Akademik Veri Yönetim Sistemi
1st International Conference on Advances in Engineering, Architecture, Science and Technology, Erzurum, Türkiye, 15 - 17 Aralık 2021
The corrosion property of a material is one of the main subjects studied within the scope
of surface engineering. When the literature is examined, it is seen that electrochemical
methods are frequently used in the determination of corrosion properties. It offers very
fast and accurate results, especially in the analysis of materials with improved corrosive
properties by surface modifications. One of the most important modules of this method
is potentiodynamic polarization experiments. This method, which provides information
about the corrosion rate and amount of the material surface, gives very sensitive results
with computer integrated package programs. The right selection of predetermined test
parameters increases the degree of this sensitivity. In the potentiodynamic polarization
experiment, the values entered into the system are respectively; scan rate, potential range,
sample surface area, material density and equivalent weight. In this study, the effect of
different scan rates on the measurement accuracy was investigated. Using two different
parameters on the same base material (AISI 4140 steel), four different scan rates were
applied (0.25 mVs-1
, 0.5 mVs-1
, 0.75 mVs-1
, 1 mVs-1
) for three different morphologies
with the untreated surface. The plasma nitriding process was used as the surface
modification technique. By using two different parameters, 400°C - 1 hour and 500°C -
4 hours, different surfaces with different layer thicknesses were obtained. Thus, the layer
thickness and corrosion behavior of diffusional coatings were associated with the scan
rate. 3.5% NaCl was used as the electrolyte. In the triple galvanic cell arrangement, the
reference electrode is Ag/AgCl and the counter electrode is graphite. Polarization values
were chosen between -0.5 mV and +1.5 mV. Before the potentiodynamic polarization
measurements, the open circuit potential of each condition was monitoring for 3600
seconds. The anodic and cathodic arms of the obtained potentiodynamic polarization
curves were examined in terms of quality and quantity. The effect of different scan rates
on the result parameters obtained after the experiment was interpreted