Anodizing of aluminum and its alloys. Scheme, description

Free technical library

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Schemes of radio-electronic and electrical devices

Anodizing of aluminum and its alloys. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Ham Radio Technologies

Comments on the article

Parts and products made of aluminum and its alloys oxidize in air, resulting in gray spots on the surface that spoil the appearance.

Duralumin (aluminum) will become more beautiful if it is anodized, as a result of which a thin passive layer is formed on the surface, preventing further oxidation.

The anodized surface has a pleasant gray color. In addition, after anodizing, the aluminum product can be easily painted in any color with conventional aniline dyes.

First, two saturated solutions are prepared separately - baking soda and table salt - in boiled water at room temperature. To obtain a saturated solution, the dissolution must be carried out for at least half an hour, periodically stirring the solution. After that, the solutions should stand for 15 minutes, and they need to be filtered.

The electrolyte is then prepared by mixing nine volume parts of baking soda solution and one volume part of salt solution (9:1).

The electrolyte is well mixed in a glass dish.

Before anodizing, the part is carefully cleaned with fine sandpaper, degreased (possibly in a hot solution of washing powder) and washed in running water, after which it should not be touched by hands. Then the part to be anodized is immersed in an electrolyte solution, which should be in an aluminum container. As a current source, you can use a regulated rectifier for a voltage of 12 V and a current of up to 2 A or a car battery.

"Plus" of the current source is attached to the part, "minus" - to an aluminum container with electrolyte. The current density should be about 15 mA/cm2. To fulfill this condition, the required current density must be multiplied by the surface area of the part in square centimeters. The current value thus calculated is maintained by adjusting the current source.

Anodizing lasts about 90 minutes - until the part is covered with a bluish-gray coating. The anodizing process can be observed by the release of air bubbles and the appearance of a slight gray coating on the surface of the anodized part.

After the end of anodizing, the part is washed in running water and cleaned with a cotton swab dipped in a solution of potassium permanganate from the products of the electrochemical reaction. After that, the surface of the part becomes smooth, with a light gray tint. The part is washed again in running water and dried in air.

If desired, the part after anodizing can be painted in a solution of aniline dye. The dye solution contains 15 g of dye and 1 ml of acetic acid per 1 liter of water.

Staining is carried out in a solution heated to 60 ... 80 ° C. The duration of exposure in the solution depends on the required color saturation and is usually 10 ... 15 minutes. To fix the color, the painted part is kept in boiling distilled water for 1 ... 1,5 minutes.

To protect the part from mechanical damage, it is useful to paint it with a colorless furniture varnish (NC).

Literature

1. Plotnikov V. Radio amateur technology.-M.: Energy, 1978. - 198 p.
2. To help the radio amateur. Issue. 108. - M.: Soviet patriot. - 80 s.

Author: V.Bashkatov, Gorlovka; Publication: N. Bolshakov, rf.atnn.ru

See other articles Section Ham Radio Technologies.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Artificial leather for touch emulation 15.04.2024

In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>

Petgugu Global cat litter 15.04.2024

Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>

The attractiveness of caring men 14.04.2024

The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>

Random news from the Archive

water bike 03.04.2009

The idea of a group of inventors from California (USA) won the international competition for new bicycle models. For residents of third world countries, where drinking water often has to be delivered from afar, the inventors offer a tricycle with a built-in tank and water filter.

On the way from the river or lake to the house, water from the tank is pumped through the filter by pedaling. Purified water accumulates in a transparent reservoir above the steering wheel. At the moment, only a prototype of the device has been made.

Other interesting news:

▪ Tellurium Mini Transistors

▪ Bats' immunity to transmissible viruses explained

▪ Artificial cartilage is superior to real

▪ Smartphone controlled by gestures

▪ gene doping

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ site section Acoustic systems. Article selection

▪ article Domostroy. Popular expression

▪ article Which snake feeds exclusively on bird eggs much larger than itself? Detailed answer

▪ article Krasnoyarsk Pillars. Nature miracle

▪ article Paints for foodstuffs. Simple recipes and tips

▪ article Radio microphone, 88...108 MHz. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews