What is Anodizing?
Type II anodizing is the most common and most widely used form of anodizing.
The process is an electrochemical method that is performed by placing aluminum in a sulfuric bath and applying a prescribed amount of DC current to achieve the oxide thickness needed. The metal becomes an “anode” hence the name anodizing. This process builds up an aluminum oxide layer on the surface that also penetrates down into the aluminum material and forms an integral part of the metal. Typically, half of the coating thickness will be surface build up and the other half will be penetration into the metal. The resulting anodized surface is then ready to be colored or sealed.
The anodizing process stops the aluminum from corroding or turning white in the weather. Anodizing insulates the aluminum from electrical currents, making it useful as a commercial anodic finish for interior applications or light exterior applications that are cleaned often or exposed to outside elements. There is a clear anodize coating, but it is also can be dyed in multiple colors available on hand or a custom color. The different series of aluminum alloys play a big role in how the part will turn out!
Type II Anodized Finishes
One of the important benefits of Type II anodizing is its ability to offer corrosion and wear protection against environmental exposures. As a thinner finish (.0002-.001"), a Class II anodic coating is suited for interior applications or light exterior applications receiving regularly scheduled cleaning and maintenance. While Class II coatings offer good hardness, they are not as durable or wear resistant as Type III hard coating. It can however improve part aesthetics by allowing the part to be dyed in various colors. This is valuable in industries where aesthetic appeal is just as important as functionality. We offer:
- Clear: a decorative finish that displays the natural finish of the substrate.
- Dyed: a vividly colored permanent finish that come in several beautiful in house & in stock colors including Black, Red, Blue, Purple, Gold, Green, Gray, Pink, Turquoise, Bronze and Orange.
Type II anodizing is an economical and affordable practice, especially when compared to the more expensive Type III anodizing.
Type III Anodized Finishes (Hard Coat)
Type III finishes provide improved wear, heat & corrosion resistance, improve surface for slide applications and they are non conductive. Hard Coat anodize thicknesses vary from 0.0005 to 0.006” (0.5-3 Mils) thick, depending on the specific aluminum alloy. In Type III anodizing half of the coating thickness penetrates into the surface of the parts while the other half builds up on the surface.
- Class 1 – undyed: The color of hard coat anodize bases on the specific alloy and the anodic thickness. Some will take on dark gray or black color while others are more bronze-gray in color. Hard anodized aluminum does not require being sealed due to its thicker surface.
- Class 2 – dyed: The most common dyed coating for hard coat anodizing is black. Depending on required thickness and alloy, the parts may look blotchy due to smaller pore size. Requires sealing to so the dye does not fade or leech out.
Although more expensive than type II, the benefits of Type III anodizing offers excellent corrosion resistance, similar to Type II, but with enhanced durability making it suitable for applications exposed to harsh environmental conditions, such as aerospace, fire arms and military components. Its superior abrasion and wear resistance ensures the longevity of parts where equipment is often exposed to extreme conditions.
Our Process
Step 1-Ultrasonic Cleaning
Step 1-Ultrasonic Cleaning
Step 1-Ultrasonic Cleaning
Generates ultrasonic waves that create millions of tiny bubbles which gently cleans any surface they come in contact with. Excellent for removing oil from the parts.
Step 2- The Cleaner
Step 1-Ultrasonic Cleaning
Step 1-Ultrasonic Cleaning
Our cleaner is a high performance, non-caustic, non-silicated, alkaline cleaner, that is very effective in the removal of soils from aluminum surfaces. When used as directed, the cleaner will not etch the part surface.
Step 3- The Etch
Step 1-Ultrasonic Cleaning
Step 4- Deoxidizer/Desmutt
After another 2 step rinse, the parts are dipped in an alkaline etch solution to remove surface oxides and metal from aluminum. The resulting surface is clean, smooth, and is ready for anodizing
Step 4- Deoxidizer/Desmutt
Step 4- Deoxidizer/Desmutt
After another 2 step rinse the parts are Rinsed in an acidic solution which removes unwanted surface alloy constituent particles not removed by the etching process.
Step 5- Anodizing
After another 2 step rinse the parts are ready to be anodized. The anodizing takes place in an electrolytic solution, which is generally dilute sulphuric acid. A current is passed between the part (anode) and electrode (cathode). This causes oxygen to gather on the surface of the part, which reacts with the base metal to form a porous oxide layer
Step 6- Nitric Acid Dip
After another 2 step rinse we dip the parts in a 5% Nitric acid solution. The Nitric acid helps to further open the pores and flush out any aluminum sulphates.
Step 7- Color Dye or Clear
After rinsing the newly formed anodic film is usually clear and very porous – it is very sensitive to absorbing color pigments. Many decorative colors, such as clear, red, blue, gold, and black can be attained by immersing the anodized parts in a dye solution.
Step 8- The Sealant
We use a high quality sealant to prevent the color from leaching out and fading over time. It also helps the anodized part from absorbing impurities, such as fingerprints
Step 9- Final Seal with Hot Water
Step 9- Final Seal with Hot Water
This is the final step in our process. This further seals the part and helps the part dry faster when taken out of the tank.
We only use deionized water on our line!
Our rinse tanks operate with a filtration system with a continuous flow of deionized water! The water is continuously cycled through filters removing impurities as we move parts through the line. With this quality control measure in place, we aspire to make the best environment for your parts, as well as our tanks!
This high quality filtration system removes color, acids & impurities from our rinse water tanks to ensure clean parts before anodizing and to prevent drag out from tank to tank. This keeps our chemical tanks working at peak performance.
Our filtration system is monitored remotely by our vendor to ensure the best water and dependable operation for the anodizing process. With this system in place we can ensure our customers we have the taken the measures to provide the best outcome and quality to meet your expectations.
Along with our bulk racks, we can also customize our racking to accommodate a variety of different sizes and shapes of parts.
Photo Gallery
Now offering Type III Hard coat anodizing!
Quick turn around times and high quality is what we strive for! Call us for more information!