Effect of Ceramic Reinforcement Type on Friction Stability and Wear Resistance of Cu and Cu-Bronze Matrix Powder Metallurgy Brake Composites
METALS, cilt.16, sa.9, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 16 Sayı: 9
- Basım Tarihi: 2026
- Doi Numarası: 10.3390/met16090985
- Dergi Adı: METALS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Compendex, INSPEC, Directory of Open Access Journals, Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Kocaeli Üniversitesi Adresli: Evet
Özet
The tribological performance of copper-matrix sintered brake pads for high-speed rail applications is strongly influenced by ceramic reinforcement type. However, a systematic comparison of SiC, ZrO2, and SiO2 within Cu and Cu-Bronze (Cu-Br) matrix systems remains limited. In this study, six powder metallurgy composites were produced by cold pressing and sintering at 900 degrees C, with each matrix reinforced with 2 wt.% SiC, ZrO2, or SiO2 and containing graphite and MoS2 as solid lubricants. Tribological tests were performed at 25, 100, and 400 degrees C under an 18 N normal load. Microstructural and thermal characteristics were evaluated using optical microscopy, SEM/EDS, and DTA/TGA. The coefficient of friction (COF) ranged from 0.163 to 0.364 across all formulations and temperatures. The Cu-Br-based composites exhibited a narrower reinforcement-dependent COF range than the Cu-based composites, particularly at elevated temperatures. Cu-SiO2 showed the highest COF within the Cu-based at all test temperatures, whereas Cu-Br-SiC composite exhibited the highest COF among the Cu-Br-based composites at 400 degrees C. The lowest specific wear rates were obtained for Cu-SiO2 at 25 degrees C and Cu-SiC at 400 degrees C. SiC-reinforced composites exhibited the highest hardness within both matrix systems.