Article 2026 · 0 atıf

Effects of Graphite Incorporation and Annealing on the Structural, Tribological, and Functional Properties of Electroless Ni-B Coatings

Bulbul, Ferhat, Kara, Adem, Bulbul, Leman Elif, Gunes, Kubra

Özet

This study explores the synergistic effects of graphite nanoparticles (0.1 wt.%) and thermal annealing (100-600 degrees C) on electroless Ni-B coatings for AISI 4140 steel. Graphite-enabled multifunctional performance-crystallization control, friction reduction, and antibacterial activity-are unlike conventional Ni-B systems. XRD showed amorphous-to-crystalline (Ni3B/Ni2B) transformation, with graphite acting as a nucleation agent below 300 degrees C before degrading at 600 degrees C. The 300 degrees C-annealed composite achieved optimal properties: 0.2 friction coefficient (75% lower than uncoated steel), 60% higher wear resistance, and hardness of 777 HV (+ 3.6% over as-deposited), attributed to graphite lubrication and nanocrystalline Ni3B formation. Antibacterial tests revealed a 3.4-mm inhibition zone against E. coli, though efficacy declined at higher temperatures due to graphite oxidation. All composites maintained superhydrophilicity (contact angle approximate to 0 degrees) without mechanical compromise. By correlating annealing temperature with microstructure, this work provides a design framework for Ni-B/graphite coatings combining low friction (mu = 0.2), high hardness (785 HV), and antibacterial functionality-addressing critical needs for wear-resistant, hygienic surfaces in biomedical and industrial applications.

Anahtar Kelimeler

W COATINGS P/NI-B NICKEL DEPOSITION BEHAVIOR WEAR ELECTRODEPOSITION HARDNESS

WoS Kategorileri

Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Mineralogy Mining & Mineral Processing

Künye

Dergi: JOM
Yıl: 2026
Cilt: 78
Sayı: 2
Sayfa: 1421-1446
ISSN: 1047-4838
eISSN: 1543-1851
DOI: 10.1007/s11837-025-07968-x
WoS UID: WOS:001616636100001

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