One process a company may have to improve the substrate metal of a component is called grit blasting . This surface treatment utilizes abrasive materials (media) in particle form to achieve the desired result. This may mean
The Process
Grit blasting is not complex. In fact, it is quite simple. The major tools are:
- Blasting nozzle
- Compressed air, high pressurized liquid (usually water), pressurized gas stream (vapor)
- Abrasive media
The blasting nozzle increases the speed of the particles. They impinge on the substrate surface of the part. Their impact puts the substrate surface into compression. The result can be modifying – as in helping to reduce certain conditions for aluminum alloys such as stress corrosion cracking. It can also clean the surface e.g., removing sand, rust, paint, and scale. This helps prepare the metal for welding. Other reasons for grit blasting include roughening and improving the bonding of paint and other coatings.
Types of Grit
In grit blasting, it is possible to select from various types of grit. The many options range from alumina to emery particles, and silicon carbide to walnut shells. Each material possesses characteristics capable of producing a certain type of finish.
The decision on what material best suits the process relies on three major factors:
- Intended purpose
- Substrate – which indicates the hardness of the grit required as well its density
- Cost
By carefully matching the type of grit to the above, companies reduce the risk of not achieving the desired results.
Grit Blasting
For some, the need to improve the qualities and/or quality of the metal substrate of a component is essential. They require it to ensure the part fulfills the requirements of its application. One means of achieving this end is to put the metal component through further processes. One capable of ensuring the right finish and/or enhanced desirable characteristics such as reduced stress corrosion is grit blasting.
