Double-Layer Light Metal Brake Drum

Shandong Zonxin Auto Parts Co., Ltd. developed and designed a double‑metal brake drum using ZL270LF aluminum alloy for the outer layer and aluminum‑ceramic material for the inner layer, employing a company‑invented double‑layer casting process—the world's first of its kind. The product is currently under development.

1) Material:
Outer layer: ZL270LF aluminum alloy (lightweight, high strength, corrosion‑resistant). Inner layer: aluminum‑ceramic (lightweight, wear‑resistant, high‑temperature resistant).

2) Structure:
Double‑layer structure combining the advantages of each material. External ribs/fins are designed for ventilation and cooling to reduce thermal cracking and lower brake shoe carbonization risk.

3) Process:
Double‑layer casting method (dual‑layer pour).

4) Assembly:
Due to differences in thermal expansion coefficients between aluminum alloy and steel parts, the assembly line is equipped with high‑precision displacement sensors with a reciprocating precision error ≤ 0.015 mm to improve service life.

5) Weight

Total vehicle weight savings for double‑layer light metal brake drums: 156 kg (based on a 13T three‑axle drum‑axle semi‑trailer).

6)Temperature Performance

Using double‑layer light metal brake drums, wheel end temperature rises by only ~30°C above ambient—significantly better than the ~60°C rise of traditional hubs—reducing wheel end temperatures by 50%. External rib/fan designs improve ventilation and cooling, mitigating thermal cracking and brake lining high‑temperature carbonization. This effectively eliminates wheel end fire risk.

7)Product Benefits:
Assuming a semi‑trailer transport cost of approximately RMB 0.35 per ton‑km, a daily driving distance of about 450 km, and an annual utilization of about 300 days, a three‑axle semi‑trailer equipped with double‑layer light metal brake drums can reduce vehicle weight by 156 kg per vehicle and achieve additional income of approximately RMB 5,000 per year.