How to Anodize Aluminum

How to Anodize Aluminum

There are many different ways you can anodize aluminum. This article explains what anodization is, the benefits of anodizing, the materials you will need, and the steps to anodize your aluminum. Let’s get started.

What is anodization?

Anodizing is an electrochemical process that allows a thick protective finish to be applied to metal quickly and precisely.

Benefits of Anodizing Aluminum

There are many benefits to anodizing your aluminum. They include:

  • Increases water resistance
  • Increases the corrosion resistance
  • Accepts colors and dyes quite easily
  • Is environmentally friendly
  • Makes parts extremely durable
  • Is a very affordable process

Materials You Will Need

There are certain materials that you will need for this process. Some materials you may even have lying around your home right now. The materials you will need are:

  • Safety gear
  • Distilled water
  • Sulfuric acid
  • Containers (multiple)
  • Cathode
  • Aluminum or titanium wire
  • Lye
  • Acid neutralizer
  • Degreaser
  • A power source
  • Dye (if coloring your aluminum)
  • Ping pong balls

How to Anodize Aluminum in 12 Steps

Step 1. Clean Your Aluminum

First, clean your aluminum. This can be done with a microfiber towel, soap, and water.

Step 2. Put on Safety Gear

Next, put on your safety gear: gloves and protective eyewear.

Step 3. Degrease Your Aluminum

For this step, add the degreaser to your aluminum and clean it, then rinse it with distilled water.

Step 4. Etch in a Lye Bath and Rinse

You will need to etch your aluminum in a lye bath for about three to five minutes. To make a lye bath, use four tablespoons of lye for every gallon of water you use.

Step 5. Attach Your Aluminum to Your Wire

This is the part of the process where you will attach your aluminum to your wire. Keep in mind that there will be a mark where you connect the wire to your aluminum.

Step 6. Create a Mixture of Sulfuric Acid and Water

In a clean container, mix one part sulfuric acid and three parts water. Try to keep the water around 70 degrees Fahrenheit. Submerge your aluminum in the tank and keep it out of the water. Add a heater and thermometer, and then add ping pong balls to cover the surface.

Step 7. Set Up Your Power Supply and Connect to the Wire

Connect the power supply to the positive end of the wire attached to the parts. The negative side is attached to the cathode. Be aware that this is a touchy process! The amperage is now set based on the total surface area being anodized. If you want to use the dye, you will need a soft surface of around 0.02 amps per square inch.

Step 8. Anodize the Surface and Heat your Dye

You should start at 16 volts. Ensure the temperature of the tank is still 70 degrees F as the process goes on; sometimes the temperature can increase when you continue this process. During this time, you will want to heat your dye. Many colors will have a temperature of 140 degrees F, but some can work better at cooler temperatures,

Step 9. Make a Distilled Water and Neutralizer Bath

For this step, make a distilled water bath and another bath of acid neutralizer.

Step 10. Turn off the Power and Remove Your Aluminum From the Water

Remove your aluminum from the tub it is already in, and dip it into the distilled water bath from the step earlier for about 15 seconds. Then, rinse it off and place it into the acid-neutralizer bath for five minutes. Rinse it again in the distilled water.

Step 11. Add the Dye as Needed

Now you can add the dye you need to your aluminum. Simply dunk the aluminum into your dye; it should immediately begin to absorb the color. Leave the parts in there for 10-15 minutes. The longer the time, the deeper the color.

Step 12. Boil Your Aluminum

After you finish the dyeing process, boil your aluminum parts for 15 minutes, as this helps harden and seal the dye.

Visit Tampa Steel & Supply for Quality Metal and Metal Processing Services

Do you need help with metalworking and keeping your metal fresh? The experienced professionals at Tampa Steel & Supply are here to help. We provide the highest quality of services to our customers.

Request a Quote Online
 Or Call Tampa Steel & Supply at (813) 241-2801