china casting foundry
Home » Die Casting

Services

Die Casting

The die casting process, which is also academically referred to as permanent mould castings, can generally be classified into three subcategories: Gravity Die Casting, Low Pressure Die Casting, and High Pressure Die Casting. Based on Leesh’s strategy and market demand, we offer all three die casting processes to provide diverse services for global customers. Below is an introduction to our die casting services. If you require any assistance, please contact us at sales@leesh.cn or visit our contact page (https://leesh.cn/contact-us/) for more contact information.

Gravity Die Casting (GDC)

  • Core Principle: Molten metal flows into the cavity of a permanent mold (usually made of cast iron or cast steel) through a runner by its own gravity, solidifies upon cooling, and forms the casting. No additional pressure is applied; filling relies solely on gravity.
  • Process Characteristics:
    • Simple mold structure, mostly with open or semi-open runner designs. Mold manufacturing costs are low, and service life is long (a single mold can produce thousands to tens of thousands of parts).
    • Slow filling speed ensures stable flow of molten metal, resulting in fewer internal defects such as pores and shrinkage cavities, with moderate density.
    • Easy to control during production, with low operational thresholds, suitable for small or medium-batch production.
  • Material Compatibility: Mainly applicable to aluminum alloys, magnesium alloys, copper alloys, and cast iron, especially metals with good fluidity.
  • Typical Applications:
    • Mechanical structural parts (e.g., gearbox housings, brackets, bases);
    • Automotive components (e.g., engine brackets, wheel blanks);
    • General machinery parts (e.g., valve bodies, pump casings);
    • Not suitable for thin-walled, high-precision consumer electronics parts (e.g., smartphone middle frames).
  • Advantages: Low mold costs, good casting density, wide material compatibility, and low scrap rates.
Gravity Die Casting

Low Pressure Die Casting (LPDC)

  • Core Principle: Low-pressure gas (typically 0.05-0.2MPa) is injected into a sealed crucible, pushing molten metal up through a riser tube into the permanent mold cavity. The casting solidifies under pressure retention and cooling.
  • Process Characteristics:
    • Low filling pressure and slow, steady speed ensure stable molten metal flow, resulting in uniform internal structure, fewer pores, and high density (superior to GDC).
    • Higher mold sealing requirements, with riser tubes and pressure control systems. Mold costs are higher than GDC but lower than HPDC.
    • Enables directional solidification, reducing shrinkage defects and ensuring stable mechanical properties of castings.
  • Material Compatibility: Primarily aluminum and magnesium alloys, especially high-purity, high-strength aluminum alloy castings (e.g., aerospace and critical automotive components).
  • Typical Applications:
    • Key automotive parts (e.g., engine blocks, cylinder heads, crankcases, aluminum alloy wheels);
    • Aerospace components (e.g., lightweight structural parts, connectors);
    • High-precision mechanical parts (e.g., hydraulic valve blocks, sensor housings);
    • Mid-to-high-end consumer electronics structural parts (e.g., tablet metal frames, laptop bases).
  • Advantages: High casting density (over 99%), excellent mechanical properties, moderate-to-high dimensional precision (IT10-IT12), surface roughness Ra3.2-12.5μm.
low-pressure-casting-process

High Pressure Die Casting (HPDC)

  • Core Principle: Molten metal is injected into a precision-machined permanent mold cavity at high pressure (typically 10-150MPa) and high speed (injection speed up to 10-50m/s), solidifying rapidly under high pressure for instant forming.
  • Process Characteristics:
    • Ultra-fast filling speed and short production cycles, suitable for mass automated production.
    • High-precision molds (mostly made of H13 hot work die steel) with low cavity surface roughness, resulting in high dimensional precision and good surface quality, reducing subsequent machining.
    • Molten metal solidifies under high pressure, ensuring dense structure, but high-speed filling may trap gas, requiring optimization via vents or vacuum die casting.
  • Material Compatibility: Mainly aluminum, zinc, and magnesium alloys, with aluminum alloy HPDC accounting for over 70% of total HPDC applications.
  • Typical Applications:
    • Core consumer electronics parts (smartphone middle frames, camera brackets, laptop casings, headphone metal components);
    • Automotive lightweight parts (transmission housings, instrument panel brackets, motor casings);
    • Home appliance parts (air conditioner compressor housings, washing machine drum flanges);
    • Precision mechanical parts (small gears, connector housings).
  • Advantages: Extremely high production efficiency (10-60 seconds per mold cycle), high dimensional precision (IT8-IT10), surface roughness Ra1.6-6.3μm, strong thin-wall forming capability (minimum wall thickness 0.5-1mm), suitable for mass production.
High Pressure Die Casting
Comparison DimensionGravity Die Casting (GDC)Low Pressure Die Casting (LPDC)High Pressure Die Casting (HPDC)
Filling PressureGravity only (≈0.001-0.005MPa)Low pressure (0.05-0.2MPa)High pressure (10-150MPa)
Filling SpeedSlow (0.1-0.5m/s)Steady (0.5-2m/s)Ultra-fast (10-50m/s)
Production Efficiency (Single Cycle Time)Moderate (1-5 mins/part)Medium-low (2-8 mins/part)Extremely high (10-60 secs/part)
Dimensional ToleranceIT12-IT14IT10-IT12IT8-IT10
Surface Roughness (Ra)6.3-25μm3.2-12.5μm1.6-6.3μm
Casting DensityModerate (95%-97%)High (over 99%)High (97%-99%)
Thin-Wall Forming Capability (Min. Thickness)3-5mm2-3mm0.5-1mm
Mold CostLow (tens of thousands to several hundred thousand yuan/mold)Medium (several hundred thousand to one million yuan/mold)High (over one million yuan/mold)
Material CompatibilityAluminum, magnesium, copper alloys, cast ironAluminum, magnesium alloys (mainly)Aluminum, zinc, magnesium alloys
Typical Application ScenariosMechanical structural parts, general machinery accessoriesKey automotive parts, aerospace componentsConsumer electronics parts, automotive lightweight components
Subsequent Machining RequirementHigh (requires machining for size and surface optimization)Medium (some critical surfaces need machining)Low (near-net shape, only local finishing)
Batch SuitabilitySmall, medium batchesMedium, large batchesLarge, extra-large batches
Main Defect RisksShrinkage, incomplete fillingMinor shrinkage (controllable via process optimization)Porosity, oxide inclusions

 1. Material Specifications

Material TypeStandards & Grades
Aluminum Alloy
  • General & Die Casting Grades: ADC12, ADC10, A360, A380, A356, 6061, 6063, ADC3, ADC5, A383
  • Gravity Casting Grades: ZL104, A356, A360, A413
  • Regional Standards:
    • USA: A360, A380, A356, A383
    • Europe: EN-AC 46100, EN-AC 46000, EN-AC 47100
    • Japan: ADC12, ADC3, ADC5, ADC10
  • General Standards: ISO3522-84, ASTM B85-96, JIS H5302:2000, EN1706:1998
  • Others: Customizable per customer requirements
Magnesium Alloy
  • Grades: AZ91D, AM60B
  • Standards: ISO/DIS16220-1999, ASTM B93/B93M-98, EN1754-1997
Zinc Alloy
  • Grades: ZA3#, ZA5#, ZA8#, ZZnAl4Y YX040, ZZnAl4Cu1Y YX041, ZZnAlCu3Y YX043, ZP0400 ZP3, ZP0410 ZP5, ZP0430 ZP2, ZP0810 ZP8, ZP1110 ZP27, ZP2720 ZP27, ZP0010 ZP16, Z13001, Z15001, Z19001, ZDC1, ZDC2
  • Regional Standards:
    • China (GB/T13812-92): ZZnAl4Y YX040, ZZnAl4Cu1Y YX041, ZZnAlCu3Y YX043
    • Europe (EN 12844-1998): ZP0400 ZP3, ZP0410 ZP5, ZP0430 ZP2, ZP0810 ZP8, ZP1110 ZP27, ZP2720 ZP27, ZP0010 ZP16
    • USA (ASTM B6-2003): Z13001, Z15001, Z19001
    • Japan (JIS H5301-1990): ZDC1, ZDC2
  • Others: Customizable per customer requirements

2. Dimensional Tolerance

Processing TypeTolerance Range
Die Casting± 0.02mm

3. Surface Treatment

Unified surface treatment methods (covering all processes/products):

  • Electroplating: Chrome Plating, Zinc Plating, Nickel Plating
  • Chemical treatment: Electrophoresis, Anodization, Passivation, ED-Coating
  • Physical finishing: Polishing, Grinding, Sandblasting, Shot blast
  • Coating: Powder coating, Spray painting, Baking paint, Oil spraying, Electrostatic spraying
  • Special treatment: Screen printing/Transfer printing, Laser engraving, Oil filling

4. Quality Assurance & Inspection

CategoryDetails
Inspection Methods
  1. In-house inspection: 100% inspection on critical dimensions and appearance
  2. Third-party inspection: Available upon customer requirement
Testing FacilitiesThree-dimensional measuring instrument (CMM), X-ray flaw detector, Salt spray test box, Dynamic balance detector, Pneumatic detection
Quality Control ItemsSurface condition, Dimensions, Threads, Balance, Gas Density, Material composition

5. Mold Parameters

ParameterSpecifications
Mold MaterialH13 Steel, 2344 Steel, DIEVAR Steel
Mold Cavity1 cavity, 2 cavities, 4 cavities, 8 cavities
Mold Lifetime50,000-100,000 shoots

6. Product Features & Advantages

  • High machining accuracy: Flatness within 0.1mm; surface roughness Ra1.6 after machining
  • Mechanical performance: High strength, non-deformable, good electrical and thermal conductivity
  • Assembly & durability: Seamless assembly structure; corrosion resistance; passes 96-hour Salt Spray Test
  • Aesthetics: High-finish, smooth appearance

7. Application Fields

  • Electronics
  • Camera Support Equipment
  • Train Braking Systems
  • Electrical Lighting
  • Furniture
  • Communication Systems
  • Automotive industry
  • Others (per customer demand)

Navigation

Product Category

Contact us

Social Media

Facebook Youtube Linkedin Whatsapp
 Copyright © LEESH HOLDINGS CO., LTD.
Scroll to Top