What are the different finishes available for aluminum extrusions?

Aluminum extrusions can be finished in several ways to enhance their appearance, durability, or functionality. Common finishes include anodizing, which provides a protective oxide layer; powder coating, offering a wide range of colors and textures; painting, which can be done electrostatically or by hand; polishing, resulting in a shiny, smooth surface; brushing, which creates a satin-like finish; and chromate conversion coating, which is a pretreatment for further painting or coating. Other finishes include wood grain transfer, which gives an aluminum surface a wood-like appearance, and various types of protective films or laminates. Each finish serves different purposes, from improving aesthetics to increasing corrosion resistance.