Pintura de protótipos para a indústria aeroespacial

Painting prototypes for the aerospace industry

1st place

The aerospace industry is one of the most complicated industries. Its main objective is user safety. For this reason, every aspect of an aerospace product must be premium, tested and tuned to ensure maximum reliability and durability. Let's talk about planes. To receive approval, the coating process must be tested on prototype products, which is an important part of prototype manufacturing.

But is it worth painting planes? They are mainly made from aluminum alloys, which have high corrosion resistance, and you can save around $35,000 if you choose to polish the surface instead of painting it. So why do we paint our planes? Is Prototype Painting Still Necessary?

Plan the coating process for corrosion protection

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Most aircraft are made from high-strength Alclad alloy. Upon contact with oxygen, a thin oxidized protective layer forms in the first few minutes. However, this layer is quite thin and can crack or be damaged by the adverse conditions the aircraft is exposed to.

Painting helps to reinforce this thin protective layer. It is a special varnish that repels salts, adhesives, mud and liquids. However, due to temperature and voltage fluctuations, numerous small cracks appear in the coating. Corrosion can occur there.

When polishing, the quality of the surface finish is significantly improved by using fine abrasives. This greatly reduces microscopic voids and peaks in the outer alloy layer. This makes it more difficult for corrosive particles to remain on the surface. However, polishing makes the oxide layer even thinner.

To prevent corrosion, polished and painted surfaces are washed in an alkaline solution. Since most paints contain elements that repel liquids, salts and other particles, they do not need to be washed as frequently as polished surfaces. For aesthetic reasons, polished surfaces need to be cleaned twice as often as painted surfaces.

Environment

In fact, aircraft coating contains some harmful substances. One of them is chromium and the other is cadmium. Chromium is present in both the primer and the paint itself and its volatile compound. Chromium exposure causes skin and lung problems. Prolonged contact leads to cancer. Cadmium has similar toxic effects. Do you understand why it's important to pay attention to them? Manufacturers must purchase special air filters and oxidizers to prevent these elements from polluting the neighborhood.

The polish itself is harmless. However, this process uses solvents. Some of them may contain components that dilute the ozone layer. The use of such elements is harmful to the atmosphere as a whole, which is why the use of ozone diluting elements is prohibited in many countries.

Conclusion: Whether to use painting instead of polishing or vice versa depends largely on the country. Depending on whether your country has bans on the elements chromium, cadmium or ozone, you need to choose the method that is most profitable.

Marketing and Aesthetics

Marketing plays an important role in the modern aviation industry. Many airlines have an original visual style and want their aircraft to stand out. Some of them use this to draw attention to their brand. Like the guys who gave their vehicles a great Pokémon theme. But in an age when many aircraft are painted every color of the rainbow, perhaps a shiny, polished aircraft really stands out?

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Costs and maintenance

The price of well-made, painted and designed aircraft is certainly higher than that of polished aircraft. Furthermore, the painted aircraft weighs more. This means it uses more fuel. It also needs to be repainted approximately every 5 years and washed regularly.

Despite all this, maintenance costs for polished aircraft are actually higher. They may consume less fuel, but the difference is so small that it's not even worth mentioning. However, aircraft need to be re-polished approximately three times a year to maintain their shine and shine. They need to be washed more frequently and the aluminum oxide layer offers less protection against corrosion than a full 0.3mm thick layer of paint.

Finally, Boeing calculated that polished aircraft are 0.06 to 0.3% more expensive than painted ones. Therefore, in this aspect there is almost no difference in price.

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This is how aircraft painting works

Painting aerospace products is a complex and time-consuming task. First, you need to build racks that reach the roof of the plane and allow access to every corner of the plane. You will then need to remove all the small elements such as mounting pins, antennas and sensors. Then cover the windows and holes with tape to prevent drips on them. Paint is usually sprayed onto the surface with an air gun. The final stage of preparation is to wash the surfaces to remove any type of mud or grease.

First the primer is applied. It serves as a base for the following layers and guarantees better adhesion to the substrate. Next, a colored paint is sprayed and finally the varnish, which protects the paint from corrosion. Spraying generally occurs from the rear of the aircraft upwards. In total, the varnish layer is approximately 0.3 mm. If it gets thicker, the paint will crack after a few flights. Otherwise the paint will no longer be the color it should be. In order for the paint to adhere better to the surface, it is sometimes magnetized.

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Finally

To put it all together:

Coating an aircraft or spacecraft, or even just a part of it, is a complex process that requires careful testing on prototypes. At least for detecting mass changes, as they are crucial for flying machines.

In terms of price, it practically makes no difference whether you use polished or painted products.

Painted objects are better protected against corrosion than polished objects. If your product is not made of aluminum alloy, painting is essential.

Polishing and painting are harmful to the environment, so special protective equipment is required.

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