Repair of Aluminum and Titanium Aerospace Components Using the Kermetico HVAF Process to Spray Al or Ti Coatings
The repair of high-value aerospace components is essential for maximizing part lifetime, reducing operating costs, and maintaining a high level of readiness. Cold spray technologies provided a way to repair some of the most expensive parts, but there are still no practical and economical repair methods for many aerospace components made of aluminum and titanium.
Kermetico HVAF Specialized coating technology and equipment add aluminum and titanium material to worn or damaged areas with outstanding quality:
- Kermetico's HVAF Al repair coatings exhibit wrought-like microstructures with near theoretical density values.
- Kermetico HVAF Ti coatings for the aerospace overhaul are dense and well-bonded.
- The HVAF systems deposit coatings onto temperature-sensitive materials such as glass or polymers.
The Kermetico equipment will be good for general re-build of worn or corroded components that have been removed from aircraft during overhaul.
The Kermetico HVAF Process Deposits Dense Non-Oxidized Aluminum Coatings
Kermetico HVAF equipment melts Aluminum. But an oxygen depleted flame and inert gas prevent Al from oxidizing, both in the jet and on the surface, and the high-speed jet creates a high bond and low porosity coating, so the HVAF SL system deposits excellent quality Al coatings and Al layers with no nozzle clogging and no oxides in the coating structure.
HVAF Aluminum Aerospace Coating Microstucture x100
Kermetico HVAF STi System for Thermal Spraying Titanium and Alloys onto Aerospace Parts
The Properties of Ti and Titanium Alloy Coatings
Titanium is not an easy material to spray. It reacts with Oxygen and Nitrogen at relatively low temperatures. That is why most developers were trying to deposit it with a vacuum or an inert gas atmosphere. These approaches make the coating extremely expensive. Kermetico have chosen a different approach, creating an inert atmosphere inside the high velocity thermal spray gun.
A Titanium Coating has been Deposited onto the Left Substrate by Our AK7, onto the Right One – by Our STi
The particular design of this unique thermal spray system keeps Ti powder in the inert gas atmosphere all the way through the thermal spray gun until it meets the substrate and bonds there.
The Thermal Spray Restoration of Worn-out Aviation Titanium Alloy Parts
Designers use titanium alloys widely in aircraft, ships, and spacecraft due to their high tensile strength to density ratio, high corrosion resistance, fatigue resistance, high crack resistance and ability to withstand moderately high temperatures without deformation.
Many attempts have been made by different research bodies to repair titanium alloy parts with cold spray, laser cladding, and other techniques. Most of them have failed and had to resort to applying alternative materials onto the worn areas. As far as we know, the question of the MRO restoration of titanium parts is still open. With the introduction of the functional titanium STi system, we provide an instrument for high-quality repair of titanium alloy workpieces.
