TiN/NbN nanoscale multilayer coatings deposited by High Power Impulse Magnetron Sputtering to protect medical grade CoCrMo alloys
Autor: | Imran Khan, Yashodhan Purandare, Papken Eh. Hovsepian, Arutiun P. Ehiasarian, Krishnanand Shukla, Arunprabhu Arunachalam Sugumaran |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
Materials science
Passivation Scanning electron microscope Wear coefficient fatigue resistance 02 engineering and technology engineering.material wear resistance 01 natural sciences Focused ion beam CoCrMo alloy fracture toughness Corrosion Coating 0103 physical sciences Materials Chemistry high power impulse magnetron sputtering (HIPIMS) Composite material 010302 applied physics Surfaces and Interfaces Sputter deposition Engineering (General). Civil engineering (General) 021001 nanoscience & nanotechnology Surfaces Coatings and Films TiN/NbN multilayer coating corrosion-resistant engineering TA1-2040 High-power impulse magnetron sputtering 0210 nano-technology |
Zdroj: | Coatings Volume 11 Issue 7 Coatings, Vol 11, Iss 867, p 867 (2021) |
ISSN: | 2079-6412 |
Popis: | This study describes the performance of nanoscale multilayer TiN/NbN coatings deposited on CoCrMo medical-grade alloys by utilising novel mixed high power impulse magnetron sputtering (HIPIMS) and direct current unbalanced magnetron sputtering (UBM) technique in an industrial size vacuum coater. Scanning electron microscopy analysis showed that these coatings were extremely dense without any intercolumnar voids. The coating exhibited high hardness of 28 GPa, as well as low friction and wear coefficient of 0.7 and 1.4 × 10−14 m3·N−1·m−1, respectively, as compared to the bare material. Scratch tests revealed superior coating to substrate adhesion due to the HIPIMS etching prior to coating deposition. Energy-dispersive X-ray analysis of the wear debris generated during the impact test together with focused ion beam cross-section analysis in different locations of the impact crater revealed the coating failure mechanism and further confirmed the excellent coating to substrate bonding strength. Potentiodynamic polarisation tests in NaCl and Hank’s solutions revealed the clear passivation behaviour, several orders of magnitude lower corrosion currents, and high pitting potentials of the coating, which guarantee excellent protection to the base alloy in such aggressive environments. Inductively coupled plasma mass spectrometry analysis of Hank’s solution containing corrosion debris of the coated sample revealed that the leaching of harmful metal ions from the base material was reduced to below the detection limit of the technique, thus demonstrating the high barrier properties of the coating. |
Databáze: | OpenAIRE |
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