Agata Sotniczuk

Bio: Agata Sotniczuk is an academic researcher from Warsaw University of Technology. The author has contributed to research in topics: Corrosion & Titanium. The author has an hindex of 6, co-authored 12 publications receiving 81 citations.

Corrosion behavior of titanium modified by direct laser interference lithography

Abstract: This paper reports on the corrosion behavior of Titanium Grade 2 when subjected to non-contact laser functionalization. Direct Laser Interference Lithography (DLIL) was used to create periodic topography with two different surface patterns on pre-modified titanium. Corrosion resistance was measured in physiological saline at 37 °C. Electrochemical Impedance Spectroscopy data (EIS) and potentiodynamic polarization curves were correlated with the characteristics of the passive films through analysis of the topography, chemical composition, and thickness of oxides formed on the titanium after surface modifications. The corrosion tests showed that laser-textured surfaces have a beneficial impact on titanium corrosion resistance in a physiological saline solution 0.9% NaCl. Moreover, the passive layer on DLIL-modified samples is more stable and less susceptible to growth in the corrosive environment. The results highlight the local interaction of DLIL treatment of the titanium surface after it had been shot-peened and acid-etched. The improved corrosion resistance in DLIL samples derives mainly from changes in the surface topography, chemical composition, and thickness of oxide films obtained after laser processing.

Microstructure and mechanical properties of titanium subjected to direct laser interference lithography

Abstract: This study concerns a detailed cross-section microstructural analysis conducted by combining complementary methods such as FIB, SEM, EDS and STEM on different scales in order to elucidate the impact of direct laser interference lithography on the microstructure and surface chemistry of a Ti substrate after laser patterning. Special attention was paid to correlate the mechanical properties determined by the nanoindentation tests with the microstructure and phase composition analysed using GI-XRD. Direct laser interference lithography surface texturing results in the formation of a thin (1–1.5 μm), continuous layer with lath-like grains. The GI-XRD analysis showed no changes in phase composition, which is in agreement with our previous results. Furthermore, laser patterning led to an increase in the nano-hardness of the surface (from 2.8 GPa to 6.6 GPa) that is mainly related to the changes that took place in the microstructure. The results presented are important to an evaluation of laser-patterned surfaces in biomedical applications, as their ultimate use depends not only on topographical changes but also mechanical properties variations as well as microstructure evolution which affects its electrochemical properties.

Influence of grain refinement on the corrosion behavior of metallic materials: A review

Abstract: Grain refinement can strengthen the mechanical properties of materials according to the classical Hall-Petch relationship but does not always result in better corrosion resistance. During the past few decades, various techniques have been dedicated to refining grain, along with relevant studies on corrosion behavior, including general corrosion, pitting corrosion, and stress corrosion cracking. However, the fundamental consensus on how grain size influences corrosion behavior has not been reached. This paper reviews existing literature on the beneficial and detrimental effects of grain refinement on corrosion behavior. Moreover, the effects of microstructural changes (i.e., grain boundary, dislocation, texture, residual stress, impurities, and second phase) resulting from grain refinement on corrosion behavior are discussed. The grain refinement not only has an impact on the corrosion performance, but also results in microstructural changes that have a non-negligible effect on corrosion behavior or even outweigh that of grain refinement. Grain size is not the only factor affecting the corrosion behavior of metallic materials; thus, the overall influence of microstructures on corrosion behavior should be understood.