out the manufacturing drawings of the PCBN indexable face milling cutter, combined with production practice, giving the face milling manufacturing program, and produce the face milling cutter.Then, for the processing of hardened steel, the author carries out cutting tests separately with the face milling cutter of PCBN and Carbide. Analysis indicates that: the performance of PCBN indexable face milling cutter is superior to carbide face milling cutter, if the cutting parameters is in a reasonable condition, its effects can be compared with the effect of grinding . Finally, by the test of PCBN cutting tools for milling of gray cast iron HT200, using least-squares method and principle of regression to establish the experience of the milling force model, analyzing the test results showed that the milling force in three directions: the largest one is the tangential cutting force Fz, followed by the Milling force Fx and radial cutting force Fy. And the milling force increases with the increasing of milling depth and the amount of feed per minute, and decreases with the increasing of spindle speed. |
