{'fraction_non_alphanumeric': 0.02034058656575213, 'fraction_numerical': 0.009933774834437087, 'mean_word_length': 5.257396449704142, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
STUDY OF THE EFFECT OF TECHNOLOGICAL MILLING CONDITIONS ON THE QUALITY OF POLYMERIC MATERIALS FOR SENSITIVE ELEMENTS OF RADIATION CONTROL

The safety and reliability of the protection of ionizing radiation objects by the special units of the National Guard of Ukraine is determined by the quality of the devices for dosimetric control. Sensitive elements of modern dosimeters are made of thermoplastic polymers by mechanical milling. The properties of the polymer surface layer can be significantly changed during the process of thermophysical interaction with the cutting tool. As a result, the sensitive materials are losing the functional properties farther. The research work is devoted to determining the influence of technological conditions of production (geometry and material of the cutting tool, the parameters of the cutting mode) on the thermophysical state of the milled polystyrene (PS) surface layer. The presented results of thermographic studies of the milling process showed the increase in the maximum temperature at the cutting surface (from 55 °C till 70 °C) and changing the heterogeneity of the heat distribution (from 65,3% till 35,7%) with the growing of the cutting depth from 0,1 mm to 0,5 mm. The evaluation of quality of the formed surface layer was performed by thermodynamic characteristics (enthalpy, glass transition temperature) using method of differential scanning calorimetry. The detected changes in the properties of the PS testify the accumulation of deformation energy in the structure of the surface layer material. Under the conditions of satisfactory surface roughness, in all investigated modes, the process of relaxation of internal stresses in time and under the action of radiation is unpredictable. The most energetically stable condition of the PS is ensured with using a carbide cutting tool and cutting mode parameters v = 30 m/min, S = 0,05 mm/rev, t ≤ 0,1 mm. The established features of the PS should be considered by determining the technological parameters of the milling processes and evaluation of the quality of produced sensitive elements of dosimeters.