Zinc Bars and Ingots

Zinc Bars and Ingots are solid, rectangular or specially cast blocks of high-purity zinc metal used across various industrial applications. Produced through smelting and refining processes, these forms of zinc serve as primary raw materials for galvanizing, alloy production, die casting, chemical manufacturing, and corrosion control systems.

Zinc is valued for its excellent corrosion resistance, moderate strength, and ability to form protective coatings on steel and iron, making it one of the most important non-ferrous metals in modern industry.

Chemical Composition

Typical Zinc Bar / Ingot Composition

ElementTypical Content
Zinc (Zn)99.9% – 99.995%
Lead (Pb)≤ 0.003%
Iron (Fe)≤ 0.002%
Cadmium (Cd)≤ 0.002%
Copper (Cu)≤ 0.001%
Aluminum (Al)Trace

Common Commercial Grades

SHG Zinc (Special High Grade) – ≥ 99.995%
Prime Western Zinc (PW) – ≥ 99.9%
Galvanising-grade zinc – controlled alloying additions

Key Mechanical Properties

Zinc bars and ingots are not structural materials, but their mechanical properties influence handling and remelting behavior.

PropertyTypical Value
Tensile Strength100–150 MPa
Yield Strength30–50 MPa
Elongation10–30% (temperature dependent)
Hardness~30–40 HB
Modulus of Elasticity~108 GPa
Creep ResistanceLow

Mechanical Behavior Notes

Brittle at room temperature
Ductile between 100–150°C
Easily remelted; mechanical properties are secondary in use

Physical Properties

PropertyValue
Density7.13 g/cm³
Melting Point419.5°C
Boiling Point907°C
Thermal Conductivity~116 W/m·K
Electrical Conductivity~28% IACS
Coefficient of Thermal Expansion30.2 µm/m·°C
Crystal StructureHexagonal Close-Packed (HCP)
AppearanceBluish-silver metallic

Strengthening & Metallurgical Behavior

Metallurgical Structure

Pure zinc exhibits an HCP crystal lattice
Limited slip systems → brittleness at room temperature
Uniform grain structure in electrolytic zinc

Strengthening Behavior

Zinc bars and ingots:

Cannot be heat-treated
Cannot be precipitation hardened

Strength improvement occurs only through:

Grain refinement during solidification
Minor work hardening (limited)
Alloying (primary route for strength)

In most industries, zinc bars and ingots are melted and alloyed, not used directly as finished parts.

Key Characteristics

1. High Purity & Consistency

Controlled chemistry
Minimal impurities
Predictable melting and reaction behavior

2. Excellent Corrosion Resistance

Forms protective zinc oxide/carbonate layer
Stable during storage and transport

3. Low Melting Point

Energy-efficient remelting
Ideal for casting and alloy production

4. Electrochemical Activity

Acts as sacrificial metal
Used in cathodic protection systems

Refining & Processing Properties

Refining Route

Zinc ore roasting
Leaching and purification
Electrolytic deposition
Cathode melting
Casting into bars or ingots

Processing Advantages

Low oxidation losses during melting
Excellent fluidity in molten state
Easy alloying with aluminum, copper, magnesium
Compatible with continuous and batch furnaces

Handling & Storage

Non-hazardous
Long shelf life
Easy stacking and transport

Available Forms

Zinc is commercially supplied as:

Standard zinc ingots (20–25 kg)
Jumbo ingots (500–1,000 kg)
Zinc bars
Zinc slabs
Zinc pigs
Custom cast shapes
High-purity laboratory ingots

Applications of Zinc Bars & Ingots

1. Galvanizing Industry

Hot-dip galvanizing baths
Continuous galvanizing lines
Alloyed galvanizing zinc formulations

2. Alloy Manufacturing

Brass (Cu–Zn)
ZAMAK die-casting alloys
ZA alloys
Zinc-magnesium alloys

3. Chemical Industry

Zinc oxide
Zinc sulfate
Zinc chloride
Pigments and catalysts

4. Battery & Energy

Zinc-carbon batteries
Alkaline batteries
Zinc-air battery anodes

5. Metallurgy

Cementation processes
Precious metal recovery
Smelting additives

Advantages of Zinc Bars & Ingots

✔ High purity and consistent quality
✔ Easy to melt and process
✔ Low energy requirement
✔ Excellent corrosion resistance
✔ Fully recyclable
✔ Cost-effective primary metal

Limitations

❌ Low mechanical strength
❌ Not suitable for direct structural use
❌ Brittle at room temperature
❌ Performance degrades at high temperatures

Why Choose Zinc Bars & Ingots?

Zinc bars and ingots are chosen when reliability, purity, and processing efficiency are critical.

Industries prefer zinc bars & ingots because they:

Serve as a universal zinc feedstock
Ensure predictable alloy and coating quality
Reduce process contamination
Support large-scale industrial production
Meet international standards (ASTM, ISO, EN, IS)

Zinc bars and ingots represent the foundation of the global zinc supply chain. While mechanically soft, their high purity, low melting point, corrosion resistance, and electrochemical behavior make them indispensable for galvanizing, alloy production, chemical processing, and energy applications.

They are not final-use structural products—but they are the essential building blocks behind many of the world’s most durable and corrosion-resistant materials.