Aluminum matrix composite brake disc for subway and metro — unsprung-weight reduction where it matters.
Cutting 7.5 tonnes of unsprung weight per 8-car train lowers track wear, acceleration energy, and braking load.
Roughly 4× the conductivity of cast iron, so braking heat disperses fast — no thermal hot spots, no cracking.
Total cost over operating-time × year beats ductile cast iron despite a higher unit price.
Backed by a 300+ formulation database and multi-dimensional matching of powder + ceramic reinforcement.
Key metrics under matched operating conditions, sourced from Xiangtou thermal-mechanical simulation and bench tests.
| Metric | Cast iron | Al-matrix composite | Δ |
|---|---|---|---|
| Disc weight | 76 kg | 30 kg | −60% |
| Peak surface temp (T_max) | >342 ℃ | 305 ℃ | cooler |
| T_max ÷ T_min ratio | 3.42 | 1.55 | more uniform |
| Density | ~7.2 g/cm³ | 2.8–3.05 g/cm³ | −58% |
Cast iron brake discs on rail vehicles are heavy. Every kilogram of unsprung weight costs energy at every acceleration and every braking cycle. Traditional composite upgrades hit a wall on heat — the brake material either cracks under thermal cycling or loses stiffness at temperature.
Xiangtou’s powder-metallurgy aluminum matrix composite threads that needle. The matrix stays stiff hot. The ceramic reinforcement absorbs energy. And because conductivity is roughly four times cast iron, heat leaves the disc before it can pool into a crack-forming hot spot.
See full property envelopes on the Technology page.
XIANGTOU