Aluminum die casting is a high-pressure forming process that can produce high-precision, complex-shaped, and excellent-surface-quality die casting components suitable for mass production. On the other hand, aluminum sand casting uses a disposable sand mold, which provides greater design flexibility and can produce larger sand casting parts, but with a rougher surface. The choice of casting method depends on the order volume, budget, part complexity, and mechanical performance requirements.
This article will deeply examine the features, applications, materials, mechanical properties, costs, and surface treatments in aluminum die casting and sand casting. Read on to help you find the most suitable process for your next aluminum casting project.
Aluminum Die Casting
Overview
Aluminum die casting is a metal forming process that injects molten aluminum alloy into a metal mold at high speed under high pressure and obtains precision aluminum alloy parts after cooling and solidification.
Main Features
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High dimensional accuracy, tolerance up to ±0.05mm, reducing the need for subsequent machining.
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A high surface finish can be used after simple post-processing.
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Short production cycle, suitable for mass production, improving production efficiency.
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Can manufacture complex geometric shapes, suitable for thin-walled structures and high-precision parts.
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Permanent steel molds are used, which can be reused hundreds of thousands of cycles to reduce long-term production costs.
Common Applications
- Automotive: engine mounts, transmission cases, suspension knuckles, alloy wheels, brake calipers.
- Machinery: gearbox housings, pump impellers, hydraulic valve bodies, bearing brackets, connecting rods.
- Electronics: heat sinks, LED heat sinks, electronic enclosures, connector housings, motor brackets.
- Aerospace: aircraft engine housings, structural ribs, wing brackets, landing gear components, satellite frames.
- Home Appliances: refrigerator compressor housings, washing machine tubs, air conditioner frames, oven burner covers, vacuum cleaner handles.
Common Materials
Aluminum die casting usually uses high-flow and high-strength cast aluminum alloys, including:
- ADC12
- A380
- A360
- AlSi9Cu3
Mechanical Properties
The following data represents the mechanical properties of aluminum castings after die casting process:
|
Aluminum Alloy |
Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HB) |
|
ADC12 |
295 | 160 | 2 | 80 |
|
A380 |
310 | 160 | 3.5 |
80 |
| A360 | 320 | 175 | 2.5 |
75 |
| AlSi9Cu3 | 280 | 140 | 1 |
85 |
Production Cost Analysis
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Mold Cost: Uses high-strength steel molds with a high initial cost but a long lifespan (up to hundreds of thousands of cycles).
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Unit Cost: Lower unit cost, suitable for mass production.
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Post-Processing Cost: High precision and smooth surfaces often require minimal post-processing costs.
Surface Treatment Options
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Sandblasting: Removes minor imperfections and improves surface uniformity.
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Anodizing: Enhances corrosion resistance and provides a decorative finish.
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Electroplating (Chrome, Zinc): Improves wear resistance and conductivity.
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Powder Coating: Increases oxidation resistance, making it suitable for outdoor applications.
Aluminum Sand Casting
Overview
Aluminum sand casting is a process of pouring molten aluminum alloy into a mold made of sand and a binder, and then removing the sand mold to obtain aluminum alloy castings after it cools and solidifies.
Main Features
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Suitable for the production of large-sized sand casting parts weighing hundreds of kilograms or even tons.
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Sand molds are low-cost and suitable for small-batch production or customized parts manufacturing.
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Allows the design of complex internal channels and hollow structures for special applications.
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Can manufacture parts with thicker walls without being limited by mold strength.
Common Applications
- Automotive: engine blocks, cylinder heads, transmission cases, differential housings, suspension components.
- Aerospace: aircraft engine mounts, landing gear components, structural fittings, wing ribs, satellite structural components.
- Machinery: pump casings, hydraulic valve bodies, gearbox housings, bearing supports, industrial tooling components.
- Energy: turbine housings, generator casings, heat exchanger tubesheets, pipeline fittings, solar panel frames.
Common Materials
Aluminum sand casting usually uses aluminum alloys with good castability, high strength, and heat resistance, including:
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A356
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A319
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A206
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C355
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A535
Mechanical Properties
The following data represents the mechanical properties of aluminum castings after sand casting process:
|
Alloy Grade |
Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HB) |
|
A356 |
228 | 160 | 3 | 60 |
|
A319 |
241 | 172 | 1 | 75 |
| A206 | 310 | 275 | 6 |
120 |
| C355 | 265 | 210 | 3 |
95 |
| A535 | 255 | 170 | 10 |
70 |
Production Cost Analysis
- Mold Cost: Uses disposable sand molds that must be recreated for each casting, resulting in lower mold costs but higher recurring setup expenses.
- Unit Cost: Higher unit costs due to manual mold creation and longer cycle times.
- Post-Processing Cost: Sand Casting: Rougher surfaces require additional post-machining, grinding, and polishing, increasing overall expenses.
Surface Treatment Options
- Mechanical Polishing: Reduces roughness and improves surface finish.
- Painting & Coating: Provides protective layers for corrosion resistance.
- Chemical Oxidation: Enhances heat resistance and minimizes oxidation risks.
CEX’s Professional Aluminum Die Casting Services
CEX is an industry leader in aluminum die casting, providing tailored one-stop solutions for each of your projects.
Why Choose Us
Mold Service
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In-house mold design and manufacturing saves time and budget.
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Mold flow analysis service predicts potential die casting defects.
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Regularly maintain and retool the molds, the customer only needs to bear the cost of the first set of molds.
Our Equipment
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Raw Material Centralized Melting: Can discharge excess impurities and gases to improve raw material purity.
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160T–1100T Die Casting Machines: Can produce parts with a weight range of 10g-20kg, wall thickness of 2mm-15mm, and part size up to 1.2m x 0.8m.
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Optimized Feeding and Cooling Systems: Can reduce die casting defects such as shrinkage, porosity, cold shut, and cracks.
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Robotic Arms: Fully automatic material loading and unloading improves production efficiency.
Quality Inspection Instruments
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Alloy Composition: spectrometer.
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External Dimension: CMM, caliper.
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Internal Structure: X-ray machine. We conduct X-ray inspections during production to monitor product quality at any time.
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Mechanical Properties: tensile tester, hardness tester.
Conclusion
Aluminum die casting and aluminum sand casting are each suitable for different manufacturing needs.
Aluminum die casting components are ideal for the high-volume production of high-precision, complex castings, while aluminum sand casting parts are suitable for large-size, low-volume parts.
Choosing the right casting method depends on factors such as order volume, budget, part complexity, and mechanical performance requirements.
As a professional aluminum die casting manufacturer with more than 29 years of industry experience and more than 10 years of export experience, CEX is committed to providing end-to-end turnkey services for your project.
Contact us today to find out how we can turn your next project from concept to reality.