Only a look at the surface

Surface technology: The underestimated key technology of industrial value creation

In the public perception, surfaces are often reduced to “finish” – to appearance, colour or corrosion protection. In reality, they determine friction, wear, service life, electrical conductivity, biocompatibility or temperature resistance. They are therefore functional system components.

Especially in the mobility industry – from electric drives to fuel cells to autonomous sensor platforms – surface technology is not an add-on, but a performance enabler. Anyone who underestimates them is wasting efficiency, durability and differentiation potential.

Scientific Classification of Surface Processes

In materials science, surface processes are systematically classified – primarily according to the principle of action and depth of intervention. Among other things, the classification according to DIN 8580 (manufacturing processes) as well as thermodynamic and physicochemical mechanisms is decisive.

1. Mechanical processes

Principle: Removal or plastic deformation of the edge zone
Examples: Grinding, polishing, blasting, shot blasting
Objective: Roughness, residual compressive stresses, fatigue resistance

2. Thermochemical surface layer treatment

Principle: Diffusion of atoms into the edge zone at elevated temperature
Examples: Nitriding, case hardening, carbonitriding
Objective: Hardness, wear resistance, fatigue resistance

3. Chemical and electrochemical processes

Principle: Deposition by chemical reaction or electrolytic processes
Examples: electroplating, electroless nickel (EN), anodizing
Objective: Anti-corrosion, conductivity, decorative effects

4. Physical and plasma-assisted thin-film processes

Principle: Gas Vapor Deposition or Plasma Activation
Examples: PVD, CVD, DLC, Plasma Nitriding
Aim: Friction Reduction, Barrier Properties, High-Temperature Stability

5. Organic coatings

Principle: Polymer-based protective or functional coatings
Examples: Painting, powder coating, laminating
Objective: Corrosion, UV stability, design

6. Additive and hybrid processes

Principle: Combination of several mechanisms (e.g. laser cladding + PVD)
Goal: Function integration, repair, lightweight construction

Overview of the most important surface processes

Procedure	Category	Typical layer thickness	Improved properties	Typical Applications
Painting	Organic	20–200 μm	Korrosion, UV, Design	Body, Interior
Powder coating	Organic	60–150 μm	Mechanical robustness	Chassis components
Electroplating (Zn, Ni, Cr)	Electrochemical	5–30 μm	Corrosion, conductivity	Screws, Connectors
Chemisch Nickel (EN)	Chemical	5–50 μm	Uniformity, hardness	Precision parts
Anodizing	Electrochemical	5–25 μm	Oxidation protection, insulation	Aluminum housing
Nitriding	Thermochemisch	0.1–0.6 mm	Hardness, fatigue resistance	Gears
Case hardening	Thermochemisch	0.5–2 mm	Wear, core toughness	Transmission Components
PVD (TiN, CrN)	Physical	1–5 μm	Friction reduction	Tools, injection systems
CVD	Chemical	5–20 μm	High-temperature stability	Turbines
DLC	PVD/CVD	1–3 μm	Extremely low friction	Piston Rings
Plasma nitriding	Plasma	0.1–0.5 mm	Wear, fatigue	E-drive components
Thermal spraying	Thermal	50 μm–2 mm	Wear, insulation	Fuel cells
Laser deposition welding	Additive	>500 μm	Repair, Structure	Large components
Laminating	Organic/Hybrid	variabel	Barrier, Design	Interior, battery housing

What properties are created or improved?

Surface treatments affect:

• Tribology: Coefficient of friction (DLC <0.1 possible)
• Corrosion resistance: Zinc-nickel >1000 h salt spray
• Fatigue resistance: shot blasting induces residual compressive stresses
• Electrical conductivity: silver or copper electroplating
• Thermal Barrier: Ceramic CVD Layers
• Chemical resistance: PTFE, fluoropolymers
• Biocompatibility: Titanium Oxide Layers

The scientific basis for this is provided by tribological and materials science studies, including those published in Surface & Coatings Technology (Elsevier) and work by the Fraunhofer Institute for Surface Engineering and Thin Films IST.

Market and industry development

According to data from MarketsandMarkets, the global surface treatment market will grow to over USD 160 billion by 2030 (CAGR ~6%). The ZVO – Central Surface Technology Association reports that e-mobility, hydrogen and power electronics in particular are growth drivers.

Key projects and industrial players

Automotive & Mobility Industry

Volkswagen AG is increasingly relying on plasma-nitrided transmission components in electric drives to increase efficiency.

BMW Group uses DLC coatings in high-pressure injection systems.

Tesla, Inc. relies on highly corrosion-resistant aluminum surfaces for battery housings.

Fuel Cells & Hydrogen

Bosch is developing coated bipolar plates for fuel cells to reduce contact resistance.

thyssenkrupp nucera uses special coatings to increase the service life of electrolysis cells.

Robotics & High-Tech

KUKA AG integrates wear-resistant coatings in joint modules for longer maintenance intervals.

ABB Ltd. is focusing on corrosion-resistant surfaces in collaborative robots for the food industry.

Innovative companies in surface technology

• Oerlikon Balzers – PVD/DLC Marktführer
• Bodycote – Thermochemical processes
• Ionbond – Thin-film solutions
• Hauzer Techno Coating – PVD-Anlagen
• Plasmatreat GmbH – Atmospheric Pressure Plasma

Technological innovations

1. Functional Multilayer DLC

Improves adhesion, friction and temperature resistance.

2. Plasma activation at room temperature

Allows coating of temperature-sensitive materials.

3. Nanostructured layers

Targeted control of wettability (lotus effect).

4. Smart Coatings

Self-healing coatings, sensory coatings for condition monitoring.

Scientifically documented in papers of the Max Planck Institute for Iron Research and in Progress in Materials Science, among others.

Surface technology is not a cost factor – it is a performance multiplier

In many OEM organizations, surface technology is still assigned to purchasing or production – not to development. This is strategically wrong.

Friction reduction of a few percentage points is decisive for the range of electric drives. Corrosion resistance determines warranty and recall costs.

If you only optimize “costs per square meter” instead of looking at system performance, you will lose touch technologically.

Voices from the industry

“The service life of our components is largely determined by tribological optimization.” – Statement from technical white papers from Oerlikon Balzers.

In several publications, the Fraunhofer-Gesellschaft emphasizes that surfaces in e-mobility applications enable efficiency increases in the low single-digit percentage range – which is systemically significant.

Outlook

With increasing electrification, higher power densities and new material combinations, the importance of functionalized surfaces is growing exponentially.

The next evolutionary stage is integrated multifunctional layers that combine mechanical, electrical and sensory properties.

The mobility industry is faced with a decision:

Will surface technology continue to be regarded as a necessary production step – or as a strategic innovation lever?

Call to Action

How do you see that?

Is surface technology already strategically anchored in your organization – or is it still a “finishing topic”?

I look forward to your well-founded perspectives and experience in development, purchasing and production.