DIN 50900: Corrosion of metals – Terminology

General Definitions for Metallic Coatings

DIN 50900 is a fundamental German standard that defines the terminology, classification, and basic principles related to metallic coatings, including:

Electroplating (e.g., zinc, nickel, chromium)

Hot-dip coatings (e.g., galvanizing)

Thermal spraying

Cladding and vapor deposition

This standard provides unified definitions used across surface treatment standards, ensuring consistency in technical documentation and product specifications.

Key Content Overview

DIN 50900 is divided into several parts (originally 2 parts), and covers:

1. Definitions and General Terms

Base metal (substrate)

Coating system (single-layer or multilayer)

Adhesion, porosity, and thickness

Functional vs decorative coatings

Surface preparation (e.g., pickling, etching, blasting)

2. Classification of Coatings

According to:

Coating method (electroplated, hot-dip, vapor-deposited, etc.)

Material used (zinc, nickel, titanium, etc.)

Function (corrosion protection, wear resistance, appearance, conductivity)

3. Application Fields

Automotive, aerospace, machinery, electronics, architecture, etc.

Use Cases

DIN 50900 is often referenced when:

Specifying surface finishes in technical drawings

Preparing quality certificates for coated parts

Defining coating requirements in purchase documents

Used in conjunction with standards like DIN EN ISO 4042 (electroplated fasteners) or ISO 2063 (thermal spraying)

Related Standards

DIN EN ISO 4042-Electroplated coatings for fasteners

DIN 50930-Corrosion protection of drinking water installations

DIN 50976-Surface preparation and adhesion test

ISO 2063-Thermal spraying — Zinc, aluminum, and their alloys

ASTM B633-Electrodeposited zinc coatings

Example Applications:

Zinc-plated screws and bolts

Anodized aluminum components

Nickel-coated connectors

Hot-dip galvanized steel structures