Protective coating

To protect components against wear and heat or carry out dimensional adjustments, we use various coating processes. MTU Aero Solutions offers you access to these processes.

Electrolytic and chemical deposition and coating removal processes

Electrolytic and chemical deposition and coating removal processes are used to change the surface properties of an object (e.g. abrasion and wear resistance, corrosion protection, lubricity, aesthetic qualities, etc.), but may also be used to build up thickness on undersized parts or to form objects.

Process	Objective	Possible base materials
Applying and removing chrome plating	Wear- and corrosion-protection layers Dimensional adjustment layers	Al, Ti and NiCo alloys Carbon steels Cr, CrNi steels Gray cast iron
Applying and removing nickel plating (sulfamate, chemical nickel)	Dimensional adjustment layers Layers to improve solderability Corrosion-protection layers	Al, Ti, NiCo, WCu, MoCu alloys Carbon steels Cr, CrNi steels Gray cast iron Molybdenum
Deposition and removal of Tribotal 23 (Co/Cr203 dispersion layer)	Wear-protection layers with excellent vibration, friction and wear properties	Al, Ti and NiCo alloys Carbon steels Cr, CrNi steels Gray cast iron
Platinization	Hot gas corrosion protection in conjunction with calorization	Ni and Co alloys

Conversion coating processes

For different kinds of corrosion protection MTU Aero Solutions provides folllowing conversion coating processes.

Process	Objective	Possible base materials
Chromic acid anodizing (Bengough-Stuart process)	Corrosion-protection layers, holding primers for paint layers	Al alloys
Direct current anodizing	Corrosion- and wear-protection layers, holding primers for paint layers	Al alloys
Phosphating	Corrosion-protection and lubricating layers, holding primers for paint layers	Carbon steels

Diffusion coating using the CVD process

Process	Objective	Possible base materials
Calorization	Hot gas corrosion and oxidation protection	Ni and Co alloys High-alloy steels
Chromizing	Hot gas corrosion protection	Ni alloys High-alloy steels

Wet-chemical surface treatment processes

Electro polishing is an electrochemical process, used to polish, passivate, and deburr metal parts.

Process	Objective	Possible base materials
Electropolishing / Electropolish-deburring	Leveling and smoothing rough surfaces Reducing residual tensile and compressive stresses near the material surface Removing cracks near the surface and material inhomogeneities Improving fatigue behavior Opening cracks in preparation for crack test	Cr, CrNi steels Ni and Co alloys

Thermal spraying

Deposition of quality metallic and nonmetallic coating systems by means of flame spraying, atmospheric plasma spraying and highspeed oxy-fuel flame spraying.

Process	Objective	Spray materials
Atmospheric plasma spraying Flame spraying High velocity oxygen fuel spraying Cold spraying Electric arc spraying	Heat insulation layers Dimensional adjustment layers Sealing coats Layers for electrical isolation Protective layers against - Abrasion - Erosion - Hot gas corrosion	Ni alloys Co alloys Ti alloys Fe alloys MCrAlY alloys (+ CVD, fillers) AlSi alloys (+ fillers) Aluminum oxide Aluminum/Titanium oxide Zirconium oxide Chromium carbide/NiCr alloy Molybdenum Nickel/Graphite NiCrAl/Bentonite

Process

Objective

Spray materials