• Hassel, Achim Walter
• Lone, Shaukat Ali
• Mardare, Andrei Ionut
• Mardare, Cezarina Cela

Abstract

<jats:p>High throughput combinatorial analysis is a cost effective and time saving approach for characterizing a wide range of alloys. This technique can be used to optimize the chemical composition for several applications i.e. corrosion resistance and pharmaceutical<jats:sup>[1-2]</jats:sup>. Austenitic stainless-steel (AISI 316L and ASTM F-55) exhibits excellent load bearing and tribocorrosion resistance in human body condition<jats:sup>[3]</jats:sup>. However, these alloys have shown ineffectiveness to resist the localized form of corrosion and harmful release of metallic ions i.e. Ni, Cr and Fe in the human body<jats:sup>[4]</jats:sup>.</jats:p><jats:p>Hereby a ternary library with a compositional matrix of Fe (59-86 at.%), Ni (3-15 at.%) and Cr (9-30 at.%) is produced through co-sputtering. All compositions exhibited a columnar grain structure with pointy tips. The grain size ranged between 10-50 nm. Broad peaks corresponding to respective (110) and (211) planes of rt Fe (BCC) were detected in XRD patterns. These peaks were tentatively assigned to the solid solution of Fe with Cr and Ni. All electrochemical experiments were undertaken in Ringer’s solution at 37 <jats:sup>o</jats:sup>C by means of an in house-built flow type scanning droplet cell microscope. Additionally, the used electrolyte was analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). It was observed that as the Fe concentration increases more than 82 at.%, the preferential dissolution of Fe occurred continuously during cyclic voltammetry experiments. Simultaneously, Cr exhibited a surface enrichment (non-congruent dissolution) at all concentrations, but a minimum of (14-16 at.%) is required to behold the significant passivity. Interestingly, no metal was detected above detection limit during cyclic voltammetry for the alloys with compositions containing Ni &gt; 11 at.% and Cr &gt; 20 at.%. This work shows the influence of each constituent (Fe, Ni and Cr) on the passivity of Fe-Cr-Ni ternary system. Hence, it can also be perceived as a guideline for the surge of better performing Fe-Cr-Ni ternary alloys as a biomedical implant.</jats:p><jats:p>References</jats:p><jats:p>[1] Natalia Pimenova and Thomas Starr, Electrochemical Corrosion Investigation of 49-Cell Combinatorial Library of Titanium-Based Alloys Fabricated by DMD, <jats:italic>J. Electrochem. Soc</jats:italic>, 155, 303-305, (2008); DOI: 10.1149/1.2899021.</jats:p><jats:p>[2] John Murphy, Tetsuo Uno, Janice Hamer, Fred Cohen, Varavani Dwarki, Ronald Zuckermann, A combinatorial approach to the discovery of efficient cationic peptoid reagents for gene delivery, <jats:italic>PNAS</jats:italic>, 95, 1517-1522, (1998); DOI:10.1073/PNAS.95.4.1517</jats:p><jats:p>[3] M. Sumita, Y. Ikada, T. Tateishi, Metallic Biomaterials Fundamentals and Applications, <jats:italic>ICP</jats:italic>, Tokyo, 629 (2000).</jats:p><jats:p>[4] M. Sumita, Present status and future trend of metallic materials used in orthopedics, <jats:italic>Orthop. Surg</jats:italic>, 48, 927 (1997).</jats:p>

Topics

• impedance spectroscopy
• surface
• grain
• corrosion
• grain size
• x-ray diffraction
• experiment
• thin film
• steel
• chemical composition
• titanium
• biomaterials
• cyclic voltammetry
• atomic emission spectroscopy