Gravity Die Casting Manufacturer
Precision Casting – Achieve excellent dimensional accuracy and smooth surface finish for reliable parts.
Low Defects – Minimize porosity and shrinkage for zero-rework production.
Cost-Efficient – Ideal for medium-to-high volume production with lower per-unit cost.
Versatile Materials – Supports aluminum and zinc alloys for various components.
- Energy-Efficient – Gravity-driven process reduces energy use and mold wear.
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Your Reliable Gravity Die Casting Supplier in China
Solving Your Medium-to-Large Component Casting Challenges with Strength and Reliability
IEC Mould specializes in gravity die casting (GDC) for medium-to-large aluminum components used in automotive, aerospace, industrial machinery, and energy applications. Our in-house capabilities cover the full production chain — from DFM and mold design to casting, CNC machining, surface finishing, and assembly — ensuring complete process control and consistent quality. With our optimized Gravity Die Casting process, you benefit from:
- High structural integrity – Produce dense, defect-minimized components with excellent mechanical strength for demanding applications.
- Stable dimensional accuracy – Achieve tight tolerances for reliable fit, assembly, and interchangeability.
- Reduced porosity and shrinkage – Controlled gravity filling minimizes internal defects, lowering the need for rework.
- Cost-effective production – Ideal for medium-to-high volume runs with lower tooling wear and energy use.
Our advanced GDC equipment and ISO-certified quality control guarantee repeatable results for every project — from sturdy housings to functional structural components.
Partner with IEC Mould to simplify your supply chain, reduce production risks, and receive gravity die castings that meet your exact specifications — delivered reliably, every time.


















What is Gravity Die Casting?
Gravity Die Casting (GDC) is a permanent mold casting process in which molten metal is poured into a reusable steel or iron mold under the force of gravity, without the use of external pressure. The controlled filling and solidification create castings with excellent density, mechanical strength, and dimensional consistency.
Unlike High Pressure Die Casting (HPDC), which uses fast injection at extremely high pressure, GDC relies on a slower, more natural filling process. This minimizes turbulence during mold filling, significantly reducing porosity, shrinkage, and internal defects. The result is structurally sound castings with improved reliability for critical applications.
Gravity Die Casting is particularly well-suited for aluminum alloys and is commonly applied to medium-to-large components such as housings, brackets, engine parts, and heavy-duty industrial equipment. It offers a balance of mechanical performance, dimensional accuracy, and cost efficiency, making it ideal for applications where both strength and consistency are essential.
Because of its ability to deliver dense, defect-minimized castings with excellent repeatability, GDC is widely used in the automotive, aerospace, energy, and industrial machinery sectors, where safety, durability, and long service life are key requirements.
Why Choose Gravity Die Casting?
🧠 Engineers
Reliable dimensional accuracy for medium-to-large aluminum parts
Strong mechanical properties from dense, gravity-fed solidification
Suitable for structural components, housings, and heat-resistant parts
🕵️ Quality Control (QC) Professionals
- Low porosity and shrinkage through controlled metal flow
- ISO-certified inspection: CMM, X-ray, spectrometry, tensile testing
- Long mold life ensures consistent repeatability over production runs
💼 Procurement Teams
Cost-efficient for medium-to-high volume production
Lower tooling cost compared to high-pressure processes
Full-service supply chain support: mold design, casting, machining, finishing, and assembly
How Gravity Die Casting Works?
Gravity Die Casting (GDC) is a permanent mold casting process in which molten metal is poured into a reusable steel or iron mold under the force of gravity, rather than being injected under high pressure. This controlled filling method results in dense, mechanically strong castings with low porosity — making GDC ideal for medium-to-large aluminum components that require durability and dimensional reliability. Here is a step-by-step breakdown of how Gravity Die Casting works:
Step 1. Mold Preparation and Preheating
- Clean and preheat the permanent steel or iron die to around 200–300°C.
- Preheating reduces thermal shock, prevents premature wear, and ensures smooth metal flow.
- A refractory coating is applied to improve mold release and extend mold life.

Step 2: Molten Metal Preparation
- Aluminum (or other non-ferrous alloys) is melted in a holding furnace.
- Temperature is carefully controlled to maintain fluidity while avoiding oxidation.
- Degassing and refining may be applied to reduce inclusions and hydrogen porosity.

Step 3: Pouring into the Mold
- Molten metal is poured directly into the mold cavity using gravity, without external pressure.
- Controlled pouring minimizes turbulence and reduces the risk of oxide films and air entrapment.
- Runners and risers are designed to ensure complete cavity filling.

Step 4: Controlled Filling & Solidification
- The cavity fills gradually, allowing uniform distribution of molten metal.
- Slow, steady filling reduces shrinkage and internal voids.
- Faster cooling compared to sand casting leads to denser grain structure and improved strength.

Step 5: Cooling and Solidification
- The casting is allowed to cool naturally inside the permanent mold.
- Mold material extracts heat efficiently, resulting in better dimensional accuracy than sand casting.
- Proper cooling control ensures consistent mechanical properties and minimizes defects.

Step 6. Mold Opening & Casting Removal
- Once solidified, the mold is opened, and the casting is removed manually or with ejector pins.
- The permanent mold is then cleaned and prepared for the next cycle.

Step 7. Trimming & Flash Removal
- Runners, risers, and excess material are removed.
- Castings typically achieve near-net shape, minimizing the need for heavy machining.

Step 8. CNC Machining, Finishing & Inspection
- ritical surfaces may be CNC machined for precision.
- Surface treatments such as shot blasting, powder coating, or anodizing can be applied.
- Final inspection includes CMM measurement, X-ray, and mechanical property testing to ensure compliance with specifications.

Key Advantages of Gravity Die Casting
Advantage | For Engineers | For Procurement Teams | For Quality Control (QC) |
---|---|---|---|
Complex Geometry Capability | Enables casting of intricate shapes with multiple slides forming undercuts and fine details. | Eliminates costly secondary machining and assembly operations. | Reduces defect risk in complex parts thanks to precise die movement. |
Ultra-Fast Cycle Times | Achieves production rates of up to 20–25 cycles/min for small precision parts. | Increases throughput and lowers cost per part. | Faster cycles allow more frequent sampling for consistent QC checks. |
Tight Dimensional Tolerances (±0.02–0.05 mm) | Supports micro-scale precision designs for electronic, automotive, and medical components. | Reduces finishing and rework costs, ensuring parts are production-ready. | Improves repeatability and inspection efficiency for high-precision parts. |
Excellent Surface Finish (Ra 1.0–2.5 μm) | Produces smooth, cosmetic-grade finishes suitable for visible parts. | Cuts down polishing and finishing time, reducing total cost. | Easier detection of micro-defects during visual and dimensional inspections. |
Material Efficiency | Optimized gating system reduces scrap and minimizes re-melting. | Lowers raw material costs and improves yield. | Ensures uniform part quality with less variation across batches. |
Compact Machine Design | Multi-slide machines have smaller footprints compared to traditional die casting setups. | Reduces facility investment and simplifies integration into existing lines. | Shortens inspection logistics with parts produced closer to finishing stations. |
Thin-Wall & Lightweight Components | Allows manufacturing of durable thin-wall parts with high strength-to-weight ratio. | Reduces shipping costs and supports lightweight product design trends. | QC teams can consistently verify thin-wall accuracy with reduced failure rates. |
Ideal for High-Volume Small Parts | Economical for millions of precision components like connectors, gears, housings. | Low per-unit cost at scale, perfect for electronics and automotive supply chains. | Stable quality control across long production runs with minimal variation. |
Gravity Die Casting vs Other Casting Methods
✅ Gravity Die Casting (GDC) is a versatile casting process that uses gravity (without high-pressure injection) to fill reusable metal molds. It provides better mechanical properties and dimensional accuracy than sand casting, while being more cost-effective than high-pressure die casting for medium-volume production. GDC is widely used in automotive, aerospace, and industrial machinery for producing medium-to-large parts with good strength and durability.
Feature | Gravity Die Casting (GDC) | Hot Chamber Die Casting (HCDC) | Cold Chamber Die Casting (CCDC) | Sand Casting |
---|---|---|---|---|
Suitable Alloys | ✅ Most non-ferrous alloys (Al, Mg, Cu, Brass) | ✅ Low-melting alloys (Zn, Mg, Pb) | ✅ High-melting alloys (Al, Cu, Brass) | ✅ Most metals |
Filling Pressure | Gravity only (0 bar) | High (up to 1000+ bar) | High (up to 1500+ bar) | Gravity only |
Porosity | ⚠️ Moderate (lower than sand) | ⚠️ Moderate | ⚠️ Moderate | ❌ High |
Heat Treatment | ✅ Yes (T5/T6 common for Al alloys) | ❌ Often not applicable | ✅ T5/T6 Possible | ✅ Yes |
Surface Finish | ⭐⭐⭐ (Ra 3.2–6.3 μm) | ⭐⭐⭐⭐ (Ra 1.6–3.2 μm) | ⭐⭐⭐⭐ | ⭐ |
Dimensional Accuracy | ⭐⭐⭐ (±0.2–0.5 mm) | ⭐⭐⭐⭐ (±0.05–0.1 mm) | ⭐⭐⭐⭐ (±0.1 mm) | ⭐ |
Part Size Capability | Medium to Large | Small to Medium | Medium to Large | Large |
Ideal for | Medium-volume structural parts, wheels, brackets, manifolds | Small, intricate, high-volume parts | Structural housings, engine components | Large, simple prototypes or low-volume production |
Gravity Die Casting Part Applications Across Industries
Industry | Image | Typical Components | Why Gravity Die Casting Fits |
---|---|---|---|
Automotive & E-Mobility | Engine brackets, suspension arms, clutch housings, brake calipers, EV battery housings | Produces medium-to-large structural parts in aluminum or magnesium alloys with excellent strength, heat resistance, and fatigue performance. | |
Aerospace | Interior brackets, seat frames, hydraulic housings, engine components | Provides strong, lightweight, and heat-treatable components that meet strict aerospace quality and safety standards. | |
Industrial Machinery | Pump housings, gearboxes, compressor parts, machine tool components | Ensures durable, wear-resistant parts with good dimensional stability, suitable for heavy-duty applications. | |
Marine & Offshore | Propeller blades, engine covers, water pump housings, mounting brackets | Offers corrosion-resistant aluminum components capable of withstanding harsh saltwater environments. | |
Energy & Power Systems | Heat exchanger housings, turbine blades, motor housings, generator brackets | Produces strong and thermally efficient components for power generation and renewable energy equipment. | |
Household Appliances | Washing machine drums, motor housings, oven frames, refrigerator parts | Enables cost-effective production of durable aluminum components that can withstand long-term mechanical and thermal stress. | |
Construction & Hardware | Window frames, structural brackets, stair components, building connectors | Provides robust and heat-treatable parts with better durability than sand casting, ideal for structural applications. | |
Rail & Heavy Transport | ![]() | Brake system parts, coupling housings, structural brackets | Delivers high-strength components suitable for safety-critical and heavy-load applications in transport systems. |
Materials We Use for Gravotu Die Casting
Material | Key Features | Typical Applications | Why It Fits Gravity Die Casting |
---|---|---|---|
Aluminum Alloys (A356, A380, AlSi10Mg) | Lightweight, high strength-to-weight ratio, excellent corrosion resistance, good machinability, heat-treatable | Automotive wheels, engine blocks, cylinder heads, aerospace housings, structural parts | GDC allows controlled solidification for strong, defect-minimized aluminum parts suitable for structural and safety-critical applications |
Copper Alloys (Bronze, Brass) | High wear resistance, excellent thermal & electrical conductivity, good corrosion resistance | Plumbing fittings, marine components, electrical connectors, industrial bushings | Gravity filling supports dense, porosity-reduced copper alloy parts for conductive and wear-resistant uses |
Magnesium Alloys (AZ91, AM50) | Very lightweight, good damping capacity, moderate strength, good machinability | Aerospace housings, automotive lightweight frames, power tool casings | GDC provides reliable production of larger Mg alloy components where weight reduction is critical |
Zinc Alloys (ZA-12, ZA-27) | High strength, good toughness, excellent surface finish, cost-effective | Bearing housings, brackets, industrial machinery parts | GDC offers higher strength zinc castings compared to die casting, suitable for medium-size load-bearing parts |
Cast Iron (Grey Iron, Ductile Iron) | Very high strength, excellent wear resistance, vibration damping, cost-effective | Engine blocks, brake discs, machine bases, pipe fittings | Gravity pouring is suitable for high-mass castings with excellent mechanical strength |
Steel Alloys (Low-alloy, Stainless) | High toughness, excellent wear & corrosion resistance, high mechanical strength | Turbine housings, heavy-duty machinery parts, mining equipment | GDC molds withstand high temperatures, enabling complex medium-to-large steel castings |
Nickel & Specialty Alloys (Inconel, Monel) | Excellent high-temperature strength, corrosion resistance, oxidation resistance | Aerospace turbine blades, chemical plant valves, marine propellers | GDC enables controlled filling and solidification for complex, high-performance specialty alloy castings |
Common Technical Specifications – Gravity Die Casting (GDC)
- Filling Process:
Molten metal is poured by gravity from a ladle into a permanent (metal) mold, relying on gravity rather than high-pressure injection. Filling is slower and gentler, reducing turbulence and oxide formation. - Cycle Time:
Cycle times are typically 2–5 minutes, longer than pressure die casting, due to manual/semiautomatic pouring and controlled solidification. However, this slower cooling results in a finer grain structure and stronger mechanical properties. - Alloy Selection:
GDC is commonly used for aluminum alloys (A356, A380, AlSi10Mg), magnesium alloys (AZ91, AM50), copper alloys (bronze, brass), and occasionally cast iron or specialty steels. These alloys benefit from the controlled solidification offered by GDC. - Wall Thickness:
Typical wall thickness ranges from 3 mm to 12 mm. While not as thin as die casting, GDC ensures uniform wall sections, minimizing porosity and internal defects. - Tolerances:
Dimensional tolerances are generally ±0.3 mm to ±0.6 mm, depending on part size and mold design. While not as precise as high-pressure die casting, GDC provides good repeatability for medium-to-large parts. - Part Size Range:
Suitable for medium to large castings (from a few kilograms up to several hundred kilograms), such as structural or load-bearing components.
Common Challenges and Solutions – Gravity Die Casting (GDC)
- Slower Production Cycle:
Cycle times are longer compared to high-pressure die casting.
✅ Solution: Use automation (tilt pouring, mechanized ladles) to improve productivity and reduce manual labor. - Limited Thin-Wall Capability:
Difficult to achieve ultra-thin walls (<3 mm) due to gravity-based filling.
✅ Solution: Optimize gating and venting design, preheat molds, and apply tilt-pouring methods to achieve more uniform filling. - Porosity and Shrinkage Defects:
Gas entrapment or non-uniform cooling may lead to shrinkage cavities.
✅ Solution: Employ proper riser and vent design, use chills to control solidification, and optimize pouring temperature. - Surface Finish:
Surface quality is generally rougher than pressure die casting.
✅ Solution: Apply mold coatings, use precision-machined dies, and add post-process machining/polishing. - Die Wear at High Temperatures:
Molds are exposed to thermal stress during repeated pours.
✅ Solution: Use high-quality die steels, apply thermal coatings, and implement mold preheating and cooling systems. - Manual Labor Dependence:
Traditional gravity pouring is labor-intensive and less consistent.
✅ Solution: Introduce semi-automatic or robotic pouring systems to ensure repeatability and safety.
Why Engineers and Buyers Trust Us
- ✅ Over 20 years of die casting experience
- ✅ In-house mold, casting, machining & finishing
- ✅ Certified under ISO 9001 / IATF 16949
- ✅ Fluent English technical support
- ✅ Real-time updates with photos/videos of production
- ✅ Strict project confidentiality & IP protection
How to Work With Us
- ✅ Send Us Your Drawing or Idea
- ✅ Receive Free DFM Feedback
- ✅ We Quote Within 24 Hours
- ✅ Rapid Prototyping or Tooling Starts
- ✅ PPAP or Sample Approval
- ✅ Mass Production & Global Delivery
Gravity Die Casting Frequently Questions & Answers
Can GDC parts be painted or coated?
Yes, surfaces are smooth and can be anodized, powder-coated, or painted to meet aesthetic or protective requirements.
How to choose between Gravity Die Casting and other casting methods?
GDC is ideal for medium-to-large parts with good mechanical strength, smooth surface finish, and medium production volume. High-pressure die casting is better for very thin, intricate, or high-volume parts, while sand casting suits very large, low-volume components.
What are common defects in Gravity Die Casting?
Porosity, cold shuts, surface oxides, and shrinkage are common. Proper mold design and pouring parameters can reduce defects.
How can porosity be minimized in GDC?
Preheating the mold, controlling pouring temperature, and optimizing gating and venting systems can significantly reduce porosity.
What inspection methods are used for GDC parts?
Dimensional inspection (CMM), visual inspection, X-ray or ultrasonic testing for internal defects, and mechanical testing for strength.
What is the typical cost of Gravity Die Casting parts?
Costs depend on material, mold complexity, and production volume. GDC is cost-effective for medium-to-large parts and medium production volumes.
How long does it take to produce a GDC mold?
Permanent steel molds typically take 4–8 weeks to manufacture, depending on complexity.