Important Information About Diffusion Coatings

By Marci Nielsen


the use and/or operation of metal components occurs in many different environments. The environments differ a lot and some of them cause significant effect on the metal. Effect may be caused by high temperatures or corrosive elements. Functionality, aesthetic value, and durability among other aspects get affected diversely by such adverse conditions. These effects led to research that led to the invention of diffusion coatings. These kinds of coatings are meant to offer protection to substrates against damage that results from environmental effects. This article will discuss the process and how protection is offered.

The process of applying a diffusion coating on a metal substrate is called diffusion coating too. This process is done inside a chamber at temperatures that are very high. Various metals such as nickel, iron, and cobalt are activated thermally during the procedure. Before the process can start, the substrate needs to be cleaned thoroughly first. Cleaning can be done through various methods, but abrasive blasting is commonly used. Cleaning is for removing dirt and other undesirable materials from the surface of substrates.

After being properly cleaned, the substrate is placed in a special container, which is placed inside a furnace in turn. The furnace is sometimes called a chamber. The furnace operates at very high temperatures, which range between 380-425 degrees.

At those temperatures, the diffusion of the metal occurs, which allows it to form an alloy with the substrate or component. This process lasts variable amounts of time depending on the metal used and the nature of the substrate. Typically, it lasts between two to four hours. During the entire time, the component is rotated slowly for a uniform coating to form.

When the process is finished, the coating that results is usually smooth and has a uniform thickness. The thickness can be varied depending on the purpose the components is meant to do. However, typical thicknesses are between 15 to 80 micrometers. The coating takes the color of the metal used and common ones include chromium, silicon, aluminum, and iron. Various materials can also be coated including nickel, steels, cobalt, and iron among many others.

The coating that results is capable of resisting erosion, oxidation, and reaction with substances like air and water. Metal components that are used for critical functions are made stronger, more durable, and more reliable. Gave valves, pump impellers, power generation components, and gas turbines engine constituents including vanes, blades, and cases are among the components that are coated this way.

The process is used mostly in industrial settings and few household equipment have components that are coated this way. The technology was invented several years ago and has been undergoing a lot of modifications aimed at perfecting it. Currently, there are better methods and technology for doing it.

Modern day furnaces have a lot of improvements in the form of features aimed at increasing efficiency and functionality. Today it is possible to achieve very thin coatings that are very strong and effective at eliminating corrosion. The automotive industry is particularly known for using this technology.




About the Author:



No comments: