Anodizing is a finishing technique that enhances the appearance and performance of aluminum components. It is a popular choice in many industries including automotive, aerospace, and medical because the final parts are durable and resistant to wear. However, the benefits you get from using anodized aluminum parts depend on how well and frequently you clean and maintain them.
If you want to know the appropriate way to clean specks of dirt and contaminants off anodized aluminum, then you are in the right place. This article will explain what aluminum anodizing is, how to clean anodized aluminum parts, and tips to follow to get the best results.
What is Aluminum Anodizing
Anodizing is an electrolytic passivation process that results in a thick and durable aluminum oxide layer. It involves converting the metal surface to an anodic oxide finish that serves both decorative and protective functions. Unlike other processes like painting and plating that deposit a thin layer of external material, the anodized surface is an extension of the underlying aluminum workpiece. Hence, it does not peel or chip with time.
The process of aluminum anodizing is pretty straightforward. You immerse the workpiece in an electrolytic solution which can be chromic acid or sulphuric acid. Thereafter, pass an electric current through to form the anodic oxide layer gradually. The next step is to color it with any dye of your choice. You then seal the pores of the porous oxide layer to increase resistance to corrosive substances.
Why Anodize Aluminum Parts
There are many benefits you stand to gain from anodizing aluminum metal. This process enhances many of the desirable properties of aluminum and makes it suitable for use in many applications. The following are some reasons you should anodize aluminum.
Improved corrosion resistance
Anodizing helps to improve the corrosion resistance of the aluminum part. The extra oxide layer is thick and does not break down easily when in contact with saltwater, acids, and bases. It is chemically inert which reduces the risk of contamination.
Aesthetics
Another way you would find anodized aluminum useful is the beautiful outer appearance you would get. With anodizing, you can introduce different colors such as brown, black, transparent, and gold. The aesthetics of a part is one of the first things a customer notices and it influences purchasing decisions.
Low Maintenance
An anodized aluminum part is easier to maintain and handle than the unanodized counterpart. The surface is smooth and simple to clean with basic cleaning materials. Anodized aluminum parts come with low maintenance requirements and do not build up dirt with time.
Durability
The durability of the anodized aluminum part is also top-notch. These parts can last for years even when you use them in demanding applications. It does not rust or wear out easily. This reduces the need for frequent repairs and replacement.
Step by Step Anodized Aluminum Cleaning Instructions
When using anodized aluminum parts, it is important to clean them from time to time to avoid accumulation of dirt and debris. Follow the steps below to get a clean part while preserving integrity.
Dust Removal
The first step is to remove dust and debris from the surface of the workpiece. You do this using a soft bristle brush or a dry cloth to slowly wipe loose dirt off. This step is important because debris can interfere with the cleaning process. It can also scratch the surface and give poor results.
Soap Solution Preparation
The next step is to prepare the soap solution you want to use. Select an appropriate mild and neutral soap of your choice. The pH of the soap should be between 6 and 8 to avoid unwanted reactions. Mix the soap with lukewarm water at a concentration between 1-2%. Stir thoroughly till the soap fully dissolves.
Cleaning
Using a soft cloth or sponge, apply the soap mix on the part surface carefully. Wipe the surface in straight strokes with minimum pressure. Clean all corners and crevices till there are visible changes. The cleaning time depends on the initial state of the part and the cleanliness level you want to achieve.
Tough Stain Removal
When dealing with tough stains, you may have to go for baking soda to tackle it. Mix one part of baking soda and two parts of clean water in a container. Apply the paste and make sure it covers the entire area of the stain. Allow it to sit for some minutes before wiping it off gently. If the stain persists, you may have to repeat the process and allow the water-baking soda mixture to sit for a longer time.
Disinfection
After cleaning, it is important to disinfect the surface of the anodized aluminum part to prevent contamination. You do this using a mixture of water and vinegar in a ratio of 2:1. Spray the mixture generously on the part’s surface. Leave for about 10 minutes to give the mixture time to act to kill any microorganisms. Wipe off excess solution with a clean cloth to prevent discoloration.
Rinse and Dry
The final step in anodized aluminum cleaning is to rinse and dry. Whether you have used soap, baking soda, vinegar, or a mixture of the three, you must rinse off the solution with clean water. Thereafter, dry the metal surface with a clean cloth. This helps to prevent water marks and damage as a result of moisture.
Tips and Precautions for Anodized Aluminum Cleaning
Though cleaning anodized aluminum may look easy, there are some pro tips you should know to get the best results. Consider the following when you want to clean anodized aluminum.
Use a Neutral Cleaner
Always stick with a neutral cleaner when handling anodized aluminum parts. This will protect the properties of the anodic finish. Furthermore, neutral cleaners are less likely to cause damage as a result of etching, pitting, or pH imbalance.
Clean a Test Area First
Before cleaning the workpiece surface, it is important to clean a test area first. Use the same concentration of the cleaner mixture and check for defects that were not initially present. Pre-testing ensures compatibility and detects potential damage. You can use it to identify discoloration and confirm the effectiveness of the cleaning solution.
Avoid Abrasive Materials
Do not use abrasive materials when cleaning anodized aluminum parts. These materials contain small mineral particles that can scour and scratch the surface during the cleaning process. They can damage the substrate beneath and increase the risk of corrosive atack.
Use Appropriate Soap Concentration
The concentration of the cleaning solution is also essential. Too low a soap concentration may not effectively remove all dirt and contaminants. You will need more time and effort to get the desired results. On the other hand, too high a concentration may lead to excessive foaming and discoloration which can compromise functionality.
Avoid Using Circular Motions
When applying the soap solution, do not use circular motions. Rather, clean in straight lines and move in a back-and-forth direction. Circular motions increase the risk of scratches and swirl marks. These marks are difficult to remove and can affect the aesthetics of the parts.
Use Minimal Pressure
The pressure you use also determines the quality of the final result. Avoid using too little or too much pressure when cleaning anodized aluminum components. Excessive pressure will affect the structural integrity of the part. In worst cases, you may end up removing the anodized layer during the cleaning process.
No Bleach or Acid
Bleach and acidic solutions do more harm than good when used for cleaning. They can damage the topmost oxide layer making the part susceptible to failure. Furthermore, using bleach and acid can affect the surrounding environment in cases of spillage or accidental contact.
Avoid Excess Water
Though you must use enough water to rinse off all remnants of the soap solution, avoid flooding the surface with too much water. Excess water can seep into the pores of the anodized surface and increase the risk of contamination. Additionally, the parts rust easily and you may have to replace which increases costs.
Conclusion
Aluminum anodizing is an electrochemical process that results in a durable and decorative finish. To continue to serve its function, the aluminum anodized part must be properly cleaned. Cleaning involves dusting off loose dirt before using a soap solution and a soft cloth. To prevent part damage, it is important to avoid abrasive materials and use neutral cleaners. Furthermore, clean in a straight line with minimal pressure and dry off excess water to prevent contamination.
