A Practical Guide to Oxidation Processing of High-Temperature Components

The course provides a detailed explanation of the entire process involved in removing oxide layers from high-temperature machine parts, including pre-treatment, oxide layer removal, and post-treatment. It also shares practical techniques for removing oxide layers, as well as tips for surface treatment of industrial parts.

Why is it necessary to deal with the oxidation layer of high-temperature parts?

The surfaces of engine parts that work in high-temperature environments, such as pistons and turbine blades, are easily oxidized.This oxidation layer is not very conspicuous, but over time it can accelerate wear on the parts and even affect the overall performance of the equipment.We don't just do the oxidization to make it look good, the key is to make the parts more durable and reduce the losses from unexpected shutdowns.

Preparing to process.

Tools and Materials List

First, don't rush to start working. Make sure you have all the tools you will need before you begin.For example, you need to have safety gloves, a sandblasting machine (or sandpaper), chemical cleaning agents, an ultrasonic cleaning machine, and passivation solution.If possible, a magnifying glass or microscope can also be useful for checking out details.

Safety precautions.

The process of removing the oxide layer may involve the use of chemicals or high-temperature equipment. Safety is absolutely non-negotiable. Protective goggles, gas masks, and corrosion-resistant gloves are standard equipment.The working environment must also be well ventilated, especially when using acid washes.

The core step in the oxidation process.

Step 1: Cleaning and pre-treatment.

First, use industrial alcohol or a special cleaner to wipe off the oil and dirt from the surface of the components.Don't be lazy about this step, because if the surface is not thoroughly cleaned, the results of the next step will be compromised.For particularly stubborn stains, try ultrasonic cleaning, which vibrates them right off.

The oxidation layer can be removed mechanically or chemically.

Mechanical treatment: Using a sandblaster or sandpaper to rub the surface, this method is suitable when the oxidation layer is relatively thick.Take care not to grind too hard, or you'll ruin the part!

Chemical Treatment: Soak in diluted hydrochloric acid or a solution specially designed to remove oxidation.There is a little trick to this: use a small brush to gently stir the solution while it is soaking, and this will accelerate the reaction.However, don't soak them for too long. Five to 10 minutes is usually enough.

Surface treatment and protection.

After the oxide layer has been removed, the surface becomes rough, and at this point a deoxidizing liquid must be applied.After applying the passivating solution, remember to dry it off, and if you have the right conditions, apply a layer of high-temperature resistant coating. This way, if the next time you are exposed to high temperatures, the rate of oxidation will be much slower.

Avoiding common pitfalls.

What if the oxide layer is not removed completely?

If you find that there are still spots left after you've finished, chances are you didn't do the pre-treatment properly or you didn't control the timing.If the stone keeps slipping, don't force the matter. Go back a step and clean the stone again.

After treatment, the surface of the part becomes rough.

This is usually the result of over-polishing or too high a concentration of acid.He recommends that novices start with the lowest concentration of the chemical and very fine-grit sandpaper. Don't start with the "heavy artillery.

The problem of paint peeling off.

If the paint comes off easily after it has been applied, then first check to see if the surface was completely dry and whether the paint is compatible with the substrate.For example, the types of coatings used for aluminum and cast iron are very different. When you buy the material, you have to be clear about the range of applications.

Daily maintenance tips.

But even after all this, the work is not yet finished. The temperature of the parts is monitored with an infrared thermometer on a regular basis, and any abnormal rise in temperature is quickly checked out.When not in use, you can simply wipe the surface of the machine with a cloth dipped in rust inhibitor. This simple step can reduce the rate of oxidation by at least 30 %.