Research Information System
Yavuz M. (Executive)
Project Supported by Higher Education Institutions, 2020 - 2020
Hard
turning is nowadays a widely used method in machining industries for machining
hardened steel. While this method offers high processing efficiency and green
environmental protection, it also enables the efficient use of energy. It is
possible to increase the strength of machine parts three times with heat
treatment. With heat treatment, the hardness value of the material increases
with increasing strength. Increased hardness value also increases tensile
strength, friction and wear resistance. Within the scope of this project, hard
turning of the material, whose mechanical and chemical properties have been
improved with the chroyogenic cooling method, has been investigated. Thus, it
is aimed to achieve optimum advantages of hard turning above with appropriate
process parameters. Mechanical and chemical properties of AISI 4140 material
were compared before and after cryogenic treatment. For this, firstly, the
hardness value of 60-65 HRC is given to the material. Then, chromyogenic
cooling was applied at -200 degrees for 12 hours. Later, this material was
reached to a hardness value of 55 HRC by applying a 2-hour tempering process at
250 degrees. Hard turning was performed with the material whose mechanical and
chemical properties were improved by cryogenic process. In the experiments, 3
different feed rates, 3 different cutting speeds and 3 different depths of cut
were used. At the end of the experiment, surface roughness, cutting force,
sound level and power consumption were evaluated. In this study, where more
than one performance criteria is evaluated, the Axiomatic Design method was
used for optimization. Finally, wear experiments were carried out to see the
effects of cryogenic process on tool wear.