1. परिचय
Zinc die casting is a widely adopted manufacturing process that plays a critical role in the production of high-precision, high-volume metal components.
Leveraging the excellent castability, आयामी स्थिरता, and strength of zinc alloys, this process supports a wide range of industries—from automotive and electronics to medical and consumer goods.
Zinc’s low melting point (typically around 420–450 °C) allows for rapid cycle times, minimal energy consumption, and extended tool life, making it particularly cost-effective for complex, thin-walled designs.
Unlike other die-casting materials such as aluminum or magnesium, zinc offers superior surface finish quality and exceptional plating compatibility, which are essential for both functional and aesthetic applications.
2. What Is Zinc Die Casting?
जस्ता मेटल सांचों में ढालना is a manufacturing process in which molten zinc or zinc alloys are forced under high pressure into reusable molds, known as dies, to create precise metal components.
The basic principle involves injecting the molten metal into the die cavity, allowing it to solidify, and then ejecting the finished part.
This process can produce parts with tight tolerances, smooth surface finishes, and complex geometries in a relatively short time.
3. Common Zinc Alloys for Die Casting
जस्ता मिश्र धातु used in die casting are formulated to maximize mechanical performance, सतह खत्म, आयामी सटीकता, and ease of processing.
Among the most widely used are the Zamak series (बोझ 2, 3, 5, 7) और ZA alloys (ZA-8, ZA-12, वगैरह।).
Zinc Die Casting Alloys Table
| मिश्र धातु | संघटन (भार%) | प्रमुख विशेषताऐं | सामान्य उपयोग |
| बोझ 3 | एक प्रकार का: ~96%, एएल: 3.9%, घन: 0.03%, मिलीग्राम: 0.02% | Most widely used alloy; उत्कृष्ट आयामी स्थिरता, अच्छी ताकत, किफ़ायती; best for general-purpose casting | Electrical housings, enclosures, उपभोक्ता वस्तुओं |
| बोझ 5 | एक प्रकार का: ~95%, एएल: 3.9%, घन: 1.0%, मिलीग्राम: 0.02% | Higher strength than Zamak 3 due to added copper; slightly reduced ductility; better creep resistance | स्वचालित भाग, appliance hardware, सरंचनात्मक घटक |
| बोझ 2 | एक प्रकार का: ~95%, एएल: 3.9%, घन: 2.7%, मिलीग्राम: 0.02% | Strongest of the Zamak family; lowest ductility; best wear resistance; aging hardenable | Precision gears, wear-resistant mechanical parts |
बोझ 7 |
एक प्रकार का: ~99%, एएल: 0.5–1.0%, घन: <0.001%, मिलीग्राम: 0.003% | Highest ductility in Zamak group; ultra-low impurities; excellent castability and surface finish | Thin-wall castings, miniature components, cosmetic parts |
| ZA-8 (Zinc–Aluminum) | एक प्रकार का: 91%, एएल: 8.4%, घन: 0.8% | Stronger than Zamak 5; usable in hot-chamber machines; better for thin-walled structural parts | High-performance mechanical assemblies, आवास, लीवर |
| ZA-12 | एक प्रकार का: 88%, एएल: 11%, घन: 1.0% | Excellent strength and wear resistance; cold-chamber casting required; moderate castability | Heavy-duty gears, bushings, पुली, कोष्ठक |
4. Die Casting Equipment and Tooling
Zinc die casting typically employs hot-chamber die casting machines, which immerse the injection mechanism directly into the molten metal.
This design enables high-speed operation with minimal energy loss.
Tooling Components:
- Gooseneck system: Transfers molten zinc from the holding pot into the shot sleeve.
- Shot sleeve & plunger: Injects metal into the mold under pressures of 10,000–15,000 psi.
- Die materials: Usually made of H13 tool steel या पी20, with surface treatments like nitriding or PVD coating to resist thermal fatigue and erosion.
Because zinc is less erosive than aluminum, dies can last over 1 million cycles, significantly lowering long-term tooling costs.
5. Zinc Die Casting Process Steps
The zinc die casting process is a precise and efficient method for producing high-volume, high-accuracy metal components.
Thanks to zinc’s exceptional castability, कम गलनांक, और आयामी स्थिरता, the process can achieve tight tolerances, smooth surface finishes, and thin-wall geometries.
Melt Preparation and Temperature Control
- Zinc alloys are typically melted at 420–450 °C (788–842 °F) depending on alloy type and process variation.
- Melting occurs in a furnace integrated with a hot-chamber machine or a separate crucible for cold-chamber machines.
- Precise temperature control is essential to avoid overheating (which causes oxidation and porosity) or underheating (which reduces flowability).
- Degassing और फ़्लक्सिंग may be used to remove entrapped gases and oxides for improved casting quality.
Shot Charging and Injection
- Hot-Chamber Die Casting (most common for zinc):
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- The gooseneck system draws molten zinc directly into the die under hydraulic pressure (7–35 MPa).
- Short cycle times (आम तौर पर <1 second fill time) make the process ideal for high-volume production.
- Cold-Chamber Die Casting (used for ZA-12, ZA-27):
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- Molten zinc is ladled into a shot sleeve, then a piston forces it into the die.
- Required for alloys with higher aluminum content that corrode gooseneck systems.
Cavity Filling and Solidification
- The molten zinc fills the steel die cavity at high speed (up to 1–3 m/s), ensuring it reaches all intricate shapes and thin walls.
- Rapid heat extraction occurs through the die walls, enabling:
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- Quick solidification (within milliseconds to a few seconds)
- High-dimensional accuracy
- Fine-grain structure with improved mechanical properties
- Die venting and vacuum assist may be used to prevent air entrapment and reduce porosity.
Ejection and Die Cycling
- Once the part solidifies, ejector pins push it out of the mold.
- Die surfaces are cooled or lubricated with die release agents to ensure smooth part release and prolong die life.
- ठेठ cycle time for zinc die casting: 20–60 seconds per shot, depending on part complexity and alloy type.
- Dies are then closed and prepared for the next injection—zinc’s fast cooling enables rapid die cycling.
ट्रिमिंग और फ्लैश हटाना
- इजेक्शन के बाद, अतिरिक्त सामग्री (चमक, चकित करना, runners) is trimmed using:
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- Hydraulic or mechanical trimming presses
- CNC deburring systems
- Manual deburring tools for complex geometries
- Proper gating and overflow design minimizes waste and ensures clean part separation.
Inspection and Dimensional Verification
- Initial inspection may include:
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- Visual inspection for flash, सतह दोष, or cold shuts
- Dimensional gauging against CAD or technical drawing specs
- वैकल्पिक X-ray or pressure testing for internal defects
6. Finishing and Post‑Processing of Zinc Die Casting
While zinc alloy die casting is renowned for producing components with excellent surface finish and tight tolerances right out of the mold,
most industrial and consumer applications still require post-processing to meet final specifications.
deburring, ट्रिमिंग, and Flash Removal
After ejection from the die, parts often have अतिरिक्त सामग्री at parting lines and gate areas.
This must be removed to meet design specifications and to ensure safety in handling and assembly.
सामान्य तरीके:
- Mechanical trimming presses: Fast and precise, ideal for high-volume production.
- Hand deburring: Used for small batches or parts with intricate geometries.
- Vibratory finishing: Tumbling parts with abrasive media for smoothing edges and surface preparation.
Goal: Achieve clean contours, remove sharp edges, and prepare parts for coatings.
Surface Cleaning and Pre-Treatment
Surface cleanliness is critical beefore plating, चित्रकारी, या कोटिंग. Zinc’s natural oxide layer and die lubricants must be removed to ensure proper adhesion.
Techniques Include:
- Alkaline cleaning: तेल निकालता है, ग्रीज़ों, and die lubricants.
- Acid pickling: Removes oxides and flash rust.
- Shot blasting or bead blasting: Uniforms the surface and prepares for coatings.
नतीजा: Improves bonding of paints and platings while enhancing cosmetic appearance.
सतही परिष्करण तकनीक
Zinc alloys are highly compatible with decorative and functional coatings, making them ideal for parts requiring appearance or corrosion protection.
Plating
- Nickel Plating: Offers a bright, corrosion-resistant finish, often used in automotive and plumbing.
- Chrome Plating: A mirror-like finish for decorative or wear-resistant surfaces.
- Zinc or Zinc-Nickel Plating: Applied for additional corrosion protection in harsh environments.
पाउडर कोटिंग
- Electrostatic application of a powdered polymer, followed by curing at ~180–200 °C.
- Offers durability, color flexibility, and good resistance to impact and chemicals.
Lacquering or Clear Coating
- Transparent coatings protect plated or polished surfaces without altering appearance.
उष्मा उपचार (Optional for Some Alloys)
Zinc alloys are not typically heat-treated for hardening, लेकिन stress relief treatments may be applied:
- तापमान की रेंज: 80–120 °C for several hours.
- उद्देश्य: Reduce internal stresses from casting or machining, enhance dimensional stability.
Some ZA (Zinc-Aluminum) alloys may undergo age hardening to improve strength over time.
Machining and Secondary Operations
Even though die casting delivers near-net shapes, secondary machining may be required for:
- Threading, ड्रिलिंग, or tapping
- Mating surfaces for assemblies
- Tight-tolerance features not achievable via casting alone
टिप्पणी: Zinc’s excellent machinability makes it ideal for secondary operations, साथ low tool wear और smooth chip formation.
7. Material Properties of Zinc Die Castings
Zinc die castings are valued not only for their excellent castability but also for their robust mechanical and physical properties.
These properties make zinc alloys suitable for precision components requiring high strength, आयामी सटीकता, and good surface finish.
Physical Properties of Zinc Alloys
| संपत्ति | विशिष्ट मूल्य (बोझ 3) | महत्व |
| घनत्व | 6.6–6.8 g/cm³ | Provides strength and rigidity; heavier than aluminum |
| Melting Point Range | 380–390 °C (716–734 °F) | Enables low-energy melting and short cycle times |
| ऊष्मीय चालकता | ~113 W/m·K | Excellent heat dissipation, useful in electronic housings |
| इलेक्ट्रिकल कंडक्टीविटी | ~27% IACS | Suitable for some electrical grounding applications |
| थर्मल विस्तार का गुणांक | 27 × 10⁻⁶ /के | Dimensional changes predictable under thermal cycling |
Mechanical Properties of Zinc Alloys
| संपत्ति | बोझ 3 | बोझ 5 | ZA-8 |
| तन्यता ताकत | ~280 MPa | ~310 MPa | ~350 MPa |
| नम्य होने की क्षमता | ~210 MPa | ~250 MPa | ~275 MPa |
| तोड़ने पर बढ़ावा | ~7–10% | ~6–8% | ~3–6% |
| कठोरता (ब्रिनेल) | 82–90 | 85–95 | 90-100 |
| लोच का मापांक | ~96 GPa | ~96 GPa | ~100 GPa |
| Impact Strength | मध्यम | Slightly lower | Higher than Zamak 3 |
आयामी स्थिरता & रेंगना प्रतिरोध
- आयामी स्थिरता: Zinc die castings can maintain precise tolerances over long periods, especially in moderate temperature environments.
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- विशिष्ट सहनशीलता: ±0.05 mm or better
- रेंगना प्रतिरोध: Limited above 100 ° C. Zinc alloys are not ideal for high-temperature structural loads, but perform well at room to moderately elevated temperatures.
8. Quality Control and Defect Mitigation
Maintaining high product quality in zinc die casting requires robust monitoring and inspection systems.
Typical Defects and Remedies:
| Defect | Cause | शमन |
| सरंध्रता | Air entrapment | Vacuum die casting, गेटिंग डिज़ाइन |
| Cold shuts | Incomplete flow or fill | Raise temperature, improve fluidity |
| चमक | High injection pressure | Tighten die fit, modify clamping |
| Die soldering | Metal fusing to die wall | Apply die lubricant, use coatings |
Non-destructive testing methods such as X-ray inspection, ultrasound, और डाई प्रवेशक परीक्षण are often used to detect internal or surface defects.
9. लाभ & Limitations of Zinc Die Castings
लाभ
Superior Fluidity:
Zinc alloys exhibit excellent fluidity, enabling the production of intricate components with thin walls, as thin as 0.8 मिमी.
This property allows molten zinc to fill complex mold cavities precisely, facilitating the manufacturing of highly detailed parts.
High-Precision Dimensional Accuracy:
Zinc die casting can achieve extremely tight dimensional tolerances, typically within ±0.05-0.1 mm for small-to-medium-sized parts.
This precision often eliminates the need for extensive post-machining, saving both time and cost.
Rapid Production Rates:
Die-casting machines for zinc can operate with short cycle times, आमतौर पर से 10-60 seconds per cycle, depending on part complexity.
This high-speed production capability makes it ideal for mass manufacturing, reducing overall production costs.
Good Surface Finish:
Parts produced through zinc die casting generally have a smooth and glossy surface right out of the mold.
This eliminates the need for many surface-finishing operations and provides an excellent base for further treatments like plating or painting.
लागत प्रभावशीलता:
Zinc is relatively inexpensive compared to many other die-casting metals.
इसके अतिरिक्त, the process generates minimal material waste as excess metal can be easily recycled, further reducing costs.
The lower cost of tooling and equipment also contributes to its economic viability.
Wide Range of Alloy Options:
There are various zinc alloys available, each tailored to specific performance requirements.
उदाहरण के लिए, Zamak alloys offer a balance of strength, संक्षारण प्रतिरोध, and casting properties,
while ZA alloys are known for their high wear resistance, providing flexibility in material selection.
सीमाएँ
सीमित उच्च तापमान प्रदर्शन:
Zinc alloys have low melting points and poor heat resistance.
Their mechanical properties degrade significantly at elevated temperatures (usually above 120°C),
making them unsuitable for applications involving continuous exposure to high heat, such as engine internals in high-performance vehicles.
आकार की बाधाएँ:
The size of zinc die-cast parts is limited by the capacity of die-casting machines and molds.
Producing large-scale components is challenging and costly, as it requires more powerful machines and larger, more expensive molds.
Thermal Sensitivity:
Zinc alloys are sensitive to rapid temperature changes during the die-casting process.
This thermal sensitivity can lead to issues like thermal stresses, मुड़ने, and cracking in the cast parts if the process parameters, such as cooling rates, are not carefully controlled.
Susceptibility to Certain Corrosive Environments:
Although zinc has some inherent corrosion resistance, in highly corrosive environments, especially those with strong acids or alkalis, the material may corrode over time.
While surface treatments can enhance corrosion resistance, it adds to the overall cost.
Regional Alloy Availability:
The production and availability of specific zinc alloys may be limited in some regions.
This can lead to supply chain challenges, longer lead times, and increased costs for sourcing specialized alloys.
10. Applications of Zinc Die Castings
ऑटोमोटिव उद्योग
- Application Areas: Vehicle structural components, interior/exterior trim, and functional parts
- अवयव: Engine mounts, कोष्ठक, door handles, knobs, व्हील हब, grilles, and decorative trims
इलेक्ट्रानिक्स उद्योग
- Application Areas: Electronic enclosures, कनेक्टर्स, and heat management
- अवयव: Plug connectors, device housings, heat sinks for semiconductors, and circuit board fixtures
Consumer Goods Sector
- Application Areas: Home appliances, toys, and decorative products
- अवयव: Handles/knobs for kitchen appliances, toy models, decorative figurines, and hardware for furniture
हार्डवेयर & Plumbing Industry
- Application Areas: Construction fixtures and plumbing systems
- अवयव: Faucets, वाल्व, door locks, टिका, and architectural hardware
Medical Devices Field
- Application Areas: Surgical equipment and biomedical components
- अवयव: Biocompatible instrument housings, implantable device casings (with surface treatment), and diagnostic tool parts
Renewable Energy Sector
- Application Areas: Wind and solar energy infrastructure
- अवयव: पवन टरबाइन कोष्ठक, solar panel mounting systems, and energy storage system enclosures
11. तुलना तालिका: Zinc vs Aluminum vs Magnesium Die Casting
| संपत्ति / विशेषता | Zinc Die Casting | एल्यूमीनियम डाई कास्टिंग | Magnesium Die Casting |
| घनत्व (g/cm g) | 6.6–6.8 | 2.6–2.8 | 1.74–1.84 |
| गलनांक (° C) | 380–390 | 615–660 | 595-650 |
| तन्यता ताकत (एमपीए) | 250-400 | 170–310 | 180-280 |
| नम्य होने की क्षमता (एमपीए) | 210-350 | 120-280 | 150–230 |
| बढ़ाव (%) | 7–15 | 2-8 | 3-10 |
| कठोरता (ब्रिनेल) | 82–120 | 50–110 | 60–90 |
| कास्टेबिलिटी | उत्कृष्ट (पतली दीवारें, तंग सहनशीलता) | अच्छा (less fluid than zinc) | मध्यम (requires controlled conditions) |
| Tool Life | बहुत ऊँचा (तक 1 million shots) | मध्यम (100k–150k shots typical) | Moderate to High |
| संक्षारण प्रतिरोध | अच्छा (can be improved via plating) | मध्यम (needs coating in harsh environments) | अच्छा (especially AZ91D alloy) |
मशीन की |
उत्कृष्ट | अच्छा | अच्छा |
| सतह खत्म | बेहतर (ready for plating or painting) | गोरा (post-processing often needed) | Fair to Good |
| ऊष्मीय चालकता (डब्ल्यू/एम · के) | ~109 | ~150–170 | ~60–90 |
| Unit Cost (material + प्रक्रिया) | कम (low melting point = energy savings) | मध्यम | उच्च (material & tooling costs) |
| पुनरावृत्ति | उत्कृष्ट | उत्कृष्ट | उत्कृष्ट |
| Weight-Saving Potential | कम (high density) | मध्यम | उच्च (lightest of the three) |
| विशिष्ट अनुप्रयोग | Small gears, कनेक्टर्स, enclosures, ट्रिम्स | इंजन ब्लॉक, आवास, structural brackets | Laptop frames, automotive steering wheels, केसिंग |
| पर्यावरणीय प्रभाव | मध्यम (energy-efficient but heavy) | मध्यम से उच्च (ऊर्जा गहन) | निचला (लाइटवेट, less material needed) |
चाबी छीनना:
- जस्ता के लिए आदर्श है उच्चा परिशुद्धि, small, जटिल भाग with superior surface quality and low tooling cost, विशेष रूप से उच्च मात्रा में उत्पादन.
- अल्युमीनियम is preferred for lightweight structural components with moderate strength and higher thermal resistance.
- मैगनीशियम की पेशकश करता है best strength-to-weight ratio, making it suitable for aerospace and portable electronics, but requires more specialized processing and safety controls.
12. निष्कर्ष
Zinc die casting is a mature, precise, and cost-efficient manufacturing process ideally suited for producing complex metal components in high volumes.
इसकी यांत्रिक मजबूती, superior castability, and excellent surface quality continue to make it the preferred choice for industries ranging from automotive to medical devices.
While it has some thermal limitations, its design flexibility, low production cost, and recyclability firmly secure zinc die casting as a leading metal forming technology for the future.
डीआईई द्वारा कस्टम डाई कास्टिंग सेवाएँ
यह उच्च गुणवत्ता प्रदान करता है custom die casting services आपके सटीक विनिर्देशों को पूरा करने के लिए तैयार किया गया.
वर्षों के अनुभव और उन्नत उपकरणों के साथ, हम सटीक धातु घटकों का उपयोग करने में विशेषज्ञ हैं अल्युमीनियम, जस्ता, और मैगनीशियम मिश्र.
हमारी पेशकश:
- OEM & ODM डाई कास्टिंग समाधान
- के लिए समर्थन छोटे से लेकर उच्च मात्रा में उत्पादन
- कस्टम मोल्ड डिज़ाइन और इंजीनियरिंग समर्थन
- सख्त आयामी सहनशीलता और उत्कृष्ट सतह खत्म
- Secondary operations, शामिल सीएनसी मशीनिंग, सतह का उपचार, और विधानसभा
