MEASUREMENT OF CUTTING TEMPERATURE AND EMISSION PROPERTIES OF STEEL.

It has been found previously that the accuracy of measurements of temperature with natural thermocouples increases if calibration is carried out using the machined material hardened during plastic deformation, i. e. , the roots of shavings; this is caused by the fact that hardening and the 'juvenile' nature of the contact layers and the area and transition resistance of the contact should correspond to the real cutting process. Hardening of medium-carbon steel proportional to the microhardness of the roots of the shavings (chips) reduces the thermal emf of the steel-hard alloy pair in calibration by 10% and more. The author analyzes the relationship of the microstructure and hardness of the steel, with its emission properties determining the accuracy of measurement of temperature using the natural thermocouple. He finds that: (1) The relationship of the emission and strength properties of the steel is invariant to contact interaction in machining. (2) The measurement of cutting temperature based on the emission properties of the steel should be carried out taking into account the dynamics of contact interaction and by the differential method. (3) The range of application of the chip roots as the method of analysis should be restricted to exmaination of the inertia aspects of cutting metals.