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Acta Metall Sin  2026, Vol. 62 Issue (7): 1163-1174    DOI: 10.11900/0412.1961.2025.00409
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Research and Application Progress of SiCp-Reinforced Aluminum-Based Composite Brake Discs for Rail Transit Vehicles
TAN Dong1, WU Liukun2, FU Kangxi1, XIA Shaohua1, LI Chong2(), CUI Lei2, LIU Yongchang2, ZAN Yuning3
1 CRRC Qishuyan Institute Co. Ltd., Changzhou 213011, China
2 State Key Laboratory of High Performance Roll Materials and Composite Forming, School of Materials Science and Engineering, Tianjin University, Tianjin 300350, China
3 Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
Cite this article: 

TAN Dong, WU Liukun, FU Kangxi, XIA Shaohua, LI Chong, CUI Lei, LIU Yongchang, ZAN Yuning. Research and Application Progress of SiCp-Reinforced Aluminum-Based Composite Brake Discs for Rail Transit Vehicles. Acta Metall Sin, 2026, 62(7): 1163-1174.

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Abstract  

Driven by the “dual-carbon” strategy, the lightweighting of rail transit equipment has become a dominant industry trend. Among the key components, the brake disc—critical to the braking system—faces particularly stringent weight-reduction requirements. SiCp-reinforced aluminum-based composites (SiCp/Al), known for their low density, high thermal conductivity, and superior wear resistance, are now regarded as the prime candidate to replace conventional cast-iron discs. In recent years, SiCp/Al brake discs have been implemented in urban rail transit vehicles operating at 120 km/h. However, their high-temperature stability remains a technical challenge, and no breakthroughs have been achieved for operation on suburban railways at speed ≥ 140 km/h. This study systematically reviews the research progress and engineering applications of SiCp/Al brake discs in rail transit, focusing on its fabrication methods, core performance, in-service behavior, and evaluation standards. Future development directions are discussed to guide technological innovation and the industrial deployment of advanced rail transit equipment.
Key words:  aluminum-based composites      brake disc      rail transit      lightweighting     
Received:  16 December 2025     
ZTFLH:  TG146.2  
Fund: National Key Research and Development Program of China(2023YFB3710602);National Nat-ural Science Foundation of China(U24A2026)
Corresponding Authors:  LI Chong, professor, Tel: 13021398676, E-mail: lichongme@tju.edu.cn
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TAN Dong
WU Liukun
FU Kangxi
XIA Shaohua
LI Chong
CUI Lei
LIU Yongchang
ZAN Yuning

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https://www.ams.org.cn/EN/10.11900/0412.1961.2025.00409     OR     https://www.ams.org.cn/EN/Y2026/V62/I7/1163

Fig.1  Photos (a1, b1) and installation mode diagrams (a2, b2) of the wheel-mounted brake disc (a1, a2) and axle-mounted brake disc (b1, b2)
Fig.2  Schematic of the stir-casting apparatus[5] (a); photo (b) and OM image (c) of stir-cast aluminum-based composite brake disc
Fig.3  Flowchart of the powder-metallurgy process for fabricating aluminum-based composite brake discs[16]
Fig.4  Friction-stir forming equipment and schematic of process (inset)[18]
Fig.5  Photo (a) and OM image (b) of composite formed SiCp reinforced aluminum-based composite brake disc
MaterialUltimate tensile strength / MPaElongation / %Hardness / HBW
Stir-cast disc[16]~170~1.7~78
Powder-metallurgy disc[16]300-3502.0-4.0110-130
Composite formed disc200-3602.0-6.080-130
Table 1  Comparisons of mechanical properties (measured average values) of aluminum-based composite brake-disc body materials
Fig.6  Test equipment (a) and key components (b) of full-scale brake friction
Fig.7  Schematics showing the friction and wear mechanisms of brake discs with 20% (a) and 30% (b) SiCp particles[22]
Fig.8  Micro growing process model of the thermal fatigue crack[35]
(a) initial (b) crack initiation (c) crack broadening
(d) crack went through the matrix (e) sub crack at the front of main crack
(f) sub crack on the side of main crack
Brake disc typeEnergy consumption per brakingEnergy consumption per round tripDaily energy consumptionAnnual energy consumptionEnergy saved annually
Cast-iron1.012020278867-
Aluminum alloy0.388762946749400
Table 2  Traction energy consumption calculation for a Train's brake discs[39]
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