Electrolytic Zinc (often referred to as High Purity Zinc) is produced through an electrolysis refining process that yields zinc with a purity level of 99.95% – 99.99%. This high level of purity provides superior corrosion resistance, uniform composition, and excellent metallurgical properties, making it suitable for a wide range of industrial and chemical applications.
Electrolytic zinc is widely used in galvanizing, alloy production, die-casting, batteries, and chemical manufacturing due to its consistent quality and performance.
Chemical Composition
| Element | Typical Content |
|---|---|
| Zinc (Zn) | ≥ 99.95% – 99.995% |
| Lead (Pb) | ≤ 0.003% |
| Iron (Fe) | ≤ 0.002% |
| Cadmium (Cd) | ≤ 0.002% |
| Copper (Cu) | ≤ 0.001% |
| Aluminum (Al) | Trace |
Key Mechanical Properties
Electrolytic zinc shares the mechanical behavior of pure zinc but with greater consistency and predictability due to controlled refining
| Property | Typical Value |
|---|---|
| Tensile Strength | 100–150 MPa |
| Yield Strength | 30–50 MPa |
| Elongation | 10–30% (temperature dependent) |
| Hardness | ~30–40 HB |
| Modulus of Elasticity | ~108 GPa |
| Creep Resistance | Low |
Mechanical Behavior Notes
Brittle at room temperature
Highly ductile between 100–150°C
Not suitable for load-bearing structural use
Ideal for coating, sacrificial, and electrochemical roles
Physical Properties
| Property | Value |
|---|---|
| Density | 7.13 g/cm³ |
| Melting Point | 419.5°C |
| Boiling Point | 907°C |
| Thermal Conductivity | ~116 W/m·K |
| Electrical Conductivity | ~28% IACS |
| Thermal Expansion | 30.2 µm/m·°C |
| Crystal Structure | Hexagonal Close-Packed (HCP) |
| Appearance | Bright bluish-silver |
Strengthening & Metallurgical Behavior
Crystal & Microstructure
HCP crystal lattice limits slip systems
Leads to low ductility at ambient temperature
Purity ensures uniform grain structure
Strengthening Behavior
Electrolytic zinc:
Cannot be precipitation-hardened
Cannot be heat-treated
Strength improvement is limited to:
Grain refinement during solidification
Minor work hardening
Alloying (primary strengthening route)
Most industrial strength applications therefore use electrolytic zinc as a base metal for zinc alloys, not as a final structural material.
Key Characteristics
1. Extremely High Purity
Consistent chemical and electrochemical behavior
Low dross formation during galvanizing
Superior surface finish
2. Exceptional Corrosion Protection
Forms stable zinc oxide / carbonate layer
Acts as a sacrificial anode to steel
Performs well in marine and industrial atmospheres
3. Excellent Electrochemical Performance
Ideal for batteries and cathodic protection
Predictable dissolution rate
4. Low Melting & Energy Efficiency
Enables efficient smelting, casting, and coating
Lower energy consumption compared to other non-ferrous metals
Refining & Processing Properties
Electrolytic Refining Process
Zinc ore is roasted to zinc oxide
Leached using sulfuric acid
Zinc sulfate solution purified
Zinc deposited on cathodes via electrolysis
Cathode sheets melted into ingots
Processing Advantages
Very low impurity content
Excellent melt fluidity
Minimal oxidation losses
Stable composition batch-to-batch
Workability
Castable with excellent surface finish
Rollable and extrudable at elevated temperatures
Not suitable for welding in pure form
Available Forms
Electrolytic zinc is supplied in multiple industrial forms:
SHG zinc ingots
Jumbo ingots
Zinc slabs
Zinc sheets & plates
Zinc rods & bars
Zinc wire
Zinc powder / dust
Zinc granules
Zinc anodes (marine & pipeline)
Applications of Electrolytic Zinc
1. Galvanizing Industry
Hot-dip galvanizing
Continuous galvanizing lines
Electro-galvanizing
2. Battery Manufacturing
Zinc-carbon batteries
Alkaline batteries
Zinc-air batteries
3. Chemical Industry
Zinc oxide
Zinc sulfate
Pigments, rubber, ceramics
Pharmaceuticals and agrochemicals
4. Alloy Production
Brass
Zamak alloys
Zinc-aluminum die-casting alloys
Special zinc-magnesium alloys
5. Cathodic Protection
Sacrificial anodes for:
Ships and offshore platforms
Pipelines
Storage tanks
Underground structures
Advantages of Electrolytic Zinc
✔ Highest commercial zinc purity
✔ Excellent corrosion protection
✔ Superior galvanizing performance
✔ Predictable electrochemical behavior
✔ Low impurity-related defects
✔ 100% recyclable
✔ Environmentally sustainable
Limitations
❌ Low mechanical strength
❌ Brittle at ambient temperature
❌ Poor high-temperature performance
❌ Not suitable for structural components
Why Choose Electrolytic Zinc?
Electrolytic zinc is the preferred choice when purity, consistency, and performance reliability are critical.
It is chosen because it:
Produces superior galvanizing coatings
Extends steel service life dramatically
Ensures stable battery and chemical performance
Reduces process contamination
Meets international quality standards (ASTM, ISO, EN, JIS)
Electrolytic zinc represents the highest standard of refined zinc metal, offering unmatched purity, corrosion resistance, and electrochemical consistency. While mechanically soft, its importance lies in protection, coating, alloying, and chemical transformation, making it indispensable to modern infrastructure, energy systems, and manufacturing industries.