Temperature effects cutting tools

These combined effects raise the temperature of the tool, workpiece and chip to a level that would be unacceptable in most operations if it were not for the presence of cutting fluid. Since the cooling effect is the greatest benefit, cutting fluids are widely known as coolants . In... 

Similar problems arise with many metal working fluids. These are sprayed onto the cutting tools, fall into an open collecting vessel, and are recirculated. They are frequently contaminated with organic detritus such as food crumbs, and mice or rat faeces or urine. They may be topped up periodically with fresh oil and maintained at temperatures of 20-30 °C leading to rapid deterioration. The effect of bacterial metabolism is to break the emulsion into organic and aqueous layers, the oil is converted into fatty acids, the pH falls the emulsion becomes useless and may cause corrosion spots on the finished item. 

Ueda T, Hosokawa A, Yamada K (2006) Effect of oil mist on tool temperature in cutting. ASME, J Manuf Sci Eng 128(2) 130-135... 

Increasing the relative speed between the tool and the workpiece causes a combined increase in temperatures and temperature gradients on the cutting tool and in the chip, decreasing specific forces and reduced subsurface effects on the workpiece (Fig. 15) (Tonshoff et al. 2005b Neugebauer et al. 2011). 

Ng used Abaqus/Explicit to simulate an orthogonal cutting process to model high-speed face milling. He developed two FE models to assist in explaining the effects of tool wear on the temperature and shear stress distribution in the workpiece material. The FE results correspond to experimental observations (Ng et al. 2004). 

Oil mist is very effective in the cutting performance of a rotary cutting tool. The influence of oil mist on tool temperature is shown in Figs. 10 and 11. Ordinary biodegradable oil mist is supplied with 30 cc/h. The tool temperature decreases approximately 50° by the cooling effect of the oil mist. 

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