Aluminum Titanate Sprue Bushing is an Al₂TiO₅ ceramic component installed between the riser tube and the down mould in low-pressure aluminum casting machines. It guides molten aluminum into the mold cavity while maintaining stable flow, thermal insulation, and dimensional stability under repeated thermal cycling.
Key Features of Aluminum Titanate Sprue Bushing
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Low thermal expansion for stable sealing
Aluminum titanate shows a linear thermal expansion coefficient typically below 1.5 × 10⁻⁶ / °C between room temperature and 1000 °C, reducing stress at the metal-to-ceramic interfaces in the sprue area. -
High thermal shock resistance for repeated casting cycles
Microcracked Al₂TiO₅ ceramics combine low CTE and low thermal conductivity, allowing sprue bushings to withstand rapid heating and cooling cycles in low-pressure casting without cracking. -
Non-wetting behavior with molten aluminum
The aluminum titanate surface is not easily wetted by molten non-ferrous metals, which limits build-up, reduces inclusion risk, and simplifies maintenance inside the gating system. -
Controlled apparent porosity and stable mechanical strength
Typical apparent porosity below about 7–8 % and flexural strength in the 25–35 MPa range provide a good balance between thermal insulation and structural integrity in the sprue region. -
Service temperature suitable for aluminum alloys
Aluminum titanate sprue bushings are designed for continuous work around 1000 °C with short-term excursions above this range, matching the molten aluminum temperature window while limiting thermal damage.
Aluminum Titanate Ceramic Sprue Bushing Properties
| Parameter | Typical Value | Description |
| Coefficient of Thermal Expansion (CTE) | 0.5–1.5 ×10⁻⁶ /K | Extremely low expansion that maintains dimensional stability under molten aluminum temperatures. |
| Thermal Shock Resistance | Very high | Withstands rapid temperature fluctuations without cracking during casting cycles. |
| Density | 2.8–3.0 g/cm³ | Medium-density ceramic structure suitable for molten aluminum system components. |
| Thermal Conductivity | 1.5–3.0 W/m·K | Helps reduce heat loss along riser tubes, spouts and transfer components. |
| Maximum Service Temperature | 900–1100°C | Suitable for typical molten-aluminum environments and transfer systems. |
| Flexural Strength (MOR) | 10–25 MPa | Provides sufficient strength for handling, installation and operational load. |
| Elastic Modulus | 20–40 GPa | Lower stiffness contributes to excellent thermal shock tolerance. |
| Porosity | 12–25% | Supports insulation and limits internal thermal stress accumulation. |
| Chemical Compatibility | Non-wetting to molten aluminum | Prevents adhesion, oxide buildup and contamination in casting processes. |
| Dimensional Stability | Stable through long cycles | Maintains geometry during prolonged molten-aluminum exposure and thermal cycling. |
Aluminum Titanate Ceramic Sprue Bushing Specifications
| Item No. | Diameter (mm) | Thickness (mm) | Purity |
| AT-TSL-JK1001 | Customize | ||
Aluminium Titanate Sprue Bushing Packaging
- Each sprue bushing is wrapped in shock-absorbing soft material to protect edges and sealing faces from impact.







