Dynamic stabilization of machining process based on local metastability in controlled robotic systems of CNC machines
- 1 — Ph.D., Dr.Sci. professor Saint-Petersburg Mining University
- 2 — Ph.D., Dr.Sci. professor Estonian University of Life Sciences
Abstract
The paper describes an effective method, which permits to control the machining of hard-to-handle materials under local pre-strain and facilitates generation of structural metastability on the outer layer of the process material. Authors propose a new approach to creating local metastability in the machined material using thermal, plastic and cryogenic treatment. Changes in material properties, occurring under local deformation, are presented in a widely used graphic form of a stress-strain curve. In experimental tests, performed under local plastic strain, the authors observed normal vibration displacement of the tool in relation to the surface of the workpiece, made of medium-carbon steel (0.45 % C). Theoretical and experimental results confirmed the possibility to control the cutting process and to deliver dynamic stability for high-precision machining. The study allows to improve existing technologies for a wide range of materials and cutting modes, to implement segmentation and breaking of the chip in the shear zone, and to apply controlled robotic systems on CNC machines.
References
- Anastasiadi P., Sil'nikov M.S. Steel Heterogeneity and Performance Characteristics. St. Petersburg: Izd-vo «Poligon», 2002, p. 624 (in Russian).
- Ashkenazi E.K. Anisotropy of Construction Materials: Spravochnik. Leningrad: Mashinostroenie, 1980, p. 148 (in Russian)
- Barmin V.N. Vibrations and Cutting Modes. Moscow: Mashinostroenie, 1985, p. 72 (in Russian).
- Borodkin M.M., Spektor E.N. X-Ray Texture Analysis of Metals and Alloys. Moscow: Metallurgija, 1981, p. 272 (in Russian).
- Vishnjakov Ja.D. Theory of Texture Formation for Metals and Alloys. Moscow: Nauka, 1979, p. 329 (in Russian).
- Vishnjakov Ja.D., Piskarev V.D. Residual Stress Control in Metals and Alloys. Moscow: Metallurgija, 1989, p. 254 (in Russian).
- Zolotorevskij A.S. Mechanical Properties of Metals. Moscow: Metallurgija, 1983, p. 352 (in Russian).
- Mikljaev P.T., Fridman Ja.B. Anisotropy of Mechanical Properties in Metals. Moscow: Metallurgija, 1986, p. 226 (in Russian).
- Aurich J.C., Bil H. 3D Finite Element Modelling of Segmented Chip Formation. CIRP Annals. 2006. Vol. 55/1, p. 47-50.
- Boothroyd G., Knight W.A. Boothroyd G. Fundamentals of Machining and Machine Tools. Boca Raton: CRC Press, 2006, p. 125
- Fang N., Jawahir I.S. An Analytical Predictive Model and Experimental Validation for Machining with Grooved Tools Incorporating the Effects of Strains, Strain-Rates, and Temperatures. CIRP Annals. 2002. Vol. 51/1, p. 83-86.
- Marusich T.D., Brand C.J. A Methodology for Simulation of Chip Breaking in Turning Processes Using an Orthogonal Finite Element Model. Proc. 5th CIRP Int. Workshop on Modeling of Machining Operations. West Lafayette. 2002, p. 139-148.
- Rahman M.A., Kumar A.S., Lim H.S. CNC Microturning: an Application to Miniaturization. J.Mach. Tools Manuf. 2005. Vol. 45, p. 631-639.
- Trent E.M., Wright P.K. Metal Cutting. Boston: Butterworth-Heinemann, 2000, p. 220.