Vollständiger Leitfaden für elektrogalvanisierten Stahl (EG)

Dieser Artikel ist ein vollständiger Leitfaden für Blech, der alles von der Materialdefinition bis zur projektbasierten Materialauswahl abdeckt. Er erläutert die einzigartigen Vorteile von elektrogalvanisiertem Stahl (EG) sowie seine praktischen Leistungsgrenzen und hilft Ihnen, genauere Materialentscheidungen zu treffen, wenn Sie zwischen CR, EG und HDG wählen.
Glatte & gleichmäßige Oberfläche

Ideal für sichtbare Blech-
und Metallteile

Gute Umformbarkeit

Geeignet zum Biegen
und Stanzen

Lackfreundliche Oberfläche

Hervorragende Basis für Pulver-
beschichtung und Lackierung

Elektrolytisch verzinkter Stahl: Die Grundlagen

Elektroverzinkter Stahl, oft bezeichnet als EG oder EGI, wird typischerweise hergestellt unter Verwendung von kaltgewalztem Stahl als Substrat, mit einer Zinkbeschichtung, die durch ein elektrolytisches Abscheideverfahren. aufgebracht wird. EG bezieht sich speziell auf die Elektroplattierung mit Zink als Beschichtungsmaterial, und es wird weit verbreitet in Anwendungen eingesetzt, die eine verbesserte Korrosionsbeständigkeit erfordern. Die abgeschiedene Beschichtung liegt üblicherweise im Bereich von 5–20 μm , ist aber hochgradig gleichmäßig und weist eine geringe Porosität.

auf. Da die Zinkbeschichtung auf elektrogalvanisiertem Stahl relativ dünn, präzise gesteuert und glatt ist, bewahrt sie einen Großteil der ursprünglichen Oberflächentextur des kaltgewalzten Substrats. Das macht sie besonders geeignet für Komponenten mit strengen Anforderungen an das Erscheinungsbild.

Der Unterschied zwischen EG und “allgemeiner Elektroplattierung” besteht darin, dass die Zielanwendung viel spezifischer ist. Allgemeine Elektroplattierung kann auf eine breite Palette von Materialien angewendet werden, während elektrogalvanisierter Stahl sich speziell auf Zink-Elektroplattierung auf Stahlblech. bezieht. Mit anderen Worten, Elektrogalvanisierung ist ein spezifisches Verfahren innerhalb der breiteren Kategorie der Galvanisieren.

Electro-galvanized steel sheet with a smooth zinc coating used for precision sheet metal fabrication

Kernmaterialeigenschaften von elektrogalvanisiertem Stahl (EG)

Oberflächenqualität und Gleichmäßigkeit

Die Beschichtungsdicke ist hochgradig gleichmäßig, und die Oberfläche ist glatt mit keinem erkennbaren Zinkblumenmuster, was sie ideal macht für Produkte mit hohen Anforderungen an das Erscheinungsbild und für lackierte oder beschichtete Oberflächen. Sie bietet außerdem hervorragende Maßgenauigkeit und Ebenheit, was die Unterstützung von Stanzen und automatisierter Fertigung fördert.

Korrosionsbeständigkeit

Elektrogalvanisierter Stahl verbessert die Korrosionsbeständigkeit durch beide Barriereschutz und Opferschutz durch seine Oberflächenzinkschicht. Unter Standard-Salzsprühtestbedingungen beginnt nicht-passiviertes EG typischerweise Weißrost nach etwa 48–72 Stunden. Mit Passivierungsbehandlung kann die Weißrostbeständigkeit normalerweise auf mehr als 200–500 Stunden.

Umformbarkeit beim Stanzen und Tiefziehen

Die dünne Beschichtung hat nur einen begrenzten Einfluss auf die Umformbarkeit des Materials, wodurch EG gut geeignet ist für Tiefziehen, komplexes Stanzen, und kontinuierliches Biegen. Bei Tiefziehanwendungen hilft geeignete Schmierung, Reibung zu kontrollieren und Werkzeugverschleiß zu reduzieren.

Schweißbarkeit

EG bietet gute Punktschweißbarkeit. Im Vergleich zu unbeschichtetem Stahl kann die Schweißzeit länger sein, und Elektroden werden eher durch Zinkkontamination beeinträchtigt. Für stabile Ergebnisse ist es wichtig, die richtigen Elektrodenmaterialien und geeignete Kühlbedingungen.

Lackierbarkeit und Beschichtungshaftung

Die glatte Oberfläche von elektrogalvanisiertem Stahl ermöglicht nach geeigneter Vorbehandlung eine hervorragende Beschichtungsleistung, was die Haftung von Lack oder Pulverbeschichtungen. deutlich verbessert. Dies macht ihn besonders geeignet für Teile wie Gerätegehäuse und Gehäuse elektronischer Geräte , die lackiert oder pulverbeschichtet werden müssen.

Normen und Gütesysteme für elektrogalvanisierten Stahl (EG)

Verschiedene Länder und Regionen haben eigene Normen für elektrogalvanisierten Stahl (EG). entwickelt. Obwohl sich die Systeme in Namenskonventionen und Gütebezeichnungen unterscheiden, sind sie in ihrer Struktur weitgehend ähnlich. Die am häufigsten verwendeten Normen, Namensformate und Güten sind unten aufgeführt.

Incoming inspection of electro-galvanized steel sheet with measuring tools and material certification documents

Vergleich gängiger Normensysteme und Bezeichnungen

Normensystem Gängiges Bezeichnungsformat Typische Güten / Beispiele Anwendungshinweise
JIS G 3313 (Japan) SECC, SECD, SECE, usw. SECC (Allgemeine Verwendung), SECD (zum Stanzen), SECE (zum Tiefziehen) Basierend auf kaltgewalzten Stahlsubstraten wie SPCC, SPCD und SPCE; weit verbreitet in Haushaltsgeräten, Büroausstattung und Automobil-Stanzteilen
EN 10152 (Europa) DC01+ZE, DC03+ZE, DC04+ZE, usw. DC01+ZE (allgemeine Kaltumformung), DC03+ZE (Tiefziehen), DC04+ZE (extratiefes Tiefziehen) Basierend auf kohlenstoffarmem kaltgewalztem Stahl der DC-Serie; ZE kennzeichnet eine elektrogalvanische Zinkbeschichtung
ASTM A879/A879M (U.S.) ZE coating, with coating mass expressed in g/m² ZE 20/20, ZE 40/40 (equal coating); ZE 30/60 (differential coating) Used where coating mass on each side must be specified; the coating is smooth and free of visible spangle
GB/T 15675 (China) DC01+ZE, DC03+ZE, etc. DC01+ZE, DC03+ZE, DC04+ZE Closely aligned with the EN system; ZE indicates a pure zinc coating, while ZN indicates a zinc-nickel alloy coating

Common Grades and Formability Levels

Güte Typische Verwendung Umformbarkeit Typische Anwendungen
SECC / DC01+ZE General forming and simple stamping Norm Appliance housings, office equipment covers, internal brackets, general structural parts
SECD / DC03+ZE Stamped parts Gute Appliance panels, office equipment housings, general stamped components
SECE / DC04+ZE Tiefgezogene Teile Very good Appliance inner liners, automotive inner panels, complex deep-drawn parts
SECF / DC05+ZE Extra deep-drawn parts Ausgezeichnet Deep-drawn appliance housings, complex automotive inner panels
SECIF / DC06+ZE Special deep-drawn parts Ausgezeichnet Automotive outer panels, high-appearance parts requiring complex forming

Hinweis: Designations such as SECC, SECD, and SECE do not indicate different coating types. They identify different formability grades und application categories. The base material is SPCC, SPCD, or SPCE, which correspond to the JIS G 3141 standard for cold-rolled steel.

How Electro-Galvanized Steel (EG) Differs from Cold-Rolled Steel and Hot-Dip Galvanized Steel

Put simply, EG, CR, and HDG represent a range of material options that run from no corrosion protection, to heavy-duty corrosion protection, to a more balanced combination of high surface quality und moderate corrosion resistance.

  • Electro-Galvanized Steel (EG) vs. Cold-Rolled Steel (CR)：Elektroverzinkter Stahl is essentially cold-rolled steel with an added zinc coating. As a result, it offers better corrosion resistance and is more suitable for parts that require basic rust protection.

  • Electro-Galvanized Steel (EG) vs. Hot-Dip Galvanized Steel (HDG/GI)：The coating on elektrogalvanisierter Stahl is thinner than that of hot-dip galvanized steel, but the surface quality is higher. This makes EG a better choice for projects that require both good appearance und moderate corrosion resistance.

    By contrast, hot-dip galvanized steel has a thicker coating and therefore provides stronger corrosion protection, but its surface is usually rougher and its formability is generally less refined. It is better suited to long-term outdoor applications.

  • Electro-Galvanized Steel (EG) vs. Zinc-Iron Alloy and Other Coated Steels：Elektroverzinkter Stahl has a pure zinc coating, which gives it a well-balanced combination of corrosion resistance und formability. Zinc-iron alloy coated steel generally offers better surface performance than EG, but at a higher cost. Other coated steels, such as aluminum-zinc und zinc-aluminum-magnesium, can deliver even better weather resistance in specific environments.

Visual comparison of electro-galvanized steel, cold-rolled steel and hot-dip galvanized steel for sheet metal fabrication

Comparison Table: EG, CR, and HDG

Materialtyp Oberflächenqualität Korrosionsbeständigkeit Umformbarkeit Schweißbarkeit Paintability Typische Anwendungen
CR Cold-Rolled Steel High, with a clean and smooth surface Low, requires additional rust protection Gute Weldable under normal conditions Can be coated, but the pre-treatment and corrosion protection system must be fully built out Indoor parts, fully painted components, cost-sensitive applications
EG Electro-Galvanized Steel Very high, with a uniform coating Mäßig, better than CR Good to very high, with grades available for deep drawing Well suited to spot welding and laser welding, though parameters must be controlled Very paint-friendly, ideal for powder coating, painting, and visible parts Home appliances, office equipment, electronic enclosures, visible panels, inner and outer equipment panels
HDG Hot-Dip Galvanized Steel Fair to good, though ultimate surface appearance is not usually the main priority Hoch, with stronger long-term corrosion protection Depends on the grade and coating weight Weldable, but the process window differs from EG Can be coated, but fine surface preparation is often needed for high-appearance finishes Construction, structural parts, humid environments, long-term exposed applications, heavy-duty corrosion protection scenarios

Surface Conditions and Post-Treatment Options for Electro-Galvanized Steel (EG)

Common EG Surface Conditions and Typical Applications

Surface Condition / Post-Treatment Function Suitable for Painting or Coating Typische Anwendungen
Passivierung Provides temporary protection and reduces the risk of Weißrost Generally acceptable as a pre-treatment condition for later processes Standard storage and transportation, general equipment parts
Chrome-free / Cr-VI-free passivation Provides similar temporary protection while meeting environmental compliance requirements Depends on the downstream coating system, but is usually more coating-friendly Home appliances, electronic equipment, and projects with stricter environmental requirements
Oiling Improves protection during storage and transport, while also enhancing forming lubrication Usually requires degreasing before painting Stamped parts, general storage and transportation
Phosphatieren Improves temporary resistance to white rust and provides a better bonding base for organic coatings Ja Powder-coated parts, painted parts, appearance components
Phosphating + passivation + oiling Provides stronger storage and transport protection while also supporting formability Still depends on the downstream coating system Projects with longer supply chain cycles or more demanding transportation conditions

Hinweis: A phosphate layer can serve as an effective bonding base for subsequent organic coatings, while also providing temporary protection against Weißrost during storage and transportation.

Typical Fabrication Processes for elektrogalvanisiertem Stahl (EG)

In der Blechfertigung, elektrogalvanisierten Stahl (EG) is a very commonly used material—and for many applications, an especially practical one. Most forming processes commonly used for bare steel sheet are also suitable for EG, and it performs particularly well in Tiefziehen. That said, factors such as tool condition, lubrication, und surface cleanliness still have a major impact on processing results, so proper process control remains essential.

Common EG Fabrication Processes and Key Control Points

Verfahren Process Compatibility Häufige Probleme Control Recommendations
Laserschneiden Gute Exposed cut edges, insufficient edge protection after localized heating Consider it together with the downstream painting or edge-sealing strategy
CNC punching / stamping Good to very high Scratches, indentations, localized tearing, die pickup Pay close attention to lubrication, tool condition, und matching the right material grade
Biegen Gute Surface damage on the outer bend radius, springback control Plan the direction of visible surfaces and use protective film or pads where needed
Deep drawing Fairly good to high Surface damage under extreme forming conditions, narrower process window Choose a higher-formability grade and validate both lubrication and tooling
Spot welding / resistance welding Gute Weld inconsistency, spatter, reduced electrode life Adjust welding current and maintain electrodes with regular dressing
Pre-treatment before powder coating / painting Essential Direct painting may cause unstable adhesion or inconsistent appearance Determine the required degreasing, phosphating, or other pre-treatment based on the supplied surface condition

Typical Applications for elektrogalvanisiertem Stahl (EG)

Because of its strong overall performance, elektrogalvanisierten Stahl (EG) is widely used in the following industries and product categories:

  • Appliance housings and internal brackets: refrigerator, washing machine, air conditioner, and microwave housings and structural parts；

  • Office equipment components: copiers, printers, monitors, computer housings, and similar products；

  • Steel furniture: filing cabinets, office partitions, and drawer slides；

  • Electrical and electronic components: computer cases, server housings, control cabinets, and telecommunications equipment；

  • Automotive stampings and supporting parts: inner door panels, inner hood panels, dashboard brackets, and seat structures；

  • Painted decorative and functional parts: a wide range of components that require Pulverbeschichtung oder spray painting

Electro-galvanized steel used in appliance housings, office equipment parts, cabinets and painted sheet metal components

Application Scenarios and Recommended Material Selection Logic

Anwendung Oberflächenanforderung Corrosion Requirement Is EG Recommended? Grund
Appliance housings (visible surfaces) Hoch Mäßig Empfohlen Smooth surface, well suited to painting, and sufficient corrosion resistance for indoor use
Automotive inner panels (non-visible parts) Mäßig Mäßig Empfohlen Good formability, good weldability, and corrosion resistance suitable for interior vehicle components
Office equipment housings Hoch Mäßig Empfohlen Excellent paint compatibility with a good balance of appearance and corrosion resistance
Outdoor structural parts Mäßig Hoch Not recommended (HDG is a better choice) EG has a thinner coating and does not provide enough long-term corrosion protection for outdoor exposure
Equipment used in high-humidity environments Mäßig Relatively high Use with caution (enhanced post-treatment is required) Can be used if passivation and coating are properly applied; otherwise HDG should be considered
Complex deep-drawn parts (such as appliance inner liners) Mäßig Mäßig Empfohlen Excellent formability, especially suitable for Tiefziehen applications

How to Choose the Right elektrogalvanisiertem Stahl (EG) for Your Project

When reviewing a new project, material selection should be evaluated across five key factors:

service environment → appearance requirements → fabrication method → cost target → delivery requirements

EG Material Selection Guide

Project Condition Material Recommendation Is EG or Another Material More Suitable? Hinweise
Dry indoor environment, standard appearance requirements CR or EG EG is the better option EG offers better corrosion resistance than CR, with moderate cost
Indoor humid environment with some corrosion-resistance requirements EG EG EG provides better corrosion resistance than CR, while costing less than HDG
Outdoor exposure or heavily corrosive environment HDG / zinc-aluminum-magnesium EG is not recommended EG has a thinner coating and does not offer sufficient long-term corrosion resistance outdoors
High appearance requirements with painting or coating EG EG Smooth surface and good coating adhesion make it ideal for painted parts
Deep drawing or complex stamping EG EG The thin coating has minimal effect on formability, and EG performs well in deep-drawing applications
Simple bending, low-strength parts CR or EG EG is the better option EG provides better corrosion resistance while still keeping cost under control
High-strength structural parts (thick gauge) HDG or structural steel EG is not recommended EG is typically used for thin sheet; thicker structural applications are usually better suited to HDG
Limited budget, short service life CR CR is more suitable for short-term use If budget is tight and the operating environment is dry, CR can be a practical choice

Common Issues Often Overlooked in Procurement and Drawing-Based Custom Manufacturing

In real-world projects, the following issues are often overlooked, which can lead to quality problems oder fit-up issues after delivery:

  • Specifying only the grade but not the coating requirement: For example, calling out SECC without defining the coating weight oder surface condition can result in corrosion resistance or appearance that falls short of expectations.

  • Specifying only “EG” without the surface condition: If post-treatments such as passivation, phosphating, or oiling are not defined, downstream fabrication and coating performance may be affected.

  • Focusing only on corrosion resistance while ignoring later painting or coating: If pre-treatment requirements are not considered, coating adhesion may be poor.

  • Not identifying visible surfaces on the drawing: If the required appearance grade is not clearly marked, the delivered surface quality may be inconsistent.

  • Overlooking the effect of stamping or welding on the surface: Damage to the zinc layer may occur, and corrosion repair may be needed in affected areas.

  • Ignoring the impact of packaging and transportation on white rust and scratches: Humid storage or poor packaging protection can lead to Weißrost oder mechanical surface damage.

It is strongly recommended that the technical agreement und drawings clearly specify the following: material grade, coating weight, surface condition, appearance grade, post-treatment requirements, packaging, and storage/transport conditions.

FAQs​

EG uses an electrolytic deposition process, resulting in a thin, uniform coating and a smoother surface. It is better suited to applications with hohen Anforderungen an das Erscheinungsbild oder deep-drawing needs. HDG, by contrast, uses a hot-dip process that produces a thicker coating and stronger corrosion resistance, making it more suitable for outdoor oder highly corrosive environments. However, its surface is rougher, and its formability is generally less refined.

Yes. SECC is a grade defined under JIS G 3313 for electro-galvanized steel, using SPCC cold-rolled steel as the substrate.

Yes. After proper phosphating oder passivation pre-treatment, EG offers excellent coating adhesion. It is widely used for parts such as Gerätegehäuse und office equipment enclosures that require powder coating or painting.

EG has a relatively thin coating, so it is generally better suited to indoor use or only short-term outdoor exposure. For long-term outdoor service, it is usually better to use HDG or another material with stronger weather resistance, or to apply a heavy-duty protective coating system over EG.

Yes, very much so. Because the coating is thin, it has little effect on the formability of the base steel, making EG well suited to Tiefziehen und komplexes Stanzen. It is commonly used for parts such as appliance inner liners und automotive inner panels.

In spot welding, the welding current usually needs to be increased by about 25%–50%, the welding time may need to be extended, and the electrode pressure should be adjusted to reduce spatter. Since the zinc coating can contaminate the electrodes, it is recommended to use chrome copper oder composite electrodes and to strengthen cooling.

Yes. In humid conditions, EG can develop Weißrost—especially if it is not passivated or if the passivation is inadequate. Proper passivation treatment—especially chrome-free passivation—combined with good storage and transport protection can significantly reduce the risk.

If the project is indoors, requires a good surface finish and coating performance, and also needs good formability, EG is usually the best choice. If the application involves long-term outdoor exposure or a heavily corrosive environment, HDG is generally more suitable. If the budget is tight and the part will be used in a dry environment for a shorter period, CR may also be a practical option. The right choice comes from balancing environment, appearance, fabrication needs, and cost.