Tribological Performance Analysis of Castor–Black Cumin Hybrid Oil Doped with Boron Nitride in Cold Rolling


ÖZAKIN B., Gültekin K., Uymaz S. E.

Applied Sciences (Switzerland), cilt.16, sa.14, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 16 Sayı: 14
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3390/app16146932
  • Dergi Adı: Applied Sciences (Switzerland)
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Compendex, INSPEC, Directory of Open Access Journals
  • Anahtar Kelimeler: black cumin oil, castor oil, hexagonal boron nitride (h-BN), material ratio curve, optical profilometer, surface roughness
  • Ondokuz Mayıs Üniversitesi Adresli: Evet

Özet

In this study, the tribological performance of an environmentally friendly, high-performance castor oil–black cumin oil blend was investigated by adding hexagonal boron nitride (h-BN) nanoparticles at varying concentrations during cold rolling. Castor oil served as the base oil, and h-BN nanoparticles were incorporated at concentrations of 0.05%, 0.125%, and 0.25 wt.% into the system, which was optimized with 10 mg/mL of black cumin oil. Performance was evaluated on steel specimens at 5% and 20% reduction ratios. The results demonstrated that, compared to undoped castor oil under dry conditions, the rolling force was reduced by approximately 18% and 9% at 5% and 20% reduction ratios, respectively. The best performance was achieved with the hybrid lubricant containing 0.25 wt% h-BN. Under these conditions, surface roughness parameters reached their lowest values at a 20% reduction ratio; specifically, reductions of approximately 23%, 17%, and 21% were observed in Ra, Rp, and Rv, respectively, compared to undoped castor oil. Furthermore, with the same formulation at a 5% reduction ratio, improvements of up to 17%, 21%, and 15% were achieved in the Sk, Spk, and Svk parameters, respectively. Optical and microscopic images revealed that h-BN nanoparticles formed a tribofilm that filled surface valleys and reduced contact between the roller and the workpiece.