Article 9419

Title of the article

IMPROVING THE QUALITY OF THE SURFACE LAYER FOR THE MACHINING OF RESTORED PARTS OF TRANSPORT MACHINES 

Authors

Kurnosov Nikolay Efimovich, Doctor of engineering sciences, professor, sub-department of transport machines, Penza State University (40 Krasnaya street, Penza, Russia), E-mail: TTMO-PGU@mail.ru
Zakharov Yuriy Al'bertovich, Candidate of engineering sciences, associate professor, head of sub-department of road transport operation, Penza State University of Architecture and Construction (28 Germana Titova street, Penza, Russia), E-mail: avto@pguas.ru
Nikolotov Andrey Aleksandrovich, Senior lecturer, sub-department of transport machines, Penza State University (40 Krasnaya street, Penza, Russia), E-mail: Nikolotov@mail.ru 

Index UDK

621.91+621.85 

DOI

10.21685/2072-3059-2019-4-9 

Abstract

Background. The formation and structure of the surface layer, the characteristics of which depend on the processes occurring during processing, have a great influence on the operational properties of the restored car parts. When processing parts restored by the method of electric arc surfacing under a flux layer, one of the main indicators of the operational properties of the surface layer is microhardness, which is a consequence of the thermal processes occurring in the surface layer of the part. The nature of thermal and power phenomena during blade cutting is greatly influenced by the method of cooling the cutting zone. The influence of various methods of cooling the cutting zone on thermal processes and on the properties of the surface layer is not well understood. The aim of the work is to identify the effect of the cooling method on the microhardness of the surface layer of the parts restored after surfacing after processing.
Materials and methods. Investigations of temperature processes in the cutting zone were carried out by obtaining a picture of thermal fields with a NEC G120 thermal imager and analysis using special Thermography Studio software. The physicomechanical characteristics of the surface layer were evaluated by the method of microhardness measurement.
Results. The effect of the cooling method on the depth of the hardened layer is revealed. The regularity of the distribution of microhardness over the depth of the surface layer after blade processing with various cooling methods is determined. The temperatures of the cutting zone in the process of blade processing of the parts restored by surfacing were determined while cooling the cutting zone in various ways.
Conclusions. Cooling by aerosol water-oiled technological fluids allows more efficient cooling of the cutting zone (as compared with irrigation feed) during blade cutting of parts restored by surfacing. It was revealed that the cooling method does not have a significant effect on the depth of the hardened layer. The method of supplying cooling media affects the nature of the distribution of microhardness along the depth of the deformed layer. 

Key words

manufacture, micro hardness, hardening, cutting temperature, lubricating and cooling agents, aerosol, surfacing, repair, restoration, transport machines 

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References

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Дата создания: 12.03.2020 09:59
Дата обновления: 12.03.2020 11:00