Friction on the Tool-chip Interface Under Liquid Nitrogen Cooling

공구와 칩 사이에서의 Liquid Nitrogen의 마찰 효과

  • Published : 2002.06.01

Abstract

A cutting fluid can improve machining quality and tool life by maintaining the tool toughness and by providing a lubrication effect to reduce the friction between the chip and tool interface. Although liquid nitrogen as an environmentally safe coolant has been widely recognized in cryogenic machining, its function as a lubricant is plausible due to its chemical inertness, physical volatility and low viscosity. Since a reduced friction is a direct witness of the lubrication effect from a tribological viewpoint, this paper presents an evaluation of the apparent friction coefficient on the tool-chip interface in cryogenic cutting operations to prove and characterize the lubricity of LN2 in cryogenic machining. The mathematical approaches have been formulated to derive the normal and frictional forces on the tool-chip interface for the oblique cutting tests.

Keywords

References

  1. Uehara, K and Kumagai, S., Characteristics of Tool Wear in Cryogenic Machining, J. of Japan Society of Precision Engineers, Vol.35, No.9, 1969, pp.73-77
  2. Uehara, K and Kumagai, S., Chip Formation, Surface Roughness and Cutting Force in Cryogenic Machining, Annals of CIRP 17 (1), 1998, pp165-172
  3. Fillipi, A.D. and Ippolite, R., Facing Milling at -180OC , Annals 19 (2), 1971, pp 314-322
  4. Jainbajranglal, J.R. and Chattopadhyay, A.B, Role of Cryogenics in Metal Cutting Industry, Indian Journal of Cryogenics, Vol.0, No.1, 1984, pp.212-220
  5. Wang, Z.Y, Rajurkar, K.P. and Fan J., Turning Ti-6Al-4V with Cryogenic Cooling, Transactions of NAMRI/SME, Vol.24, 1996, pp.3-8
  6. Wang, Z.Y. and Rujurkar, K.P., Cryogenic Machining of Hard-to-cut Materials, Wear 239, 2000, pp.168-175
  7. Boothroyd, G. and Knight, W.A., Fundamentals of Machining and Machine Tools, Marcel Dekker Inc., 2nd edtion, 1989
  8. Trend, E.M., Metal Cutting, Butherworths Publication, London, 1984