Load-dependent wear transitions in thermally oxidized Ti-6Al-4V: A factorial stress-field-based structure-property-performance analysis
Tribology International, cilt.223, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 223
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.triboint.2026.112224
- Dergi Adı: Tribology International
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Chimica, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Factorial design, Hertzian stress containment, Thermal oxidation of Ti-6Al-4V alloy, Wear regime transition
- Bilecik Şeyh Edebali Üniversitesi Adresli: Evet
Özet
Thermal oxidation (TO) is an effective surface modification technique for enhancing the tribological performance of Ti-6Al-4V through the formation of a rutile oxide layer (OL) and an underlying oxygen diffusion zone (ODZ). However, previous studies have primarily attributed wear improvement to oxide thickness or surface hardness, while load-dependent transitions between oxide-controlled and substrate-involving wear have not been quantitatively addressed. In this study, two TO conditions (600 °C/60 h and 700 °C/30 h) were systematically investigated using a 36-condition full factorial design incorporating variations in applied load (1.875–15 N) and sliding speed (10–30 mm s−1) under reciprocating dry sliding against Al2O3. The mass-gain results were consistent with diffusion-controlled oxidation behavior reported for Ti alloys, producing OL thicknesses of approximately 1 µm and 5 µm, and mechanically effective ODZ depths of ∼30 µm and ∼45 µm for the 600 °C/60 h and 700 °C/30 h conditions, respectively. Statistical analysis identified the thermal process as the dominant factor governing wear rate, with its interaction with load controlling transitions between wear regimes. A dimensionless stress-field containment ratio based on Hertzian contact theory was introduced to compare the diffusion-hardened depth with subsurface shear stress penetration. The results demonstrate that wear behavior is governed by the relationship between hardened depth and stress-field distribution, indicating that TO produces load-dependent surface architectures rather than universally improved surfaces.