According to the principle of the experimental modal analysis, this study is based on tool system of the MIKRON UCP 710 numerical control machining center as test object for experimental modal analysis. Using the integral polynomial recognition method to identify the modal parameters (natural frequency, structural damping, and modal shape), and finally matching the results with the vector analysis method and the finite element simulation method. The results show that integral polynomial recognition method has higher precision than the vector analysis method to identify the multi-degree of freedom system; the experimental modal analysis can also obtain better modal parameters of the structure system, and a higher precision than the finite element simulation method. Obtained the MIKRON UCP 710 high-speed milling center tool system accurate modal parameters provides the necessary theoretical and experimental basis for the further study of the stability properties in the cutting processing of the high speed machining tool system.

A method to identify the effect of tool overhang on vibration signal is put forward to study machining process of large hardened steel automobile mold by wavelet energy spectrum. Firstly, collect the machinery vibration signal on milling by displacement sensor, then make a wavelet transform on time signal and calculate the wavelet energy spectrum of each frequency range. Finally, extract energy value of the right frequency by the method of homogenization. It is confirmed by experimental data that this method can recognize vibration feature and abnormal condition of cutting tool in high speed milling process of hardened steel fleetly and efficiently.

A model is established with considering the vibration effect of microstructure on milling surface formation, the impact of vibration on surface profile formation is also studied, which is simulated by the approach of vibration displacement in actual measurement. The on line monitoring of cutting vibration can be realized efficiently by the above method, and it is a coincident microstructure of milling surface between simulation and actual processing. In the result, it is cutting vibration that plays an main role in microstructure of milling surface formation with the known cutting parameters.

As cutter radial runout and deformation play a main role in processing precision, surface roughness and cutter wear during hard milling, the effects of the former two factors on actual cutting radius and cutting chip thickness are analyzed during milling process briefly in this paper. The vector direction of radius runout and deformation are assumed to be the same. Then, the milling force of cutting cutter whirling a circle is simulated under the three-dimensional feed motion, and the simulation result agrees well with the experimental result.

Firstly, with studying three typical aspects as cutting force, cutting temperature and chip breaking behavior, contrast experiments of machinability were made on hydrogenated cylindrical shell materials (2.25Cr-1Mo-0.25V), 45 steel, and stainless steel (1Cr18Ni9Ti). The experiment results show that the depth of cut ap have a larger effect on the main cutting force FZ and the cutting temperature θ than the affection of the feedrate f, for that reason, in order to reduce the main cutting force FZ and the cutting temperature θ, large feedrate situation will be better for machining work of hydrogenated cylindrical shell materials. When cutting hydrogenated cylindrical shell materials , many difficult points appearance, such as large cutting force, high cutting temperature, serious chips winding, chips difficult to break etc, which has worse machinability even than stainless steel(1Cr18Ni9Ti).