Titanium Anodes For Electrogalvanizing

With the rapid growth of the automotive industry, the demand for high-quality automotive steel has increased significantly. In vehicle manufacturing, coated steel plates are widely used to replace conventional cold-rolled and hot-rolled plates, providing superior corrosion resistance for car bodies.

Among these coatings, galvanized steel plates (zinc-based alloy coatings) are the most representative and fastest-growing category. Automotive manufacturers extensively apply coatings such as:

Pure zinc

Zinc-nickel alloys (Zn–Ni)

Zinc-iron alloys (Zn–Fe)

Zn–Ni–Co–Mo, Zn–Co–Mo, Zn–Al alloys

Zinc-Nickel Alloy Coated Steel Plates

Advantages in Forming: Reduced pulverization and peeling during stamping → excellent formability.

Surface Quality: Very few dents or defects after stamping.

Industry Adoption:

Toyota (Japan): interior & exterior car body panels.

Ford (USA): body panels for corrosion resistance.

Electro-galvanized Ni-alloy steel has thus become the fastest-growing galvanized material in the automotive industry.

Importance of Titanium Anodes

The anode material is a critical factor in the high-speed electroplating process. It directly affects the uniformity, lifespan, and energy efficiency of the plating system.

Soluble Anodes: Traditional but require frequent replacement.

Insoluble Titanium Anodes: Preferred due to:

Improved coating uniformity

Reduced energy consumption

Lower maintenance (no frequent replacement)

Longer lifespan, ensuring continuous operation

As a result, Ir–Ta oxide coated titanium anodes have been widely adopted in automotive galvanizing lines.

Electrolyte & Performance

Electrolyte Composition (steel plate galvanizing):

1 mol/L ZnSO₄

0.7 mol/L Na₂SO₄

pH: 1.5

Titanium Anode Performance:

Type: Ir–Ta oxide coating

Service Life: ~10,000 hours (417 days) at 100 A/dm², 60 °C

Case Study – USIMINAS Steel Plant (Brazil, 2017)

Working Conditions:

Electrolytic zinc solution: pH 1.3 – 2.0

Temperature: 65 °C

Density: 1.25 kg/L

Current: 23,000 A

Voltage: 24 V

Anode Specifications:

Dimensions: 5 × 995 × 1750 mm (with holes & bolts)

Coating:

One side: Platinum plating

Other side: Ir/Ta mixed oxide coating

Features:

Long working life under high current density

Stable coating performance

Excellent corrosion resistance in acidic electrolytes