businessIndustry Information
Aluminum Trim
Aluminum trim are long, thin and narrow extruded metal shapes that have applications in automotive design, decorative architecture, screen printing, indoor and outdoor lighting and other construction and engineering projects. Trim can either be purchased from stock offerings in a range of standard shapes and sizes, or it can be custom-ordered to fit into a unique space. Aluminum trim is valued for many of the traits of aluminum itself, a naturally occurring element and metal found in the earth’s crust. Aluminum is ductile, nonmagnetic, nonferrous, corrosion resistant and incredibly low in density. Aluminum trim is therefore weather resistant, generally impervious to both high and low temperatures, the effects of the sub, corrosion and the temptation to rust.
Aluminum trim is fabricated through the extrusion process, a process that creates objects by using a ram to force metal shapes, called billets or blanks, through a die. A die is a pre-formed, hollow profile that, in this case, creates the trim’s thin, long and narrow appearance. Extrusion can create very intricate or complex cross-sections, while putting less stress on the working material than other forming processes. Trim manufacturers may use cold extrusion, warm extrusion or hot extrusion to fabricate the trim. These extrusion methods are performed at room temperature, slightly above room temperature and at a high temperature, respectively. The advantages of cold extrusion are: closer tolerances, superior surface finishes, higher strength products and a lack of oxidation. Warm extrusion is performed above room temperature, between 800 and 1800 degrees. Warm extrusion is best for instances when a manufacturer wishes achieve a highly balanced mix of ductility, extrusion properties and any required forced. Most often, aluminum trim is fabricated using hot extrusion. Hot extrusion is performed far above room temperature, which ensures that material does not re-harden prematurely. To successfully form aluminum using the hot extrusion method, the metal must be heated above 1800 degrees.
Aluminum trim’s popularity in automotive design has grown over the past several years because it is a lighter metal, and a lighter car translates into a more energy-efficient car that uses less gas. It is also less expensive than most other metals. In fact, many, if not most, of the vehicle models created since 2012 all use aluminum trim for interior and exterior accents, instead of heavier, more expensive metals like steel and chrome. In addition to being lightweight and inexpensive, aluminum trim is flexible, can be extruded into a variety of shapes, can take on a variety of finishes, holds its shine and is highly corrosion resistant. Aluminum trim for vehicle interiors are usually fairly small, with detailed surface patterns or textures. With the help of the right finish, aluminum trim can look luxurious while saving manufacturers money and without the carrying the price of a luxury car.
In architecture, aluminum trim is used most often to create exterior accents on both residential and commercial buildings, on roofs and porches and in the form of window and door frames. To support both the decorative and structural integrity of aluminum trim used in and on buildings, aesthetic processing frequently takes place after secondary processes like powder coating. (The main purpose of powder coating is to provide water and corrosion resistance to improve an object’s lifespan and durability.) Decorative building trim also frequently undergo stamping or engraving processes, in order that they might have different raised grains. The wood grain texture seen on many home trim accents, for example, are created this way.
To get the most out of their aluminum trim, manufacturers must be aware of and strive to prevent possible extrusion defects, such as: surface cracking, internal cracking, surface lines and pipe. Surface cracking most often happens during warm or hot extrusion, when the speed, friction or temperature is too high. Surface cracking can occur during lower temperature extrusion if the extruded material gets stuck to the die long enough to fracture. Internal cracking occurs when the extrusion’s center voids or cracks. Generally, it is attributed to a state of hydrostatic tensile stress at the centerline of the die’s deformation zone. Surface lines are lines that are visible on the outside of an extruded profile. This occurs when residue from the extruded material is left behind on the die surface, producing embossed lines. To avoid this, the die must be of high quality and well-maintained. Pipe is a flow pattern that brings surface impurities and oxides to the center of a product. This is most often caused by the cooling of the outer regions of a billet or high friction.